TSC2005IYZLT - Texas Instruments

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FEATURES APPLICATIONS

DESCRIPTION

Pre-Processing

PINTDAV

SPI

Serial

Interface

and

Control

SCLK

SDI

RESET

SDO

VREF

X+

X-

Y+

Y-

AUX

TEMP

Mux

PENIRQ

DAV

SAR

ADC

Internal

Clock

Touch

Screen

Drivers

Interface

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

1.6V to 3.6V, 12-Bit, Nanopower, 4-WireTOUCH SCREEN CONTROLLER with SPI™ Interface

•Personal Digital Assistants23

•4-Wire Touch Screen Interface

•Cellular Phones•Ratiometric Conversion

•Portable Instruments•Single 1.6V to 3.6V Supply

•Point-of-Sale Terminals•Preprocessing to Reduce Bus Activity

•MP3 Players, Pagers•High-Speed SPI-Compatible Interface

•Multiscreen Touch Control•Internal Detection of Screen Touch•Register-Based Programmable:– 10-Bit or 12-Bit Resolution

The TSC2005 is a very low-power touch screen– Sampling Rates

controller designed to work with power-sensitive,handheld applications that are based on an advanced– System Timing

low-voltage processor. It works with a supply voltage•On-Chip Temperature Measurement

as low as 1.6V, which can be supplied by a•Touch Pressure Measurement

single-cell battery. It contains a complete,•Auto Power-Down Control

ultralow-power, 12-bit, analog-to-digital (A/D) resistivetouch screen converter, including drivers and the•Low Power:

control logic to measure touch pressure.– 800 µW at 1.8V, 50SSPS

In addition to these standard features, the TSC2005– 600 µW at 1.6V, 50SSPS

offers preprocessing of the touch screen– 75 µW at 1.6V, 8.2kSPS Eq. Rate

measurements to reduce bus loading, thus reducing•Enhanced ESD Protection:

the consumption of host processor resources that canthen be redirected to more critical functions.– ± 6kV HBM

The TSC2005 supports an SPI-compatible serial bus– ± 1kV CDM

up to 25MHz. It offers programmable resolution of 10– ± 25kV Air Gap Discharge

or 12 bits to accommodate different screen sizes and– ± 12kV Contact Discharge

performance needs.•2.5 x 3 WCSP-18 Package

The TSC2005 is available in a miniature 18-lead,U.S. Patent NO. 6246394; other patents pending.

5 x 6 array, 2.608 x 3.108 mm wafer chip-scalepackage (WCSP). The device is characterized for the– 40 °C to +85 °C industrial temperature range.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications ofTexas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2SPI is a trademark of Motorola, Inc.3All other trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright © 2006 – 2008, Texas Instruments IncorporatedProducts conform to specifications per the terms of the TexasInstruments standard warranty. Production processing does notnecessarily include testing of all parameters.

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ABSOLUTE MAXIMUM RATINGS

(1)

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled withappropriate precautions. Failure to observe proper handling and installation procedures can cause damage.

ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be moresusceptible to damage because very small parametric changes could cause the device not to meet its published specifications.

ORDERING INFORMATION

(1)

TYPICAL TYPICAL NO MISSINGINTEGRAL GAIN CODES SPECIFIED TRANSPORTLINEARITY ERROR RESOLUTION PACKAGE PACKAGE TEMPERATURE PACKAGE ORDERING MEDIA,PRODUCT (LSB) (LSB) (BITS) TYPE DESIGNATOR RANGE MARKING NUMBER QUANTITY

Small Tape18-Pin,

TSC2005IYZLT

and Reel, 2505 x 6 Matrix,TSC2005 ± 1.5 – 0.2/+4.4 11 YZL – 40 °C to +85 °C TSC2005I2.5 x 3

Tape andTSC2005IYZLRWCSP

Reel, 3000

(1) For the most current package and ordering information, see the Package Option Addendum located at the end of this data sheet, or seethe TI website at www.ti.com.

Over operating free-air temperature range (unless otherwise noted).

TSC2005 UNIT

Analog input X+, Y+, AUX to SNSGND – 0.4 to SNSVDD + 0.1 VAnalog input X – , Y – to SNSGND – 0.4 to SNSVDD + 0.1 VSNSVDD to SNSGND – 0.3 to 5 VVoltage range

SNSVDD to AGND – 0.3 to 5 VI/OVDD to DGND – 0.3 to 5 VSNSVDD to I/OVDD – 2.40 to +0.3 VDigital input voltage to DGND – 0.3 to I/OVDD + 0.3 VDigital output voltage to DGND – 0.3 to I/OVDD + 0.3 VPower dissipation WCSP package (T

Max - T

)/ θ

Low-K 113Thermal impedance, θ

WCSP package °C/WHigh-K 62Operating free-air temperature range, T

– 40 to +85 °CStorage temperature range, T

STG

– 65 to +150 °CJunction temperature, T

Max +150 °CVapor phase (60 sec) +215 °CLead temperature

Infrared (15 sec) +220 °CIEC contact discharge

(2)

X+, X – , Y+, Y – ± 12 kVIEC air discharge

(2)

X+, X – , Y+, Y – ± 25 kV

(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratingsonly, and functional operation of the device at these or any other conditions beyond those indicated is not implied. Exposure toabsolute-maximum rated conditions for extended periods may affect device reliability.(2) Test method based on IEC standard 61000-4-2. Contact Texas Instruments for test details.

Product Folder Link(s): TSC2005

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ELECTRICAL CHARACTERISTICS

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

At T

= – 40 °C to +85 °C, SNSVDD = V

REF

= +1.6V to +3.6V, I/OVDD = +1.2V to +3.6V, unless otherwise noted.

TSC2005

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

AUXILIARY ANALOG INPUT

Input voltage range 0 VREF V

Input capacitance 12 pF

Input leakage current – 1 +1 µA

A/D CONVERTER

Resolution Programmable: 10 or 12 bits 12 Bits

No missing codes 12-bit resolution 11 Bits

Integral linearity 1.5 LSB

(1)

SNSVDD = 1.6V, V

REF

= 1.6V – 0.8 to +0.3 LSBOffset error

SNSVDD = 3.0V, V

REF

= 2.5V +3.2 to +8.9 LSB

SNSVDD = 1.6V, V

REF

= 1.6V – 0.2 to 0 LSBGain error

SNSVDD = 3.0V, V

REF

= 2.5V +3.8 to +4.4 LSB

REFERENCE INPUT

REF

range 1.6 SNSVDD V

Non-continuous AUX mode, SNSVDD = 3V, V

REF

= 2.5V,VREF input current drain 5.6 µAT

= +25 °C, f

ADC

= 2MHz, f

SCLK

= 10MHz

Input impedance A/D converter not converting 1 G Ω

TOUCH SENSORS

PENIRQ 50k Ωpull-up resistor,

= +25 °C, SNSVDD = 3V, V

REF

= 2.5V 51 k ΩR

IRQ

Y+, X+ 6 ΩSwitch

on-resistance

Y – , X – 5 Ω

Switch drivers drive current

(2)

100ms duration 50 mA

TEMPERATURE MEASUREMENT

Temperature range – 40 +85 °C

Differential method

(3)

, SNSVDD = 3V V

REF

= 2.5V 1.6 °C/LSBResolution

TEMP1

(4)

, SNSVDD = 3V V

REF

= 2.5V 0.3 °C/LSB

Differential method

(3)

, SNSVDD = 3V V

REF

= 2.5V ± 2 °C/LSBAccuracy

TEMP1

(4)

, SNSVDD = 3V V

REF

= 2.5V ± 3 °C/LSB

INTERNAL OSCILLATOR

SNSVDD = 1.6V 3.6 MHzClock frequency, f

OSC

SNSVDD = 3.0V 3.8 MHz

SNSVDD = 1.6V 0.0056 %/ °CFrequency drift

SNSVDD = 3.0V 0.012 %/ °C

(1) LSB means Least Significant Bit. With V

REF

= +2.5V, one LSB is 610 µV.(2) Assured by design, but not tested. Exceeding 50mA source current may result in device degradation.(3) Difference between TEMP1 and TEMP2 measurement; no calibration necessary.(4) Temperature drift is – 2.1mV/ °C.

Product Folder Link(s): TSC2005

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TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

ELECTRICAL CHARACTERISTICS (continued)At T

= – 40 °C to +85 °C, SNSVDD = V

REF

= +1.6V to +3.6V, I/OVDD = +1.2V to +3.6V, unless otherwise noted.

TSC2005

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

DIGITAL INPUT/OUTPUT

Logic family CMOS

1.2V ≤I/OVDD < 1.6V 0.7 ×I/OVDD I/OVDD + 0.3 VV

1.6V ≤I/OVDD ≤3.6V 0.7 ×I/OVDD I/OVDD + 0.3 V

1.2V ≤I/OVDD < 1.6V – 0.3 0.2 ×I/OVDD VV

1.6V ≤I/OVDD ≤3.6V – 0.3 0.3 ×I/OVDD V

SCLK pin or CS pin – 1 1 µALogic level

10 pF

= 2 TTL loads I/OVDD – 0.2 I/OVDD V

= 2 TTL loads 0 0.2 V

LEAK

Floating output – 1 1 µA

OUT

Floating output 10 pF

Data format Straight Binary

POWER-SUPPLY REQUIREMENTS

Power-supply voltage

SNSVDD

(5)

Specified performance 1.6 3.6 V

I/OVDD

(6)

1.2 SNSVDD V

= +25 °C, filter on, M = 15,W = 7, PSM = 1, C[3:0] =(0,0,0,0), RM = 1, CL[1:0] =(0,1), BTD[2:0] = (1,0,1),

SNSVDD = I/OVDD = V

REF

= 1.6V 383 µA50SSPS, MAVEX = MAVEY =MAVEZ = 1, f

ADC

= 2MHz,f

SCLK

= 10MHz, sensor driverssupply included

= +25 °C, filter off, M = W =1, PSM = 1, C[3:0] = (0,0,0,0),RM = 1, CL[1:0] = (0,1),MAVEX = MAVEY = MAVEZ SNSVDD = I/OVDD = V

REF

= 1.6V 361 µA= 1, f

ADC

= 2MHz, f

SCLK

=10MHz, sensor drivers supplyincluded

= +25 °C, filter off, M = W =1, C[3:0] = (0,1,0,1), RM = 1,CL[1:0] = (0,1), non-cont AUX SNSVDD = I/OVDD = V

REF

= 1.6V 481 µAmode, f

ADC

= 2MHz, f

SCLK

=10MHzQuiescent supply current

(7) (8)

= +25 °C, filter off, M = W =1, C[3:0] = (0,1,0,1), RM = 1,

SNSVDD = 3V,CL[1:0] = (0,1), non-cont AUX 943 µAI/OVDD = V

REF

= 1.6Vmode, f

ADC

= 2MHz, f

SCLK

=10MHz

= +25 °C, filter on, M = 7, W= 3, C[3:0] = (0,1,0,1), RM =1, CL[1:0] = (0,1), MAVEAUX

SNSVDD = I/OVDD = V

REF

= 1.6V,= 1, non-cont AUX mode, f

ADC

522 µA~13kSPS effective rate= 2MHz, f

SCLK

= 3.5MHz, fullspeed (91kSPS equivalentrate)

= +25 °C, filter on, M = 7, W= 3, C[3:0] = (0,1,0,1), RM =1, CL[1:0] = (0,1), MAVEAUX

SNSVDD = I/OVDD = V

REF

= 1.6V,= 1, non-cont AUX mode, f

ADC

47 µA~1.17kSPS effective rate= 2MHz, f

SCLK

= 3.5MHz,reduced speed (8.2kSPSequivalent rate)

Power-down supply current T

= +25 °C, CS high, SCLK = 0, SNSVDD = I/OVDD = V

REF

= 1.6V 0.023 0.8 µA

(5) TSC2005 functions down to 1.4V, typically.(6) I/OVDD must be ≤SNSVDD.(7) Supply current from SNSVDD.(8) For detailed information on test condition parameter and bit setting, see the Digital Interface section.

Product Folder Link(s): TSC2005

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PIN CONFIGURATION

Columns

(FRONT VIEW)

ACEB D F

SNSGNDNCNC NCNCDGND

Y-

NCNC NC

I/OVDD

X-

NCNC NC

AUX

SUBGND

X+VREF Y+

SNSVDD

AGND

SCLK

PINTDAV SDO

SDI

RESET

Rows

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

YZL PACKAGE

WCSP-18(TOP VIEW, SOLDER BUMPS ON BOTTOM SIDE)

PIN ASSIGNMENTSPIN

NO. NAME I/O A/D DESCRIPTION

A1 RESET I D System reset. All register values reset to default value.

A2 DGND Digital ground

A3 I/OVDD Digital I/O interface voltage

A4 AUX I A Auxiliary channel input

A5 AGND Analog ground

B1 PINTDAV O D Interrupt output. Data available or PENIRQ depends on setting. Pin polarity with active low.

B2, B3,B4, C2,

No internal connection, but solder bumps are populated. These pins may be connected to analog ground forD2, D3, NC

mechanical stability.D4, E2,E3, E4

B5 VREF I A External reference input

C1 SDI I D Serial data input. This input is the MOSI signal for the SPI protocol.

C3, C4 NC No solder bumps for these locations.

C5 SNSVDD Power supply for sensor drivers and other analog blocks.

D1 SCLK I D Serial clock input

D5 X+ I A X+ channel input

E1 SDO O D Serial data output. This output is the MISO signal for the SPI protocol.

E5 Y+ I A Y+ channel input

F1 CS I D Chip select. This input is the slave select ( SS) signal for the SPI protocol.

F2 SNSGND Sensor driver return

F3 Y – I A Y – channel input

F4 X – I A X – channel input

F5 SUBGND Substrate ground (for ESD current)

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TIMING INFORMATION

BIT0

tDIS(CSR-SDOZ)

tH(SDI-SCLKR)

NOTE: CPOL=0,CPHA=0,Byte0cyclerequires24SCLKs,andByte1cyclerequireseightSCLKs.

tH(SCLKF-SDOVALID)

tSU(SDI-SCLKR)

tD(CSF-SDOVALID)

tSU(SCLKF-CSR)

tWH(CS)

tC(SCLK)

tSU(CSF-SCLK1R)

tFtR

tWL(SCLK)

tWH(SCLK)

BIT1

MSBIN

MSBOUT

CS SS( )

SCLK

SDO(MISO)

SDI(MOSI)

BIT0BIT1

TIMING REQUIREMENTS

(1)

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 supports SPI programming in mode CPOL = 0 and CPHA = 0. The falling edge of SCLK is used tochange output (MISO) data and the rising edge is used to latch input (MOSI) data. Eight SCLKs are required tocomplete the Byte 1 command cycle, and 24 SCLKs are required for the Byte 0 command cycle. CS can stay lowduring the entire 24 SCLKs of a Byte 0 command cycle, or multiple mixed cycles of reading and writing of bytesand register accesses, as long as the corresponding addresses are supplied.

Figure 1. Detailed I/O Timing

All specifications typical at – 40 °C to +85 °C, SNSVDD = I/OVDD = 1.6V, unless otherwise noted.

PARAMETER TEST CONDITIONS MIN MAX UNIT

WL(RESET)

(2)

Reset low time SNSVDD ≥1.6V 10 µs

SNSVDD = I/OVDD ≥1.6V and < 2.7V,

100 ns40% to 60% duty cyclet

C(SCLK)

SPI serial clock cycle time

SNSVDD = I/OVDD ≥2.7V and ≤3.6V,

40 ns40% to 60% duty cycle

SNSVDD = I/OVDD ≥1.6V and < 2.7V,

10 MHz10pF loadf

SCLK

SPI serial clock frequency

SNSVDD = I/OVDD ≥2.7V and ≤3.6V,

25 MHz10pF load

WH(SCLK)

SPI serial clock high time 0.4 ×t

C(SCLK)

0.6 ×t

C(SCLK)

WL(SCLK)

SPI serial clock low time 0.4 ×t

C(SCLK)

0.6 ×t

C(SCLK)

SU(CSF-SCLK1R)

Enable lead time 30 ns

D(CSF-SDOVALID)

Slave access time 15 ns

H(SCLKF-SDOVALID)

MISO data hold time 6 13 ns

WH(CS)

Sequential transfer delay 15 ns

SU(SDI-SCLKR)

MOSI data setup time 4 ns

H(SDI-SCLKR)

MOSI data hold time 4 ns

DIS(CSR-SDOZ)

Slave MISO disable time 15 ns

SU(SCLKF-CSR)

Enable lag time 30 ns

Rise time SNSVDD = I/OVDD = 3V, f

SCLK

= 25MHz 3 ns

Fall time SNSVDD = I/OVDD = 3V, f

SCLK

= 25MHz 3 ns

(1) All input signals are specified with t

= t

= 5ns (10% to 90% of I/OVDD) and timed from a voltage level of (V

+ V

)/2.(2) Refer to Figure 31 .

Product Folder Link(s): TSC2005

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TYPICAL CHARACTERISTICS

Temperature( C)°

SNSVDDSupplyCurrent( A)m

-40 -20

1100

1050

1000

950

900

850

800

750

0 20 40 60 80 100

I/OVDD=SNSVDD=3V

V =2.5V

REF

Temperature( C)°

I/OVDDSupplyCurrent( A)m

-40 -20

0 20 40 60 80 100

I/OVDD=SNSVDD=3V

V =2.5V

REF

-40 -20 0 20 40 60 80 100

Temperature(°C)

Power-DownSupplyCurrent(nA)

1000

800

600

400

200

SNSVDD=1.6V

SNSVDD=3.6V

SNSVDD=3.0V

SNSVDD=I/OVDD=VREF

1.2 1.6 2.0 2.4 2.8 3.2 3.6

SNSVDD(V)

Power-DownSupplyCurrent(nA)

SNSVDD=I/OVDD=VREF

T =+25 C°

SNSVDD(V)

1.6 2.0 2.4 2.8 3.2

1.50

1.25

1.00

0.75

0.50

0.25

3.6

SNSVDDSupplyCurrent(mA)

f =2MHz

ADC

f =1MHz

ADC

T =+25 C

I/OVDD=

VREF =1.6V

I/OVDD(V)

1.6 2.0 2.4 2.8 3.2

3.6

I/OVDDSupplyCurrent( A)m

f =2MHz

ADC

f =1MHz

ADC

T =+25 C

SNSVDD=3.6V

VREF =1.6V

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

At T

= – 40 °C to +85 °C, SNSVDD = V

REF

= +1.6V to +3.6V, I/OVDD = +1.2V to +3.6V, f

ADC

= f

OSC

/2, f

SCLK

= 10MHz,12-bit mode, and non-continuous AUX measurement, unless otherwise noted.

SUPPLY CURRENT SUPPLY CURRENTvs TEMPERATURE vs TEMPERATURE

Figure 2. Figure 3.

POWER-DOWN SUPPLY CURRENT POWER-DOWN SUPPLY CURRENTvs TEMPERATURE vs SNSVDD SUPPLY VOLTAGE

Figure 4. Figure 5.

SUPPLY CURRENT SUPPLY CURRENTvs SUPPLY VOLTAGE vs SUPPLY VOLTAGE

Figure 6. Figure 7.

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Temperature( C)°

-40 -20

0.6

0.4

0.2

-0.2

-0.4

-0.6

0 20 40 80 100

Deltafrom+25 C(LSB)°

I/OVDD=SNSVDD=3V

V =2.5V

REF

Temperature( C)°

Deltafrom+25 C(LSB)°

-40 -20

-2

-4

-6

0 20 40 60 80 100

I/OVDD=SNSVDD=3V

V =2.5V

REF

Temperature( C)°

-40 -20

0 20 40 60 80 100

ReferenceInputCurrent( A)m

I/OVDD=SNSVDD=3V

V =2.5V

REF

SNSVDD(V)

1.6 2.0 2.4 2.8 3.2

Y+

X+ X-

Y-

3.6

R()

X+,Y+:SNSVDDtoPin

X ,Y :PintoGND- -

Temperature( C)°

R( )W

-40 -20

0 20 40 60 80 100

X+

X-

Y+

Y-

X+,Y+:SNSVDD=3VtoPin

X ,Y :PintoGND- -

Temperature( C)°

R( )W

-40 -20

0 20 40 60 80 100

X+

X-

Y+

Y-

X+,Y+:SNSVDD=1.8VtoPin

X ,Y :PintoGND- -

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

TYPICAL CHARACTERISTICS (continued)At T

= – 40 °C to +85 °C, SNSVDD = V

REF

= +1.6V to +3.6V, I/OVDD = +1.2V to +3.6V, f

ADC

= f

OSC

/2, f

SCLK

= 10MHz,12-bit mode, and non-continuous AUX measurement, unless otherwise noted.

CHANGE IN GAIN CHANGE IN OFFSETvs TEMPERATURE vs TEMPERATURE

Figure 8. Figure 9.

REFERENCE INPUT CURRENT SWITCH ON-RESISTANCEvs TEMPERATURE vs SUPPLY VOLTAGE

Figure 10. Figure 11.

SWITCH ON-RESISTANCE SWITCH ON-RESISTANCEvs TEMPERATURE vs TEMPERATURE

Figure 12. Figure 13.

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Temperature( C)°

TEMPDiodeVoltage(mV)

-40 -20

850

800

750

700

650

600

550

500

450

400

0 20 40 60 80 100

95.2mV

138.1mV

TEMP2

TEMP1

I/OVDD=SNSVDD=3V

V =2.5V

REF

MeasurementIncludes

A/DConverterOffset

andGainErrors

SNSVDD(V)

1.6 2.0 2.4 2.8 3.2

588

586

584

582

580

578

576

574

3.6

TEMP1DiodeVoltage(mV)

T =+25 C

I/OVDD=SNSVDD

V =1.6V

REF

MeasurementIncludes

A/DConverterOffset

andGainErrors

SNSVDD(V)

1.6 2.0 2.4 2.8 3.2

704

702

700

698

696

694

692

690

3.6

TEMP2DiodeVoltage(mV)

MeasurementIncludes

A/DConverterOffset

andGainErrors

T =+25 C

I/OVDD=SNSVDD

V =1.6V

REF

SNSVDD(V)

1.6 2.0 2.4 2.8 3.2

1.2

1.0

0.8

0.6

0.4

0.2

3.6

SNSVDDSupplyCurrent(mA)

M=1,W=1

M=15,W=7

2k forX-Plane

TSC-InitiatedModeScanX,Y,Zat50SSPS

TouchSensormodeledby: W

2k forY-Plane

1k forZ(TouchResistance)

T =+25 C

I/OVDD=SNSVDD

V =1.6V

REF

t ,t ,t =DefaultValues

PVS PRE SNS

Temperature( C)°

InternalOscillatorClockFrequency(MHz)

-40 -20

3.70

3.65

3.60

3.55

3.50

0 20 40 60 80 100

SNSVDD=1.6V

Temperature( C)°

InternalOscillatorClockFrequency(MHz)

-40 -20

3.95

3.90

3.85

3.80

3.75

0 20 40 60 80 100

SNSVDD=3.0V

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

TYPICAL CHARACTERISTICS (continued)At T

= – 40 °C to +85 °C, SNSVDD = V

REF

= +1.6V to +3.6V, I/OVDD = +1.2V to +3.6V, f

ADC

= f

OSC

/2, f

SCLK

= 10MHz,12-bit mode, and non-continuous AUX measurement, unless otherwise noted.

TEMP DIODE VOLTAGE TEMP1 DIODE VOLTAGEvs TEMPERATURE vs SUPPLY VOLTAGE

Figure 14. Figure 15.

TEMP2 DIODE VOLTAGE SUPPLY CURRENTvs SUPPLY VOLTAGE vs SUPPLY VOLTAGE

Figure 16. Figure 17.

INTERNAL OSCILLATOR CLOCK FREQUENCY INTERNAL OSCILLATOR CLOCK FREQUENCYvs TEMPERATURE vs TEMPERATURE

Figure 18. Figure 19.

Product Folder Link(s): TSC2005

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OVERVIEW

X+

Y+

X-

Y-

AuxilaryInput

AGND

TSC2005

SNSGND

DGND

1 Fm

1.6VDC

0.1 Fm

Touch

Screen

GPIO

SDI

SCLK

SDO

Host

Processor

PINTDAV

RESET

SDO

SCLK

SNSVDD

VREF

I/OVDD

AUX

SNSGND

AGND

SUBGND

DGND

SDI

1 Fm0.1 Fm

( isoptional;

softwareimplementation

pollingoftheStatus

PINTDAV

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 is an analog interface circuit for a human interface touch screen device. A register-basedarchitecture eases integration with microprocessor-based systems through a standard SPI bus. All peripheralfunctions are controlled through the registers and onboard state machines. The TSC2005 features include:•Very low-power touch screen controller•Very small onboard footprint•Relieves host from tedious routine tasks by flexible preprocessing, saving resources for more critical tasks•Ability to work on very low supply voltage•Minimal connection interface allows easiest isolation and reduces the number of dedicated I/O pins required•Miniature, yet complete; requires no external supporting component. ( NOTE: Although the TSC2005 can usean external reference, it is also possible to use SNSVDD as the reference.)•Enhanced ESD protection up to 6kV

The TSC2005 consists of the following blocks (refer to the block diagram on the front page):•Touch Screen Interface•Auxiliary Input (AUX)•Temperature Sensor•Acquisition Activity Preprocessing•Internal Conversion Clock•SPI Interface

Communication with the TSC2005 is done via an SPI serial interface. The TSC2005 is an SPI slave device;therefore, data are shifted into or out of the TSC2005 under control of the host microprocessor, which alsoprovides the serial data clock.

Control of the TSC2005 and its functions is accomplished by writing to different registers in the TSC2005. Asimple serial command protocol, compatible with SPI, is used to address these registers.

The measurement result is placed in the TSC2005 registers and may be read by the host at any time. Thispreprocessing frees up the host so that resources can be redirected for more critical tasks. Two optional signalsare also available from the TSC2005 to indicate that data is available for the host to read. PINTDAV is aprogrammable interrupt/status output pin that can be programmed to indicate a pen-touch, data available, or thecombination of both. Figure 20 shows a typical application of the TSC2005.

Figure 20. Typical Circuit Configuration

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TOUCH SCREEN OPERATION

4-WIRE TOUCH SCREEN COORDINATE PAIR MEASUREMENT

ConductiveBar

InsulatingMaterial(Glass)

Silver

Ink

TransparentConductor(ITO)

BottomSide

Transparent

Conductor(ITO)

TopSide

X+

X-

Y+

Y-

ITO=IndiumTinOxide

RTOUCH +RX−plate @XPostition

4096 ǒZ2

Z1*1Ǔ

(1)

RTOUCH +RX−plate @XPostition

4096 ǒ4096

Z1*1Ǔ*RY−plate @ǒ1*YPosition

4096 Ǔ

(2)

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

A resistive touch screen operates by applying a voltage across a resistor network and measuring the change inresistance at a given point on the matrix where the screen is touched by an input (stylus, pen, or finger). Thechange in the resistance ratio marks the location on the touch screen.

The TSC2005 supports the resistive 4-wire configurations, as shown in Figure 21 . The circuit determines locationin two coordinate pair dimensions, although a third dimension can be added for measuring pressure.

A 4-wire touch screen is typically constructed as shown in Figure 21 . It consists of two transparent resistivelayers separated by insulating spacers.

Figure 21. 4-Wire Touch Screen Construction

The 4-wire touch screen panel works by applying a voltage across the vertical or horizontal resistive network.The A/D converter converts the voltage measured at the point where the panel is touched. A measurement of theY position of the pointing device is made by connecting the X+ input to a data converter chip, turning on the Y+and Y – drivers, and digitizing the voltage seen at the X+ input. The voltage measured is determined by thevoltage divider developed at the point of touch. For this measurement, the horizontal panel resistance in the X+lead does not affect the conversion because of the high input impedance of the A/D converter.

Voltage is then applied to the other axis, and the A/D converter converts the voltage representing the X positionon the screen. This process provides the X and Y coordinates to the associated processor.

Measuring touch pressure (Z) can also be done with the TSC2005. To determine pen or finger touch, thepressure of the touch must be determined. Generally, it is not necessary to have very high performance for thistest; therefore, 10-bit resolution mode is recommended (however, data sheet calculations are shown using 12-bitresolution mode). There are several different ways of performing this measurement. The TSC2005 supports twomethods. The first method requires knowing the X-plate resistance, the measurement of the X-Position, and twoadditional cross panel measurements (Z

and Z

) of the touch screen (see Figure 22 ). Equation 1 calculates thetouch resistance:

The second method requires knowing both the X-plate and Y-plate resistance, measurement of the X-Positionand the Y-Position, and Z

.Equation 2 also calculates the touch resistance:

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X-Position

MeasureX-Position

MeasureZ -Position

Touch

X+ Y+

X-Y-

Z -Position

Touch

X+ Y+

Y-X-

MeasureZ -Position

Z -Position

Touch

X+ Y+

Y-X-

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Figure 22. Pressure Measurement

When the touch panel is pressed or touched and the drivers to the panel are turned on, the voltage across thetouch panel often overshoots and then slowly settles down (decays) to a stable dc value. This effect is a result ofmechanical bouncing caused by vibration of the top layer sheet of the touch panel when the panel is pressed.This settling time must be accounted for, or else the converted value will be in error. Therefore, a delay must beintroduced between the time the driver for a particular measurement is turned on, and the time a measurement ismade.

In some applications, external capacitors may be required across the touch screen for filtering noise picked up bythe touch screen (for example, noise generated by the LCD panel or back-light circuitry). The value of thesecapacitors provides a low-pass filter to reduce the noise, but will cause an additional settling time requirementwhen the panel is touched.

The TSC2005 offers several solutions to this problem. A programmable delay time is available that sets the delaybetween turning the drivers on and making a conversion. This delay is referred to as the panel voltagestabilization time, and is used in some of the TSC2005 modes. In other modes, the TSC2005 can becommanded to turn on the drivers only without performing a conversion. Time can then be allowed before thecommand is issued to perform a conversion.

The TSC2005 touch screen interface can measure position (X,Y) and pressure (Z). Determination of thesecoordinates is possible under three different modes of the A/D converter:•TSMode1 — conversion controlled by the TSC2005 initiated by TSC;•TSMode2 — conversion controlled by the TSC2005 initiated by the host responding to the PENIRQ signal; or•TSMode3 — conversion completely controlled by the host processor.

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INTERNAL TEMPERATURE SENSOR

Converter

AGND

SNSVDD

TEMP1

TEMP2

+IN

-IN

DV+kT

q@ln(N)

(3)

T+q@DV

k@ln(N)

(4)

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

In some applications, such as battery recharging, an ambient temperature measurement is required. Thetemperature measurement technique used in the TSC2005 relies on the characteristics of a semiconductorjunction operating at a fixed current level. The forward diode voltage (V

) has a well-defined characteristicversus temperature. The ambient temperature can be predicted in applications by knowing the +25 °C value ofthe V

voltage and then monitoring the delta of that voltage as the temperature changes.

The TSC2005 offers two modes of temperature measurement. The first mode requires calibration at a knowntemperature, but only requires a single reading to predict the ambient temperature. The TEMP1 diode, shown inFigure 23 , is used during this measurement cycle. This voltage is typically 580mV at +25 °C with a 10 µA current.The absolute value of this diode voltage can vary by a few millivolts; the temperature coefficient (T

) of thisvoltage is very consistent at – 2.1mV/ °C. During the final test of the end product, the diode voltage would bestored at a known room temperature, in system memory, for calibration purposes by the user. The result is anequivalent temperature measurement resolution of 0.3 °C/LSB (1LSB = 610 µV with V

REF

= 2.5V).

Figure 23. Functional Block Diagram of Temperature Measurement Mode

The second mode does not require a test temperature calibration, but uses a two-measurement (differential)method to eliminate the need for absolute temperature calibration and for achieving 2 °C/LSB accuracy. Thismode requires a second conversion of the voltage across the TEMP2 diode with a resistance 91 times largerthan the TEMP1 diode. The voltage difference between the first (TEMP1) and second (TEMP2) conversion isrepresented by:

Where:

N = the resistance ratio = 91.k = Boltzmann's constant = 1.3807 ×10

– 23

J/K (joules/kelvins).q = the electron charge = 1.6022 ×10

– 19

C (coulombs).T = the temperature in kelvins (K).

This method can provide much improved absolute temperature measurement, but a lower resolution of1.6 °C/LSB. The resulting equation to solve for T is:

Where:

ΔV = V

(TEMP2) – V

(TEMP1) (in mV).

∴T = 2.573 ⋅ΔV (in K),

or T = 2.573 ⋅ΔV – 273 (in °C).

Temperature 1 and/or temperature 2 measurements have the same timing as Figure 39 .

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ANALOG-TO-DIGITAL CONVERTER

Converter

-REF

+REF

+IN

-IN

AUX

SNSGND

AGND

X+

X-

SNSVDD

PenTouch

RIRQ

50kW

Y+

Y-

VREF PINTDAV

Preprocessing

Zone

Detect

Control

Logic

LevelShift

Data

Available

C3-C0

MAV

SNSVDD

AGND

TEMP1

TEMP2

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Figure 24 shows the analog inputs of the TSC2005. The analog inputs (X, Y, and Z touch panel coordinates, chiptemperature and auxiliary inputs) are provided via a multiplexer to the Successive Approximation Register (SAR)Analog-to-Digital (A/D) converter. The A/D architecture is based on capacitive redistribution architecture, whichinherently includes a sample-and-hold function.

Figure 24. Simplified Diagram of the Analog Input Section

A unique configuration of low on-resistance switches allows an unselected A/D converter input channel toprovide power and an accompanying pin to provide ground for driving the touch panel. By maintaining adifferential input to the converter and a differential reference input architecture, it is possible to negate errorscaused by the driver switch on-resistances.

The A/D converter is controlled by two A/D Converter Control registers. Several modes of operation are possible,depending on the bits set in the control registers. Channel selection, scan operation, preprocessing, resolution,and conversion rate may all be programmed through these registers. These modes are outlined in the sectionsthat follow for each type of analog input. The conversion results are stored in the appropriate result register.

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Data Format

OutputCode

FS=Full-ScaleVoltage=VREF

(1)

1LSB=V /4096

REF

(1)

FS 1LSB-

11...111

11...110

11...101

00...010

00...001

00...000

1LSB

InputVoltage (V)

(2)

Reference

Variable Resolution

Conversion Clock and Conversion Time

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 output data is in Straight Binary format as shown in Figure 25 . This figure shows the ideal outputcode for the given input voltage and does not include the effects of offset, gain, or noise.

(1) Reference voltage at converter: +REF – ( – REF). See Figure 24 .(2) Input voltage at converter, after multiplexer: +IN – ( – IN). See Figure 24 .

Figure 25. Ideal Input Voltages and Output Codes

The TSC2005 uses an external voltage reference that applied to the VREF pin. It is possible to use VDD as thereference voltage because the upper reference voltage range is the same as the supply voltage range, .

The TSC2005 provides either 10-bit or 12-bit resolution for the A/D converter. Lower resolution is often practicalfor measuring slow changing signals such as touch pressure. Performing the conversions at lower resolutionreduces the amount of time it takes for the A/D converter to complete its conversion process, which also lowerspower consumption.

The TSC2005 contains an internal clock (oscillator) that drives the internal state machines that perform the manyfunctions of the part. This clock is divided down to provide a conversion clock for the A/D converter. The divisionratio for this clock is set in the A/D Converter Control register (see Table 15 ). The ability to change theconversion clock rate allows the user to choose the optimal values for resolution, speed, and power dissipation. Ifthe 4MHz (oscillator) clock is used directly as the A/D converter clock (when CL[1:0] = (0,0)), the A/D converterresolution is limited to 10-bits. Using higher resolutions at this speed does not result in more accurateconversions. 12-bit resolution requires that CL[1:0] is set to (0,1) or (1,0).

Regardless of the conversion clock speed, the internal clock runs nominally at 3.8MHz at a 3V supply (SNSVDD)and slows down to 3.6MHz at a 1.6V supply. The conversion time of the TSC2005 depends on several functions.While the conversion clock speed plays an important role in the time it takes for a conversion to complete, acertain number of internal clock cycles are needed for proper sampling of the signal. Moreover, additional times(such as the panel voltage stabilization time), can add significantly to the time it takes to perform a conversion.Conversion time can vary depending on the mode in which the TSC2005 is used. Throughout this data sheet,internal and conversion clock cycles are used to describe the amount of time that many functions take. Thesetimes must be taken into account when considering the total system design.

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Touch Detect

SNSGND

TEMP1

TEMP2

SNSVDD

PenTouch

X+

Y+

Y-

HighwhentheX+orY+

driverison,orwhenany

sensorconnection/short

circuittestsareactivated.

AGND

Sense

Viasgotosystemanaloggroundplane.

DGND

Highwhen

theX+orY+

driverison.

Control

Logic

DataAvailable

Level

Shifter

50k

IRQ

SNSVDD

PINTDAV

AnalogVDD

Plane

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

PINTDAV can be programmed to generate an interrupt to the host. Figure 26 details an example for theY-position measurement. While in the power-down mode, the Y – driver is on and connected to GND. The internalpen-touch signal depends on whether or not the X+ input is driven low. When the panel is touched, the X+ inputis pulled to ground through the touch screen and the internal pen-touch output is set to low because of thedetection on the current path through the panel to GND, which initiates an interrupt to the processor. During themeasurement cycles for X- and Y-Position, the X+ input is disconnected, which eliminates any leakage currentfrom the pull-up resistor to flow through the touch screen, thus causing no errors.

Figure 26. Example of a Pen-Touch Induced Interrupt via the PINTDAV Pin

In modes where the TSC2005 must detect whether or not the screen is still being touched (for example, whendoing a pen-touch initiated X, Y, and Z conversion), the TSC2005 must reset the drivers so that the R

IRQ

resistoris connected again. Because of the high value of this pull-up resistor, any capacitance on the touch screen inputswill cause a long delay time, and may prevent the detection from occurring correctly. To prevent this possibledelay, the TSC2005 has a circuit that allows any screen capacitance to be precharged, so that the pull-upresistor does not have to be the only source for the charging current. The time allowed for this precharge, as wellas the time needed to sense if the screen is still touched, can be set in the configuration register.

This configuration underscores the need to use the minimum possible capacitor values on the touch screeninputs. These capacitors may be needed to reduce noise, but too large a value will increase the neededprecharge and sense times, as well as the panel voltage stabilization time.

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Preprocessing

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 offers an array of powerful preprocessing operations that reduce unnecessary traffic on the busand reduce host processor loading. This reduction is especially critical for the serial interface, where limitedbandwidth is a tradeoff, keeping the connection lines to a minimum.

All data acquisition tasks are looking for specific data that meet certain criteria. Many of these tasks fall into apredefined range, while other tasks may be looking for a value in a noisy environment. If these data are all to beretrieved by host processor for processing, the limited bus bandwidth will be quickly saturated, along with thehost processor processing capability. In any case, the host processor must always be reserved for more criticaltasks, not for routine work.

The preprocessing unit consists of two main functions: the combined MAV filter (median value filter andaveraging filter), followed by the zone detection.

Preprocessing - Median Value Filter and Averaging Value Filter

The first preprocessing function, a combined MAV filter, can be operated independently as a median value filter(MVF), an averaging value filter (AVF) and a combined filter (MAVF).

If the acquired signal source is noisy because of the digital switching circuit, it may be necessary to evaluate thedata without noise. In this case, the median value filter (MVF) operation helps to discard the noise. The array ofNconverted results is first sorted. The return value is either the middle (median value) of an array of Mconvertedresults, or the average value of a window size of Wof converted results:•N = the total number of converted results used by the MAV filter•M = the median value filter size programmed•W = the averaging window size programmed

If M = 1, then N = W. A special case is W = 1, which means the MAVF is bypassed. Otherwise, if W > 1, onlyaveraging is performed on these converted results. In either case, the return value is the averaged value ofwindow size W of converted results. If M > 1 and W = 1, then N = M, meaning only the median value filter isoperating. The return value is the middle position converted result from the array of M converted results. If M > 1and W > 1, then N = M. In this case, W < M. The return value is the averaged value of middle portion W ofconverted results out of the array of M converted results. Since the value of W is an odd number in this case, theaveraging value is calculated with the middle position converted result counted twice (so a total of W + 1converted results are averaged).

Table 1. Median Value Filter Size Selection

MEDIAN VALUE FILTER POSSIBLE AVERAGING WINDOW SIZEM1 M0 M = W =

0 0 1 1, 4, 8, 160 1 3 11 0 7 1, 31 1 15 1, 3, 7

Table 2. Averaging Value Filter Size Selection

AVERAGING VALUE FILTER SIZE SELECTIONW =

W1 W0 M = 1 (Averaging Only) M > 1

0 0 1 10 1 4 31 0 8 71 1 16 Reserved

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NAcquired

Data

Nm asue rementsinput

intotemporaryarray

Sortby

descendingorder

Averagingoutp tu

fromwindowW

M=1

M>1andW=1 M

NMedian value

fromarrayM

M>1andW>1

Averagingoutp tu

fromwindowW

Zone Detection

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

NOTE: The default setting for MAVF is MVF (median value filter with averaging bypassed) for any invalidconfiguration. For example, if (M1, M0, W1, W0) = (1,0,1,0), the MAVF performs as it was configured for(1,0,0,0), median filter only with filter size = 7 and no averaging. The only exception is M > 1 and (W1, W0) =(1,1). This setting is reserved and should not be used.

Table 3. Combined MAV Filter Setting

M W INTERPRETATION N = OUTPUT

= 1 = 1 Bypass both MAF and AVF W The converted result= 1 > 1 Bypass MVF only W Average of W converted results> 1 = 1 Bypass AVF only M Median of M converted resultsAverage of middle W of M converted results with the median> 1 > 1 M > W M

counted twice

The MAV filter is available for all analog inputs including the touch screen inputs, temperature measurementsTEMP1 and TEMP2, and the AUX measurement.

Figure 27. MAV Filter Operation (patent pending)

The Zone Detection unit is capable of screening all processed data from the MAVF and retaining only the data ofinterest (data that fit the prerequisite). This unit can be programmed to send an alert if a predefined condition setby two threshold value registers is met. Three different zones may be set:1. Above the upper limit (X ≥Threshold High)2. Between the two thresholds (Threshold Low < X < Threshold High)3. Below the lower limit (X ≤Threshold Low)

The AUX and temperatures TEMP1 and TEMP2 have separate threshold value registers that can be enabled ordisabled. This function is not available to the touch screen inputs. Once the preset condition is met, the DAVoutput to the PINTDAV pin is pulled low and the corresponding DAV bit is set.

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DIGITAL INTERFACE

CONTROL BYTE

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 communicates through a standard SPI bus. The SPI allows full-duplex, synchronous, serialcommunication between a host processor (the master) and peripheral devices (slaves). The SPI mastergenerates the synchronizing clock and initiates transmissions. The SPI slave devices depend on a master to startand synchronize transmissions.

A transmission begins when initiated by a master SPI. The byte from the master SPI begins shifting in on theslave SDI (MOSI — master out, slave in) pin under the control of the master serial clock. As the byte shifts in onthe SDI (MOSI) pin, a byte shifts out on the SDO (MISO — master in, slave out) pin to the master shift register.

The idle state of the TSC2005 serial clock is logic low, which corresponds to a clock polarity setting of 0 (typicalmicroprocessor SPI control bit CPOL = 0). The TSC2005 interface is designed so that with a clock phase bitsetting of 0 (typical microprocessor SPI control bit CPHA = 0), the master begins driving its MOSI pin and theslave begins driving its MISO pin half an SCLK before the first serial clock edge. The CS ( SS, slave select) pincan remain low between transmissions.

Table 4. Standard SPI Signal Names vs Common Serial Interface Signal Names

SPI SIGNAL NAMES COMMON SERIAL INTERFACE NAMES

SS (Slave Select) CS (Chip Select)MISO (Master In Slave Out) SDO (Serial Data Out)MOSI (Master Out Slave In) SDI (Serial Data In)

Table 5. Control Byte Format:Start a Conversion and Mode Setting

MSB LSBD7 D6 D5 D4 D3 D2 D1 D0

C3 C2 C1 C0 RM SWRST STS(Control Byte 1)

0ReservedA3 A2 A1 A0 PND0 R/ W(Control Byte 0) (Write '0')

Table 6. Control Byte 1 Bit Register Description (D7 = 1)

BIT NAME DESCRIPTION

D7 Control Byte ID 1D6-D3 C3-C0 Converter Function Select as detailed in Table 70: 10 BitD2 RM

1: 12 BitSoftware ResetD1 SWRST

1: Reset all register values to defaultD0 STS Stop bit for all converter functions

Bit D7: Control Byte ID

1: Control Byte 1 (start conversion and channel select and conversion-related configuration).

0: Control Byte 0 (read/write data registers and non-conversion-related controls).

Bits D6-D3: C3-C0

Converter function select bits. These bits select the input to be converted, and the converter function to beexecuted. Table 7 lists the possible converter functions.

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Touch Screen Scan Function for XYZ or XY

Touch Screen Sensor Connection Tests for X-Axis and Y-Axis

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Table 7. Converter Function Select

C3 C2 C1 C0 FUNCTION

Touch screen scan function: X, Y, Z

, and Z

coordinates converted and the results returned0 0 0 0 to X, Y, Z

, and Z

data registers. Scan continues until either the pen is lifted or a stop bit issent.

Touch screen scan function: X and Y coordinates converted and the results returned to X and0001

Y data registers. Scan continues until either the pen is lifted or a stop bit is sent.Touch screen scan function: X coordinate converted and the results returned to X data0010

Touch screen scan function: Y coordinate converted and the results returned to Y data0011

Touch screen scan function: Z

and Z

coordinates converted and the results returned to Z

10100

and Z

data registers.0 1 0 1 Auxiliary input converted and the results returned to the AUX data register.A temperature measurement is made and the results returned to the Temperature0110

Measurement 1 data register.A differential temperature measurement is made and the results returned to the Temperature0111

Measurement 2 data register.1 0 0 0 Auxiliary input is converted continuously and the results returned to the AUX data register.Touch screen panel connection to X-axis drivers is tested. The test result is output to1001

PINTDAV and shown in STATUS register.Touch screen panel connection to Y-axis drivers is tested. The test result is output to1010

PINTDAV and shown in STATUS register.Touch screen panel short-circuit (between X and Y plates) is tested through X-axis. The test1011

result is output to PINTDAV and shown in the STATUS register.RESERVED (Note: any condition caused by this command can be cleared by setting the STS1100

bit to 1).1 1 0 1 Turn on X+, X – drivers1 1 1 0 Turn on Y+, Y – drivers1 1 1 1 Turn on Y+, X – drivers

C3-C0 = 0000 or 0001: These scan functions can collaborate with the PSM bit that defines the control mode ofconverter functions. If the PSM bit is set to '1', these scan function select commands are recommended to beissued before a pen touch is detected in order to allow the TSC2005 to initiate and control the scan processesimmediately after the screen is touched. If these functions are not issued before a pen touch is detected, theTSC2005 waits for the host to write these functions before starting a scan process. If PSM stays as '1' after aTSC-initiated scan function is complete, the host is not required to write these function select bits again for eachof the following pen touches after the detected touch. In the host-controlled converter function mode (PSM = 0),the host must send these functions select bits repeatedly for each scan function after a detected pen touch.

Range of resistances of different touch screen panels can be selected by setting the TBM bits in CFR1; seeTable 20 . Once the resistance of the sensor panel is selected, two continuity tests are run separately for theX-axis and Y-axis. The unit under test must pass both connection tests to ensure that a proper connection issecured.

C3-C0 = 1001: PINTDAV = 0 during this connection test. A '1' shown at end of the test indicates the X-axisdrivers are well-connected to the sensor; otherwise, X-axis drivers are poorly connected. If drivers fail to connect,then PINTDAV stays low until a stop bit (STS set to '1') is issued.

C3-C0 = 1010: PINTDAV = 0 during this connection test. A '1' shown at end of the test indicates the Y-axisdrivers are well-connected to the sensor; otherwise, Y-axis drivers are poorly connected. If the drivers are fail toconnect, then PINTDAV stays low until a stop bit (STS set to '1') is issued.

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Touch Sensor Short-Circuit Test

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

If the TBM bits of CFR1 detailed in Table 20 are all set to '1', a short-circuit in the touch sensor can be detected.

C3-C0 = 1011: PINTDAV = 0 during this short-circuit test. A '1' shown at end of the test indicates there is noshort-circuit detected (through X-axis) between the flex and stable layers. If there is a short-circuit detected,PINTDAV stays low until a stop bit (STS set to '1') is issued.

C3-C0 = 1100: Reserved.

RM— Resolution select. If RM = 1, the conversion result resolution is 12-bit; otherwise, the resolution is 10-bit.This bit is the same RM bit shown in CFR0.

SWRST— Software reset input. All register values are set to default value if a '1' is written to this bit. This bit mustbe set to '0' in Control Byte 1 in order to cancel the software reset and resume normal operation.

STS— Stop bit for all converter functions. When writing a '1' to this register, this bit aborts the converter functioncurrently running in the TSC2005. A '0' must be written to this register in order to end the stop bit. This bit canonly stop converter functions; it does not reset any data, status, or configuration registers. This bit is the sameSTS bit shown in CFR0, but can only be read through the CFR0 register with different interpretations.

Table 8. STS Bit Operation

OPERATION VALUE DESCRIPTION

Write 0 Normal operationWrite 1 Stop converter functions and power down

Table 9. Control Byte 0 Bit Register Description (D7 = 0)

BIT NAME DESCRIPTION

1: Control Byte 1 — start conversion, channel select, and converison-related configurationD7 Control Byte ID

0: Control Byte 0 — read/write data registers and non-conversion-related controlsD6-D3 A3-A0 Register Address Bits as detailed in Table 10D2 RESERVED A '0' must be set in this bit for normal operationPower Not Down Control1: A/D converter biasing circuitry is always on between conversions, but is shut down after the converterD1 PND0 function stops0: A/D converter biasing circuitry is shut down either between conversions or after the converter functionstopsTSC Internal Register Data Flow ControlD0 R/ W 1: Read from TSC internal registers0: Write to TSC internal registers

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START A CONVERTER FUNCTION (CONTROL BYTE 1)

ControlByte1Write

( )SS

SCLK

SDI

(MOSI)

D7 D3D5 D4 D2

D6 D0D1

MSB LSB

65432 87

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Table 10. Internal Register Map

A3 A2 A1 A0 REGISTER CONTENT READ/WRITE

0 0 0 0 X measurement result R0 0 0 1 Y measurement result R0 0 1 0 Z

measurement result R0 0 1 1 Z

measurement result R0 1 0 0 AUX measurement result R0 1 0 1 Temp1 measurement result R0 1 1 0 Temp2 measurement result R0 1 1 1 Status R1 0 0 0 AUX high threshold R/W1 0 0 1 AUX low threshold R/W1 0 1 0 Temp high threshold (apply to both TEMP1 and TEMP2) R/W1 0 1 1 Temp low threshold (apply to both TEMP1 and TEMP2) R/W1 1 0 0 CFR0 R/W1 1 0 1 CFR1 R/W1 1 1 0 CFR2 R/W1 1 1 1 Converter function select status R

R/ W— Register read and write control. A '1' indicates the contents of the internal register addressed by A3-A0 aresent to SDO at the next SPI interface clock cycle. A '0' indicates the data following Control Byte 0 on SDI arewritten into registers addressed by A3-A0.

Control Byte 1 must begin with D7 = 1, as shown in Figure 28 . Control Byte 1 starts the converter function that ischosen by C3-C0, as shown in Table 7 . After sending Control Byte 1, the master does not need to hold CS low,and can release CS for operating other slave devices that share the same SCLK. After the converter functioncompletes or stops, the preprocessed data or data set are stored in data registers and can be read by sendingControl Byte 0 with Read Bit and a proper address in A3-A0. For the detailed operating procedures, see theOperation section.

Figure 28. Interface Timing — Control Byte 1

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ReadRegisterViaControlByte0

SCLK

SDI

(MOSI)

SDO

(MISO)

MSB

MSB LSB

Hi-Z Hi-Z

L BS

0 A3 A2 A1 A0 1 0

D15 D14 D13 D9 D8 D4 D0

D6 D5 D4 D3 D2 D1 D0

654321 1 387 2 161587

( )SS

WritetoRegisterViaControlByte0

SCLK

SDI

(MOSI)

SDO

(MISO)

MSB LSB

Hi-Z

0 A3 A2 A1 A0 0

D6 D5 D4 D3 D2 D1 D0

654321 1 387 2 161587

( )SS

MSB L BS

D15 D14 D13 D9 D8 D4 D0D5 D1

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Control byte 0, beginning with D7 = 0, is used to access the internal registers. This control byte uses the last bit,D0, to control the flow of data. If D0 is '1', then the content of the register pointed by the address bits (A3-A0) isoutput to SDO (MISO) in the next cycle. Otherwise, the data coming from SDI (MOSI) are written to the registerproperly pointed to by the address bits in the control byte (if the write mode is available for the pointed register).After Control Byte 0 with Read/Write Bit followed by a 16-bit word on SDO/SDI completes, the master can holdCS low to send another Control Byte 0 with Read/Write Bit followed by a 16-bit word on SDO/SDI as many timesas the master is able to operate.

Figure 29. Interface Timing — Sending Control Byte 0 with Read Bit

Figure 30. Interface Timing — Sending Control Byte 0 with Write Bit

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COMMUNICATION PROTOCOL

Configuration Register 0

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 is controlled entirely by registers. Reading and writing to these registers are accomplished by theuse of Control Byte 0, which includes a 4-bit address plus one read/write TSC register control bit. The dataregisters defined in Table 10 are all 16-bit, right-adjusted. NOTE: Except for some configuration registers and theStatus register that are full 16-bit registers, the value registers are 12-bit (or 10-bit) data preceded by four (or six)zeros.

Table 11. Configuration Register 0 (Reset Value = 4000h for Read; 0000h for Write)MSB LSBD15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

PSM STS RM CL1 CL0 PV2 PV1 PV0 PR2 PR1 PR0 SN2 SN1 SN0 DTW LSM

PSM— Pen status/control mode. Reading this bit allows the host to determine if the screen is touched. Writing tothis bit selects the mode used to control the flow of converter functions that are either initiated and/or controlledby host or under control of the TSC2005 responding to a pen touch. When reading, the PSM bit indicates if thepen is down or not. When writing to this register, this bit determines if the TSC2005 controls the converterfunctions, or if the converter functions are host-controlled. The default state is the host-controlled converterfunction mode (0). The other state (1) is the TSC-initiated scan function mode that must only collaborate withC3-C0 = 0000 or 0001 in order to allow the TSC2005 to initiate and control the scan function for XYZ or XY whena pen touch is detected.

Table 12. PSM Bit Operation

OPERATION VALUE DESCRIPTION

Read 0 No screen touch detectedRead 1 Screen touch detectedWrite 0 Converter functions initiated and/or controlled by hostWrite 1 Converter functions initiated and controlled by the TSC2005

STS— A/D converter status. When reading, this bit indicates if the converter is busy or not busy. Continuousscans or conversions can be stopped by writing a '1' to this bit, immediately aborting the running converterfunction (even if the pen is still down) and causing the A/D converter to power down. The default state for write is0 (normal operation), and the default state for read is 1 (converter is not busy). NOTE: The same bit can bewritten through Control Byte 1.

Table 13. STS Bit Operation

OPERATION VALUE DESCRIPTION

Read 0 Converter is busyRead 1 Converter is not busyWrite 0 Normal operationWrite 1 Stop converter function and power down

RM— Resolution control. The A/D converter resolution is specified with this bit. See Table 14 for a description ofthese bits. This bit is the same whether reading or writing, and defaults to 0. Note that the same bit can bewritten through Control Byte 1.

Table 14. A/D Converter Resolution Control

RM FUNCTION

0 10-bit resolution. Power-up and reset default.1 12-bit resolution

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CL1, CL0— Conversion clock control. These two bits specify the clock rate that the A/D converter uses toperform conversion, as shown in Table 15 . These bits are the same whether reading or writing.

Table 15. A/D Converter Conversion Clock Control

CL1 CL0 FUNCTION

0 0 f

ADC

= f

OSC

/1. This is referred to as the 4MHz A/D converter clock rate, 10-bit resolution only.0 1 f

ADC

= f

OSC

/2. This is referred to as the 2MHz A/D converter clock rate.1 0 f

ADC

= f

OSC

/4. This is referred to as the 1MHz A/D converter clock rate.1 1 Reserved

PV2-PV0— Panel voltage stabilization time control. These bits specify a delay time from the moment the touchscreen drivers are enabled to the time the voltage is sampled and a conversion is started. These bits allow theuser to adjust the appropriate settling time for the touch panel and external capacitances. See Table 16 forsettings of these bits. The default state is 000, indicating a 0 µs stabilization time. These bits are the samewhether reading or writing.

Table 16. Panel Voltage Stabilization Time Control

PV2 PV1 PV0 STABILIZATION TIME (t

PVS

)

0 0 0 0 µs0 0 1 100 µs0 1 0 500 µs0 1 1 1ms1 0 0 5ms1 0 1 10ms1 1 0 50ms1 1 1 100ms

PR2-PR0— Precharge time selection. These bits set the amount of time allowed for precharging any pincapacitance on the touch screen prior to sensing if a pen touch is happening.

Table 17. Precharge Time Selection

PR2 PR1 PR0 PRECHARGE TIME(t

PRE

)

0 0 0 20 µs0 0 1 84 µs0 1 0 276 µs0 1 1 340 µs1 0 0 1.044ms1 0 1 1.108ms1 1 0 1.300ms1 1 1 1.364ms

SNS2-SNS0— Sense time selection. These bits set the amount of time the TSC2005 waits to sense whether thescreen is touched after converting a coordinate.

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Configuration Register 1

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Table 18. Sense Time Selection

SNS2 SNS1 SNS0 SENSE TIME (t

SNS

)

0 0 0 32 µs0 0 1 96 µs0 1 0 544 µs0 1 1 608 µs1 0 0 2.080ms1 0 1 2.144ms1 1 0 2.592ms1 1 1 2.656ms

DTW— Detection of pen touch in wait (patent pending). Writing a '1' to this bit enables the pen touch detection inbackground while waiting for the host to issue the converter function in host-initiated/controlled modes. Thisdetection in background allows the TSC2005 to pull high at PINTDAV to indicate no pen touch detected whilewaiting for the host to issue the converter function. If the host polls a high state at PINTDAV before the convertfunction is sent, the host can abort the issuance of the convert function and stay in the polling PINTDAV modeuntil the next pen touch is detected.

LSM— Longer sampling mode. When this bit is set to '1', the extra 500ns of sampling time is added to the normalsampling cycles of each conversion. This additional time is represented as approximately two internal oscillatorclock cycles.

Configuration register 1 (CFR1) defines the connection test-bit modes configuration and the batch delayselection.

Table 19. Configuration Register 1 (Reset Value = 0000h)MSB LSBD15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

Resrvd Resrvd Resrvd Resrvd TBM3 TBM2 TBM1 TBM0 Resrvd Resrvd Resrvd Resrvd Resrvd BTD2 BTD1 BTD0

TBM3-TBM0— Connection test-bit modes (patent pending). These bits specify the mode of test bits used for thepredefined range of the combined X-axis and Y-axis touch screen panel resistance (R

Table 20. Touch Screen Resistance Range and Test-Bit Modes

TEST-BIT MODES

TSTBM3 TBM2 TBM1 TBM0 (k Ω)

0 0 0 0 0.170 0 0 1 0.17 < R

≤0.520 0 1 0 0.52 < R

≤0.860 0 1 1 0.86 < R

≤1.60 1 0 0 1.6 < R

≤2.20 1 0 1 2.2 < R

≤3.60 1 1 0 3.6 < R

≤5.00 1 1 1 5.0 < R

≤7.81 0 0 0 7.8 < R

≤10.51 0 0 1 10.5 < R

≤16.01 0 1 0 16.0 < R

≤21.61 0 1 1 21.6 < R

≤32.61 1 0 0 Reserved1 1 0 1 Reserved1 1 1 0 Reserved1 1 1 1 Only for short-circuit panel test

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BTD2-BTD0— Batch Time Delay mode. These are the selection bits that specify the delay before asample/conversion scan cycle is triggered. When it is set, Batch Time Delay mode uses a set of timers toautomatically trigger a sequence of sample-and-conversion events. The mode works for both TSC-initiated scans(XYZ or XY) and host-initiated scans (XYZ or XY).

A TSC-initiated scan (XYZ or XY) can be configured by setting the PSM bit in CFR0 to '1' and C[3:0] in ControlByte 1 to '0000' or '0001'. In the case of a TSC-initiated scan (XYZ or XY), the sequence begins with the TSCresponding to a pen touch. After the first processed sample set completes during the batch delay, the scanenters a wait mode until the end of the batch delay is reached. If a pen touch is still detected at that moment, thescan continues to process the next sample set, and the batch delay is resumed. The throughput of the processedsample sets (shown in Table 21 as sample sets per second, or SSPS) is regulated by the selected batch delayduring the time of the detected pen touch. A TSC-initiated scan (XYZ or XY) can be configured by setting thePSM bit in CFR0 to '1' and C[3:0] in Control Byte 1 to '0000' or '0001'. Note that the throughput of the processedsample set also depends on the settings of stabilization, precharge, and sense times, and the total number ofsamples to be processed per coordinates. If the accrual time of these factors exceeds the batch delay time, theaccrual time dominates. Batch delay time starts when the pen touch initiates the scan function that convertscoordinates.

A host-initiated scan (XYZ or XY) can be configured by setting the PSM bit in CFR0 to '0' and C[3:0] in ControlByte 1 to '0000' or '0001'. For the host-initiated scan (XYZ or XY), the host must set TSC internal register C[3:0]in Control Byte 1 to '0000' or '0001' initially after a pen touch is detected; see Conversion Controlled by TSC2005Initiated by Host (TSMode 2) , in the Theory of Operation section. After the scan (XYZ or XY) is engaged, thethroughput of the processed sample sets is regulated by the selected batch delay timer, as long as the initialdetected touch is not interrupted.

Table 21. Touch Screen Throughput and Batch Selection Bits

BATCH DELAY SELECTION THROUGHPUT FOR TSC-INITIATEDDELAY TIME OR HOST-INITIATED SCAN, XYZ OR XYBTD2 BTD1 BTD0 (ms) (SSPS)

0 0 0 0 Normal operation throughput depends on settings.0 0 1 1 10000 1 0 2 5000 1 1 4 2501 0 0 10 1001 0 1 20 501 1 0 40 251 1 1 100 10

For example, if stabilization time, precharge time, and sense time are selected as 100 µs, 84 µs, and 96 µs,respectively, and the batch delay time is 2ms, then the scan function enters wait mode after the first processedsample set until the 2ms of batch delay time is reached. When the scan function starts to process the secondsample set (if the screen is still touched), the batch delay restarts at 2ms (in this example). This procedureremains regulated by 2ms until the pen touch is not detected or the scan function is stopped by a stop bit or anyreset form.

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Configuration Register 2

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Configuration register 2 (CFR2) defines the preprocessor configuration.

Table 22. Configuration Register 2 (Reset Value = 0000h)MSB LSBD15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

MAVE MAVE MAVE MAVE MAVEPINTS1 PINTS0 M1 M0 W1 W0 TZ1 TZ0 AZ1 AZ0 Resrvd

X Y Z AUX TEMP

PINTS1 (default 0) — This bit controls the output format of the PINTDAV pin. When this bit is set to '0', the outputformat is shown as the AND-form of internal signals of PENIRQ and DAV). When this bit is set to '1', PINTDAVoutputs PENIRQ only.

PINTS0 (default 0) — This bit selects what is output on the PINTDAV pin. If this bit set to '0', the output format ofPINTDAV depends on the selection made on the PINTS1 bit. If this bit set to '1', the internal signal of DAV isoutput on PINTDAV.

Table 23. PINTSx Selection

PINTS1 PINTS0 PINTDAV PIN OUTPUT =

0 0 An AND combination of PENIRQ (active low) and DAV (active high).0 1 Data available, DAV (active low).1 0 An interrupt, PENIRQ (active low) generated by pen-touch.1 1 Data available, DAV (active low).

M1, M0, W1, W0 (default 0000) — Preprocessing MAV filter control. Note that when the MAV filter is processingdata, the STS bit and the corresponding DAV bits in the status register indicate that the converter is busy until allconversions necessary for the preprocessing are complete. The default state for these bits is 0000, whichbypasses the preprocessor. These bits are the same whether reading or writing.

TZ1 and TZ0, or AZ1 and AZ0 (default 00) — Zone detection bit definition (for TEMP or AUX measurements).TZ1 and TZ0 are for the TEMP measurement. AZ1 and AZ0 are for the AUX measurement. The action taken inzone detection is to store the processed data in the corresponding data registers and to update thecorresponding DAV bits in status register. If the processed data do not meet the selected criteria, these data areignored and the corresponding DAV bits are not updated. When zone detection is disabled, the processed dataare simply stored in the corresponding data registers and the corresponding DAV bits are updated without anycomparison of criteria. Note that the converted samples are always processed according to the setting of theMAVE bits for AUX/TEMP before zone detection takes effect. See Table 30 for thresholds.

Table 24. Zone Detection Bit Definition

TZ1/AZ1 TZ0/AZ0 FUNCTION

0 0 Zone detection is disabled.0 1 When the processed data is below low threshold1 0 When the processed data is between low and high thresholds1 1 When the processed data is above high threshold

MAVE (default is 00000) — MAV filter function enable bit. When the corresponding bit is set to 1, the MAV filtersetup is applied to the corresponding measurement.

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Converter Function Select Register

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The Converter Function Select (CFN) register reflects the converter function select status.

Table 25. Converter Function Select Status Register (Reset Value = 0000h)MSB LSBD15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

CFN15 CFN14 CFN13 CFN12 CFN11 CFN10 CFN9 CFN8 CFN7 CFN6 CFN5 CFN4 CFN3 CFN2 CFN1 CFN0

CFN15-CFN0— Converter function select status. These bits represent the converter function currently running,which is set in bits C3-C0 of Control Byte 1. When the CFNx bit shows '1', where x is the decimal value ofconverter function select bits C3-C0, it indicates that the converter function that is set in bits C3-C0 is running.For example, when CFN2 shows '1', it indicates the converter function set in bits C3-C0 ('0010') is running. TheCFNx bits are reset to 0000h whenever the converter function is complete, stopped by STS bit, or reset (by thehardware reset from the RESET pin or the software reset from SWRST bit in Control Byte 1). However, if theTSC-initiated scan function mode is issued (by setting the PSM bit in the CFR0 register to '1'), the CFN0 orCFN1 bit will not be reset when the corresponding converter function is complete because there is no pen touch.This event allows the TSC2005 to immediately initiate the scan process (corresponding to CFN0 or CFN1 set to'1') when the next pen touch is detected.

Table 26. STATUS Register (Reset Value = 0004h)MSB LSBD15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

DAV DAV DAV DAV DAV DAV DAV

RESRVD RESET X Y RESRVD YDue Due Due Due Due Due Due PDST ID1 ID0(read '0') Flag CON CON (read '0') SHRX Y Z1 Z2 AUX TEMP1 TEMP2

DAV Bits— Data available bits. These seven bits mirror the operation of the internal signals of DAV. When anyprocessed data are stored in data registers, the corresponding DAV bit is set to '1'. It stays at '1' until theregister(s) updated to the processed data have been read out by the host.

Table 27. DAV Function

DAV DESCRIPTION

0 No new processed data are available.1 Processed data are available. This bit stays at 1 until the host has read out all updated registers.

RESET Flag— See Table 28 for the interpretation of the RESET flag bits.

Table 28. RESET Flag Bits

RESET Flag DESCRIPTION

0 Device was reset since last status poll (hardware or software reset).1 Device has not been reset since last status poll.

X CON— This bit is '1' if the X axis of the touch screen panel is properly connected to the X drivers. This bit is theconnection test result.

Y CON— This bit is '1' if the Y axis of the touch screen panel is properly connected to the Y drivers. This bit is theconnection test result.

Y SHR— This bit is '1' if there is no short-circuit tested at the Y axis of the touch screen panel. This bit is theshort-circuit test result.

PDST— Power down status. This bit reflects the setting of the PND0 bit in Control Byte 0. When this bit shows '0',it indicates A/D converter bias circuitry is still powered on after each conversion and before the next sampling;otherwise, it indicates A/D converter bias circuitry is powered down after each conversion and before the nextsampling. However, it is powered down between conversion sets. Because this status bit is synchronized withthe internal clock, it does not reflect the setting of the PND0 bit until a pen touch is detected or a converterfunction is running.

ID[1:0] Device ID bits: These bits represent the version ID of TSC2005. This version defaults to '00'.

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DATA REGISTERS

X, Y, Z1, Z2, AUX, TEMP1 and TEMP2 REGISTERS

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The data registers of the TSC2005 hold data results from conversions. All data registers default to 0000h upondevice reset.

The results of all A/D conversions are placed in the appropriate data registers, as described in Table 10 . Thedata format of the result word (R) of these registers is right-justified, as shown in Table 29 :

Table 29. Internal Register FormatMSB LSBD15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0

The TSC2005 has several 16-bit registers that allow control of the device, as well as providing a location to storeresults from the TSC2005 until read out by the host microprocessor. Table 30 shows the memory map.

Table 30. Register Content and Reset Values

(1)

RESETA3-A0 REGISTER VALUE(HEX) NAME D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 (HEX)

0 X 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

1 Y 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

2 Z1 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

3 Z2 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

4 AUX 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

5 Temp1 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

6 Temp2 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

Rsvd7 Status S15 S14 S13 S12 S11 S10 S9 0 S7 S6 S5 S3 S2 S1 S0 0004(2)

8 AUX High 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0FFF

9 AUX Low 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

A Temp High 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0FFF

B Temp Low 0 0 0 0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000

C CFR0 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 4000

D CFR1 0 0 0 0 R11 R10 R9 R8 0 0 0 0 0 R2 R1 R0 0000

E CFR2 R15 R14 R13 R12 R11 R10 R9 R8 R7 R6 0 R4 R3 R2 R1 R0 0000

Converter

RsvdF Function R15 R14 R13 R12 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 0000(2)Select Status

(1) For all combination bits, the pattern marked as reserved must not be used. The default pattern is read back after reset.(2) This bit is reserved.

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RESET

State Nor am l erai nOp t o Resetting InitialCondition

t <5 sm

WL(RESET)

t 10³ m

WL(RESET) s

tRtR

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

There are three way to reset the TSC2005. First, at power-on, a power good signal will generate a prolongedreset pulse internally to all registers.

Second, an external pin, RESET, is available to perform a system reset or allow other peripherals (such as adisplay) to reset the device if the pulse meets the timing requirement (at least 10 µs wide). Any RESET pulse lessthan 5 µs is rejected. To accommodate the timing drift between devices because of process variation, a RESETpulse width between 5 µs to 10 µs falls into the gray area that will not be recognized and the result isundetermined; this situation should be avoided. Refer to Figure 31 for details. A good reset pulse must be low forat least 10 µs. There is an internal spike filter to reject spikes up to 20ns wide.

NOTE: See Timing Requirements for more information.

Figure 31. External Reset Timing

Finally, a software reset can be activated by writing a '1' to CB1.1 (bit 1 of control byte 1). It should be noted thisreset is not self-cleared, so the user must write a '0' to remove the software reset.

A reset clears all registers and loads default values. A power-on reset and external (hardware) reset takeprecedence over a software reset. If a software reset is not cleared by the user, it will be cleared by either apower-on reset or an external (hardware) reset.

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THEORY OF OPERATION

TOUCH SCREEN MEASUREMENTS

Conversion Controlled by TSC2005 Initiated by TSC2005 (TSMode 1)

tCOORDINATE +OH1

fOSC )2@ǒtPVS)tPRE)tSNS)OHDLY1

fOSC Ǔ)2@ǒN@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC ǓǓ

(5)

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

As noted previously in the discussion of the A/D converter, several operating modes can be used that allow greatflexibility for the host processor. This section examines these different modes.

In TSMode 1, before a pen touch can be detected, the TSC2005 must be programmed with PSM = 1 and one oftwo scan modes:1. X-Y-Z Scan (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0000); or2. X-Y Scan (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0001).

See Table 7 for more information on the converter function select bits.

When the touch panel is touched, and the internal pen-touch signal to activates, the PINTDAV output is loweredif it is programmed as PENIRQ. The TSC2005 then executes the preprogrammed scan function without a hostintervention.

At the same time, the TSC2005 starts up its internal clock. It then turns on the Y-drivers, and after a programmedpanel voltage stabilization time, powers up the A/D converter and converts the Y coordinate. If preprocessing isselected, several conversions may take place. When data preprocessing is complete, the Y coordinate result isstored in a temporary register.

If the screen is still touched at this time, the X-drivers are enabled, and the process repeats, but measures the Xcoordinate instead, and stores the result in a temporary register.

If only X and Y coordinates are to be measured, then the conversion process is complete. A set of X and Ycoordinates are stored in the X and Y registers. Figure 32 shows a flowchart for this process. The time it takes togo through this process depends upon the selected resolution, internal conversion clock rate, panel voltagestabilization time, precharge and sense times, and whether preprocessing is selected. The time needed to get acomplete X and Y coordinate (sample set) reading can be calculated by:

Where:

COORDINATE

= time to complete X/Y coordinate reading.t

PVS

= panel voltage stabilization time, as given in Table 16 .t

PRE

= precharge time, as given in Table 17 .t

SNS

= sense time, as given in Table 18 .N = number of measurements for MAV filter input, as given in Table 3 as N.(For no MAV: M1-0[1:0] = '00', W1-0[1:0] = '00', N = 1.)B = number of bits of resolution.f

OSC

= TSC onboard OSC clock frequency. See Electrical Characteristics for supply frequency (SNSVDD).f

ADC

= A/D converter clock frequency, as given in Table 15 .OH1 = overhead time #1 = 2.5 internal clock cycles.OH

DLY1

= total overhead time for t

PVS

, t

PRE

, and t

SNS

= 10 internal clock cycles.OH

CONV

= total overhead time for A/D conversion = 3 internal clock cycles.L

PPRO

= pre-processor preocessing time as given in Table 31 .

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Programmedfor

Self-Control

X-YScanMode

(PSM=1)

(ControlByte1

D[6:3]=0001)

CS Deactivated

DetectingTouch

Sample,Conversion,and

Preprocessingfor

YCoordinate

Detecting

Touch

Sample,Conversion,and

Preprocessingfor

XCoordinate

Sample,Conversion,and

Preprocessingfor

YCoordinate

Detecting

Touch

Detecting

Touch

Reading

X-Data

Reading

Y-Data

TouchisDetected TouchisDetected

TouchisDetected

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

CFR2,D[15:14]=11or01

DAV,

As and ,

CFR2,D[15:14]=00

PENIRQ DAV

tCOORDINATE

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

Table 31. Preprocessing Delay

PPRO

M = W = FOR B = 12 BIT FOR B = 10 BIT

1 1, 4, 8, 16 2 23, 7 1 28 247 3 31 2715 1 31 2915 3 34 3215 7 38 36

Figure 32. Example of X and Y Coordinate Touch Screen Scan using TSMode 1

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tCOORDINATE +OH2

fOSC )3@ǒtPVS)tPRE)tSNS)OHDLY1

fOSC Ǔ)4@ǒN@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC ǓǓ

(6)

Programmedfor

Self-Control

(PSM=1)

X-Y-Z -Z ScanMode

(ControlByte1

D[6:3]=0000)

1 2

CS Deactivated

Sample,Conversion,

andPreprocessingfor

YCoordinate

Sample,Conversion,

andPreprocessingfor

XCoordinate

Sample,Conversion,

andPreprocessingfor

Z CoordinateandZ Coordinate

1 2

Sample,Conversion,

andPreprocessingfor

YCoordinate

Reading

X-Data

TouchisDetected

Detecting

Touch

Detecting

Touch

Detecting

Touch

Detecting

Touch

Reading

Y-Data

Reading

Z -Data

Reading

Z -Data

TouchisDetected TouchisDetected

TouchisDetected

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

As ,

CFR2,D[15:14]=11or01

DAV

As and ,

CFR2,D[15:14]=00

PENIRQ DAV

tCOORDINATE

Detecting

Touch

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

If the pressure of the touch is also to be measured, the process continues in the same way, but measuring the Z

1and Z

values instead, and storing the results in temporary registers. Once the complete sample set of data (X,Y, Z

, and Z

) are available, they are loaded in the X, Y, Z

, and Z

registers. This process is illustrated inFigure 33 . As before, this process time depends upon the settings previously described. The time for a completeX, Y, Z

, and Z

coordinate reading is given by:

Where:

OH2 = overhead time #2 = 3.5 internal clock cycles.

Figure 33. Example of X, Y, and Z Coordinate Touch Screen Scan using TSMode 1

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Conversion Controlled by TSC2005 Initiated by Host (TSMode 2)

tCOORDINATE +OH1

fOSC )2@ǒtPVS)tPRE)tSNS)OHDLY1

fOSC Ǔ)2@ǒN@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC ǓǓ

(7)

Detecting

Touch

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

As ,

CFR2,D[15:14]=11or01

DAV

As and ,

CFR2,D[15:14]=00

PENIRQ DAV

Programmed

for

Host-

Controlled

Mode

(PSM=0)

Deactivated P ograr mm d

for

X-Y

ScanMode

eReading

X-Data

WaitingforHostto

WriteInto

ControlByte1D[6:3]

Sample,Conversion,

andPreprocessingfor

YCoordinate

TouchisStillHere

Reading

Y-Data

Deactivated

Detecting

Touch

TouchisDetected

Sample,Conversion,

andPreprocessingfor

XCoordinate

Detecting

Touch

Sample,Conversion,

andPreprocessingfor

YCoordinate

Detecting

Touch

tCOORDINATE

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

In TSMode 2, the TSC2005 detects when the touch panel is touched and causes the internal Pen-Touch signalto activate, which lowers the PINTDAV output if it is programmed as PENIRQ. The host recognizes the interruptrequest, and then writes to the A/D Converter Control register to select one of the two touch screen scanfunctions:

1. X-Y-Z Scan (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0000); or2. X-Y Scan (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0001).

See Table 7 for more information on the converter function select bits.

The conversion process then as shown in Figure 34 ; see previous sections for more details.

The main difference between this mode and the previous mode is that the host, not the TSC2005, decides whenthe touch screen scan begins.

The time needed to convert both X and Y coordinates under host control (not including the time needed to sendthe command over the SPI bus) is given by:

Figure 34. Example of an X and Y Coordinate Touch Screen Scan using TSMode 2

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Conversion Controlled by Host (TSMode 3)

tCOORDINATE +OH1

fOSC )ǒtPRE)tSNS)OHDLY2

fOSC Ǔ)N@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC Ǔ

(8)

Programmed

forHost-

Controlled

Mode

(PSM=0)

Deactivated X

Scan

Mode

Programmedfor:

TurnOn

X+and

Drivers

(1)

Reading

Y-Data

TouchisDetected

Deactivated

NOTE:(1)Optional.Ifnotturnedon,itwillbeturnedonbytheScanmode,oncedetected.

Scan

Mode

Programmedfor:

TurnOn

Y+and

Drivers

(1)

Reading

X-Data

Deactivated

Detecting

Touch

WaitingforHosttoWriteInto

ControlByte1D[6:3]

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

As ,

CFR2,D[15:14]=11or01

DAV

As and ,

CFR2,D[15:14]=00

PENIRQ DAV

TouchisDetected TouchisDetected

Sample,Conversion,

andPreprocessing

forXCoordinate

Detecting

Touch

Sample,Conversion,

andPreprocessing

forYCoordinate

Detecting

Touch

WaitingforHostto

WriteIntoControl

Byte1D[6:3]

WaitingforHosttoWriteInto

ControlByte1D[6:3]

tCOORDINATE tCOORDINATE

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

In TSMode 3, the TSC2005 detects when the touch panel is touched and causes the internal Pen-Touch signalto be active, which lowers the PINTDAV output if it is programmed as PENIRQ. The host recognizes the interruptrequest. Instead of starting a sequence in the TSC2005, which then reads each coordinate in turn, the host mustnow control all aspects of the conversion. Generally, upon receiving the interrupt request, the host turns on the Xdrivers. ( NOTE: If drivers are not turned on, the device detects this condition and turns them on before the scanstarts. This situation is why the event of turn on drivers is shown as optional in Figure 35 and Figure 36 .) Afterwaiting for the settling time, the host then addresses the TSC2005 again, this time requesting an X coordinateconversion.

The process is then repeated for the Y and Z coordinates. The processes are outlined in Figure 35 andFigure 36 .Figure 35 shows two consecutive scans on X and Y. Figure 36 shows a single Z scan.

The time needed to convert any single coordinate X or Y under host control (not including the time needed tosend the command over the SPI bus) is given by:

Where:

DLY2

= total overhead time for t

PRE

and t

SNS

= 6 internal clock cycles.

Figure 35. Example of X and Y Coordinate Touch Screen Scan using TSMode 3

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tCOORDINATE +OH2

fOSC )ǒtPRE)tSNS)OHDLY2

fOSC Ǔ)N@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC Ǔ

(9)

NOTE:(1)Optional.Ifnotturnedon,itwillbeturnedonbytheScanmode,oncedetected.

Detecting

Touch

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

As ,

CFR2,D[15:14]=11or01

DAV

As and ,

CFR2D[15:14]=00

PENIRQ DAV

Programmed

for

Host-Controlled

Mode

(PSM=0)

Deactivated Z

Scan

Mode

Reading

Z -Data

WaitingforHosttoWrite

IntoControlByte1D[6:3]

TouchisDetected

Reading

Z -Data

Deactivated

Detecting

Touch

WaitingforHosttoWrite

IntoControlByte1D[6:3]

TouchisDetected

tCOORDINATE

TurnOn

Y+

and

Drivers

(1)

Programmedfor:

Sample,Conversion,

andPreprocessing

forZ Coordinate

Sample,Conversion,

andPreprocessing

forZ Coordinate

tCOORDINATE +OH2

fOSC )ǒtPVS)tPRE)tSNS)OHDLY1

fOSC Ǔ)N@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC Ǔ

(10)

Detecting

Touch

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

As ,

CFR2,D[15:14]=11or01

DAV

As and ,

CFR2D[15:14]=00

PENIRQ DAV

Programmedfor

Host-Controlled

Mode

(PSM=0)

Deactivated P ograr mm d

for

Z -Z

ScanMode

1 2

Reading

Z -Data

WaitingforHosttoWrite

IntoControlByte1D[6:3]

Sample,Conversion,and

PreprocessingforZ ,Z Coordinates

1 2

TouchisStillHere

Reading

Z -Data

Deactivated

Detecting

Touch

WaitingforHosttoWrite

IntoControlByte1D[6:3]

TouchisDetected

tCOORDINATE

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The time needed to convert any Z

and Z

coordinate under host control (not including the time needed to sendthe command over the SPI bus) is given by:

Figure 36. Example of Z

and Z

Coordinate Touch Screen Scan(without Panel Stabilization Time) using TSMode 3

If the drivers are not turned on befire the touch screen mode is programmed, the panel stabilization time shouldbe included. In this case, the time needed to convert an single X or Y under host control (not including the timeneeded to send the command over the SPI bus) is given by:

Figure 37. Example of a Z

and Z

Coordinate Touch Screen Scan(with Panel Stabilization Time) using TSMode 3

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tCOORDINATE +OH1

fOSC )ǒtPVS)tPRE)tSNS)OHDLY1

fOSC Ǔ)N@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC Ǔ

(11)

Detecting

Touch

PINTDAV Programmed:

As ,

CFR2,D[15:14]=10

PENIRQ

As ,

CFR2,D[15:14]=11or01

DAV

As and ,

CFR2,D[15:14]=00

PENIRQ DAV

Programmedfor

Host-Controlled

Mode

(PSM=0)

Deactivated

P ograr mm d

for

ScanMode

eReading

X-Data

Detecting

Touch

WaitingforHosttoWrite

IntoControlByte1D[6:3]

Sample,Conversion,and

PreprocessingforXCoordinate

WaitingforHosttoWrite

IntoControlByte1D[6:3]

TouchisDetected

TouchisStillHere

tCOORDINATE

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The time needed to convert any single coordinate (either X or Y) under host control (not including the timeneeded to send the command over the SPI bus) is given by:

Figure 38. Example of a Single X Coordinate Touch Screen Scan(with Panel Stabilization Time) using TSMode 3

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AUXILIARY AND TEMPERATURE MEASUREMENT

tCOORDINATE +OH3

fOSC )N@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC Ǔ

(12)

Deactivated

NoTouch

Detected

HostWriteto

ControlByte1D[6:3]

As DAV

WaitingforHostto

ReadAUXData

Deactivated Reading

AUX-Data

Sample,Conversion,and

AveragingforAUXMeasurement

Deactivated

P ograr mm dfor

Non-Continuous

AUXMeasurement

tCOORDINATE

NoTouch

Detected

tCOORDINATE +OH3

fOSC )N@ǒ(B)2)@fOSC

fADC )OHCONVǓ@ǒ1

fOSCǓ)ǒLPPRO

fOSC Ǔ

(13)

Deactivated

NoTouch

Detected

HosttoWriteto

ControlByte1D[6:3]

As DAV

Deactivated Reading

AUX-Data

Sample,Conversion,

andAveragingfor

AUXMeasurement

Deactivated

P ograr mm dfor

Continuous

AUXMeasurement

eCS

Deactivated

Reading

AUX-Data

tCOORDINATE tCOORDINATE tCOORDINATE

Sample,Conversion,

andAveragingfor

AUXMeasurement

Sample,Conversion,

andAveragingfor

AUXMeasurement

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The TSC2005 can measure the voltage from the auxiliary input (AUX) and from the internal temperature sensor.Applications for the AUX can include external temperature sensing, ambient light monitoring for controllingbacklighting, or sensing the current drawn from batteries. There are two converter functions that can be used forthe measurement of the AUX:1. Non-continuous AUX measurement shown in Figure 39 (converter function select bits C[3:0] = Control Byte 1D[6:3] = 0101); or2. Continuous AUX Measurement shown in Figure 40 (converter function select bits C[3:0] = Control Byte 1D[6:3] = 1000).

See Table 7 for more information on the converter function select bits.

There are also two converter functions for the measurement of the internal temperature sensor:1. TEMP1 measurement (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0110); or2. TEMP2 measurement (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0111).

See Table 7 for more information on the converter function select bits.

For the detailed calculation of the internal temperature sensor, please see the SubSec1 9.3 section. These twoconverter functions have the same timing as the non-continuous AUX measurement operation as shown inFigure 39 ; therefore, Equation 12 can also be used for internal temperature sensor measurement. The timeneeded to make a non-continuous auxiliary measurement or an internal temperature sensor measurement isgiven by:

Where:

OH3 = overhead time #3 = 3.5 internal clock cycles.

Figure 39. Non-Touch Screen, Non-Continuous AUX Measurement

The time needed to make continuous auxiliary measurement is given by:

Figure 40. Non-Touch Screen, Continuous AUX Measurement

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LAYOUT

TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

The following layout suggestions should obtain optimum performance from the TSC2005. However, manyportable applications have conflicting requirements for power, cost, size, and weight. In general, most portabledevices have fairly clean power and grounds because most of the internal components are very low power. Thissituation would mean less bypassing for the converter power and less concern regarding grounding. Still, eachapplication is unique and the following suggestions should be reviewed carefully.

For optimum performance, care should be taken with the physical layout of the TSC2005 circuitry. The basicSAR architecture is sensitive to glitches or sudden changes on the power supply, reference, ground connections,and digital inputs that occur just prior to latching the output of the analog comparator. Therefore, during anysingle conversion for an n-bit SAR converter, there are nwindows in which large external transient voltages caneasily affect the conversion result. Such glitches might originate from switching power supplies, nearby digitallogic, and high power devices. The degree of error in the digital output depends on the reference voltage, layout,and the exact timing of the external event. The error can change if the external event changes in time withrespect to the SCLK input.

With this in mind, power to the TSC2005 should be clean and well-bypassed. A 0.1 µF ceramic bypass capacitorshould be added between (SNSVDD to AGND and SNSGND) or (I/OVDD to DGND). A 0.1 µF decouplingcapacitor between VREF to AGND is also needed unless the SNSVDD is used as a reference input and isconnected to VREF. These capacitors must be placed as close to the device as possible. A 1 µF to 10 µFcapacitor may also be needed if the impedance of the connection between SNSVDD and the power supply ishigh. The I/OVDD must be shorted to the same supply plane as the SNSVDD. Short both SNSVDD and I/OVDDto the analog VDD plane.

The A/D converter architecture offers no inherent rejection of noise or voltage variation in regards to using anexternal reference input, which is of particular concern when the reference input is tied to the power supply forauxiliary input and temperature measurements. Any noise and ripple from the supply appears directly in thedigital results. While high-frequency noise can be filtered out by the built-in MAV filter, voltage variation due toline frequency (50Hz or 60Hz) can be difficult to remove. Some package options have pins labeled as NC (noconnection). It is recommended that these NC pins be connected to the ground plane. Avoid any active tracegoing under the analog pins listed in the Pin Assignments table, unless they are shielded by a ground or powerplane.

All GND (AGND, DGND, SUBGND and SNSGND) pins should be connected to a clean ground point. In manycases, this point is the analog ground. Avoid connections that are too near the grounding point of amicrocontroller or digital signal processor. If needed, run a ground trace directly from the converter to thepower-supply entry or battery connection point. The ideal layout includes an analog ground plane dedicated tothe converter and associated analog circuitry.

In the specific case of use with a resistive touch screen, care should be taken with the connection between theconverter and the touch screen. Since resistive touch screens have fairly low resistance, the interconnectionshould be as short and robust as possible. Loose connections can be a source of error when the contactresistance changes with flexing or vibrations.

As indicated previously, noise can be a major source of error in touch-screen applications (for example,applications that require a back-lit LCD panel). This electromagnetic interfence (EMI) noise can be coupledthrough the LCD panel to the touch screen and cause flickering of the converted A/D converter data. Severalthings can be done to reduce this error; for example, use a touch screen with a bottom-side metal layerconnected to ground to couple the majority of noise to ground. Another way to filter out this type of noise is byusing the TSC2005 built-in MAV filter (see the Preprocessing setion). Filtering capacitors, from Y+, Y – , X+, andX – to ground, can also help. Note, however, that the use of these capacitors increases screen settling time andrequires longer panel voltage stabilization times, and also increases precharge and sense times for the PINTADVcircuitry of the TSC2005. The resistor value varies, depending on the touch screen sensor used. The internal50k Ωpull-up resistor (R

IRQ

) may be adequate for most of sensors.

Product Folder Link(s): TSC2005

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TSC2005

SBAS379C – DECEMBER 2006 – REVISED MARCH 2008

REVISION HISTORYNOTE: Page numbers for previous revisions may differ from page numbers in the current version.

Changes from Revision B (December 2007) to Revision C ........................................................................................... Page

•Changed resistance ratio from 80 to 91 .............................................................................................................................. 13•Changed resistance ratio from 80 to 91 .............................................................................................................................. 13•Changed T factor from 2.648 to 2.573 ................................................................................................................................ 13•Swapped funtion text of 1011 with 1100 in Table 7 ............................................................................................................. 20•Changed "Y-axis" to "X-axis" in 1011 function text in Table 7 ............................................................................................. 20•Swapped text from C3-C0 = 1011 with text from 1011........................................................................................................ 21•Changed "Y-axis" to "X-axis" in C3-C0 = 1011 text ............................................................................................................. 21

Changes from Revision A (May, 2007) to Revision B ..................................................................................................... Page

•Changed ADC to A/D converter throughout document ......................................................................................................... 1•Changed 51k Ωto 50k Ωthroughout document except in the Electrical Characteristic table ................................................. 1•Changed Power-Supply Requirements section of Electrical Characteristic table ................................................................. 3•Changed Power-down supply current condtion, and typical value from 0 to 0.023 .............................................................. 3•Changed Pin Assignments table ............................................................................................................................................ 5•Changed first five rows of Timing Requirements table .......................................................................................................... 6•Changed Figure 4 .................................................................................................................................................................. 7•Added Figure 5 ..................................................................................................................................................................... 7•Changed LSM paragraph. .................................................................................................................................................... 26•Changed CFN15-CFN0 paragraph ...................................................................................................................................... 29•Added note to Figure 31 ...................................................................................................................................................... 31•Changed Equation 8 ; moved paren. .................................................................................................................................... 36•Changed Equation 9 ; moved paren. .................................................................................................................................... 37•Changed Equation 10 ; moved paren. .................................................................................................................................. 37•Changed Equation 11 ; moved paren. .................................................................................................................................. 38•Changed Equation 12 ; moved paren. .................................................................................................................................. 39•Changed Equation 13 ; moved paren. .................................................................................................................................. 39•Changed Layout section ...................................................................................................................................................... 40

Product Folder Link(s): TSC2005

PACKAGE OPTION ADDENDUM

www.ti.com 21-May-2010

Addendum-Page 1

PACKAGING INFORMATION

Orderable Device Status (1) Package Type Package

Drawing Pins Package Qty Eco Plan (2) Lead/

Ball Finish MSL Peak Temp (3) Samples

(Requires Login)

TSC2005IYZLR ACTIVE DSBGA YZL 28 3000 Green (RoHS

& no Sb/Br) SNAGCU Level-1-260C-UNLIM

TSC2005IYZLT ACTIVE DSBGA YZL 28 250 Green (RoHS

& no Sb/Br) SNAGCU Level-1-260C-UNLIM

(1) The marketing status values are defined as follows:

ACTIVE: Product device recommended for new designs.

LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.

NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.

PREVIEW: Device has been announced but is not in production. Samples may or may not be available.

OBSOLETE: TI has discontinued the production of the device.

(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability

information and additional product content details.

TBD: The Pb-Free/Green conversion plan has not been defined.

Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that

lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.

Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between

the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.

Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight

in homogeneous material)

(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.

Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information

provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and

continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.

TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.

In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.

TAPE AND REEL INFORMATION

*All dimensions are nominal

Device Package

Type Package

Drawing Pins SPQ Reel

Diameter

(mm)

Reel

Width

W1 (mm)

(mm) B0

(mm) K0

(mm) P1

(mm) W

(mm) Pin1

Quadrant

TSC2005IYZLR DSBGA YZL 28 3000 180.0 8.4 2.75 3.25 0.81 4.0 8.0 Q1

TSC2005IYZLT DSBGA YZL 28 250 180.0 8.4 2.75 3.25 0.81 4.0 8.0 Q1

PACKAGE MATERIALS INFORMATION

www.ti.com 22-Sep-2011

Pack Materials-Page 1

*All dimensions are nominal

Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)

TSC2005IYZLR DSBGA YZL 28 3000 210.0 185.0 35.0

TSC2005IYZLT DSBGA YZL 28 250 210.0 185.0 35.0

PACKAGE MATERIALS INFORMATION

www.ti.com 22-Sep-2011

Pack Materials-Page 2

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