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ADC0844/ADC0848 8-Bit μP Compatible A/D Converters with Multiplexer Options
Check for Samples: ADC0844,ADC0848
1FEATURES DESCRIPTION
The ADC0844 and ADC0848 are CMOS 8-bit
2• Easy Interface to All Microprocessors successive approximation A/D converters with
• Operates Ratiometrically or with 5 VDC Voltage versatile analog input multiplexers. The 4-channel or
Reference 8-channel multiplexers can be software configured for
• No Zero or Full-Scale Adjust Required single-ended, differential or pseudo-differential modes
of operation.
• 4-Channel or 8-Channel Multiplexer with
Address Logic The differential mode provides low frequency input
common mode rejection and allows offsetting the
• Internal Clock analog range of the converter. In addition, the A/D's
• 0V to 5V Input Range with Single 5V Power reference can be adjusted enabling the conversion of
Supply reduced analog ranges with 8-bit resolution.
• Standard Width 20-Pin or 24-Pin PDIP The A/Ds are designed to operate from the control
• 28 Pin PLCC Package bus of a wide variety of microprocessors. TRI-STATE
output latches that directly drive the data bus permit
KEY SPECIFICATIONS the A/Ds to be configured as memory locations or I/O
devices to the microprocessor with no interface logic
• Resolution: 8 Bits necessary.
• Total Unadjusted Error: ±½ LSB and ± 1 LSB
• Single Supply: 5 VDC
• Low Power: 15 mW
• Conversion Time: 40 μs
Block Diagram
* ADC0848 shown in PDIP Package CH5-CH8 not included on the ADC0844
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 1999–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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Connection Diagram
Figure 1. PLCC Package (Top View) Figure 2. 20-Pin PDIP (Top View)
Figure 3. 28-Pin PDIP (Top View)
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
Absolute Maximum Ratings(1)(2)(3)
Supply Voltage (VCC) 6.5V
Logic Control Inputs −0.3V to +15V
Voltage At Other Inputs and Outputs −0.3V to VCC+0.3V
Input Current at Any Pin(4) 5 mA
Package Input Current(4) 20 mA
Storage Temperature −65°C to +150°C
Package Dissipation at TA=25°C 875 mW
ESD Susceptibility(5) 800V
PDIP Package 260°C
Lead Temperature (Soldering, 10 seconds) Vapor Phase (60 seconds) 215°C
PLCC Package Infrared (15 seconds) 220°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not
apply when operating the device beyond its specified operating conditions.
(2) All voltages are measured with respect to the ground pins.
(3) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
(4) When the input voltage (VIN) at any pin exceeds the power supply rails (VIN < V−or VIN > V+) the absolute value of the current at that pin
should be limited to 5 mA or less. The 20 mA package input current limits the number of pins that can exceed the power supply
boundaries with a 5 mA current limit to four.
(5) Human body model, 100 pF discharged through a 1.5 kΩresistor.
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Operating Conditions(1)(2)
Supply Voltage (VCC) 4.5 VDC to 6.0 VDC
ADC0844CCN, ADC0848BCN, ADC0848CCN 0°C≤TA≤70°C
Temperature Range (TMIN≤TA≤TMAX)ADC0844BCJ(3), ADC0844CCJ(3), ADC0848BCV, −40°C≤TA≤85°C
ADC0848CCV
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not
apply when operating the device beyond its specified operating conditions.
(2) All voltages are measured with respect to the ground pins.
(3) Product/package combination obsolete; shown for reference only.
Electrical Characteristics
The following specifications apply for VCC = 5 VDC unless otherwise specified. Boldface limits apply from TMIN to TMAX;all
other limits TA= Tj= 25°C. ADC0844CCN,
ADC0848BCN,
ADC0844BCJ(1) ADC0848CCN,
ADC0844CCJ(1) Limit
ADC0848BCV,
Parameter Conditions Units
ADC0848CCV
Tested Design Tested Design
Typ(2) Typ(2)
Limit(3) Limit(4) Limit(3) Limit(4)
CONVERTER AND MULTIPLEXER CHARACTERISTICS
Maximum Total
ADC0844BCN, ±½ ±½ LSB
ADC0848BCN, BCV VREF = 5.00 VDC(5)
Unadjusted ADC0844CCN,
Error ±1 ±1 LSB
ADC0848CCN, CCV
ADC0844CCJ(1) ±1 LSB
Minimum Reference Input Resistance 2.4 1.1 2.4 1.2 1.1 kΩ
Maximum Reference Input Resistance 2.4 5.9 2.4 5.4 5.9 kΩ
VCC +VCC +VCC +
Maximum Common-Mode Input Voltage See(6) V
0.05 0.05 0.05
GND −GND −GND −
Minimum Common-Mode Input Voltage See(6) V
0.05 0.05 0.05
DC Common-Mode Error Differential Mode ±1/16 ±¼ ±1/16 ±¼ ±¼ LSB
Power Supply Sensitivity VCC = 5V±5% ±1/16 ±⅛±1/16 ±⅛±⅛LSB
On Channel = 5V, Off −1−0.1 −1μA
Channel = 0V(7)
Off Channel Leakage Current On Channel = 0V, Off 10.1 1μA
Channel = 5V
DIGITAL AND DC CHARACTERISTICS
VIN(1), Logical “1” Input Voltage (Min) VCC = 5.25V 2.0 2.0 2.0 V
VIN(0), Logical “0” Input Voltage (Max) VCC = 4.75V 0.8 0.8 0.8 V
IIN(1), Logical “1” Input Current (Max) VIN = 5.0V 0.005 10.005 1μA
IIN(0), Logical “0” Input Current (Max) VIN = 0V −0.005 −1−0.005 −1μA
(1) This product/package combination is obsolete. Shown for reference only.
(2) Typical figures are at 25°C and represent most likely parametric norm.
(3) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).
(4) Design limits are specified by not 100% tested. These limits are not used to calculate outgoing quality levels.
(5) Total unadjusted error includes offset, full-scale, linearity, and multiplexer error.
(6) For VIN (−)≥VIN(+) the digital output code will be 0000 0000. Two on-chip diodes are tied to each analog input, which will forward-
conduct for analog input voltages one diode drop below ground or one diode drop greater than VCC supply. Be careful during testing at
low VCC levels (4.5V), as high level analog inputs (5V) can cause this input diode to conduct, especially at elevated temperatures, and
cause errors for analog inputs near full-scale. The spec allows 50 mV forward bias of either diode. This means that as long as the
analog VIN does not exceed the supply voltage by more than 50 mV, the output code will be correct. To achieve an absolute 0 VDC to 5
VDC input voltage range will therefore require a minimum supply voltage of 4.950 VDC over temperature variations, initial tolerance and
loading.
(7) Off channel leakage current is measured after the channel selection.
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Electrical Characteristics (continued)
The following specifications apply for VCC = 5 VDC unless otherwise specified. Boldface limits apply from TMIN to TMAX;all
other limits TA= Tj= 25°C. ADC0844CCN,
ADC0848BCN,
ADC0844BCJ(1) ADC0848CCN,
ADC0844CCJ(1) Limit
ADC0848BCV,
Parameter Conditions Units
ADC0848CCV
Tested Design Tested Design
Typ(2) Typ(2)
Limit(3) Limit(4) Limit(3) Limit(4)
VCC = 4.75V, IOUT =−360 μA2.4 2.8 2.4 V
VOUT(1), Logical “1” Output Voltage (Min) IOUT =−10 μA4.5 4.6 4.5 V
VOUT(0), Logical “0” Output Voltage (Max) VCC = 4.75V, IOUT = 1.6 mA 0.4 0.34 0.4 V
VOUT = 0V −0.01 −3−0.01 −0.3 −3μA
IOUT, TRI-STATE Output Current (Max) VOUT = 5V 0.01 30.01 0.3 3μA
ISOURCE, Output Source Current (Min) VOUT = 0V −14 −6.5 −14 −7.5 −6.5 mA
ISINK, Output Sink Current (Min) VOUT = VCC 16 8.0 16 9.0 8.0 mA
ICC, Supply Current (Max) CS = 1, VREF Open 1 2.5 1 2.3 2.5 mA
AC Electrical Characteristics
The following specifications apply for VCC = 5VDC, tr= tf= 10 ns unless otherwise specified. Boldface limits apply from TMIN
to TMAX;all other limits TA= Tj= 25°C. Tested Design
Parameter Conditions Typ(1) Units
Limit(2) Limit(3)
tC, Maximum Conversion Time (See Figure 7) 30 40 60 μs
tW(WR), Minimum WR Pulse Width See(4) 50 150 ns
tACC, Maximum Access Time (Delay from Falling Edge of RD to CL= 100 pF(4) 145 225 ns
Output Data Valid)
t1H, t0H, TRI-STATE Control (Maximum Delay from Rising Edge of CL= 10 pF, RL= 10k(4) 125 200 ns
RD to Hi-Z State)
tWI, tRI, Maximum Delay from Falling Edge of WR or RD to Reset 200 400 ns
of INTR See(4)
tDS, Minimum Data Set-Up Time 50 100 ns
tDH, Minimum Data Hold Time 0 50 ns
CIN, Capacitance of Logic Inputs 5 pF
COUT, Capacitance of Logic Outputs 5 pF
(1) Typical figures are at 25°C and represent most likely parametric norm.
(2) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).
(3) Design limits are specified by not 100% tested. These limits are not used to calculate outgoing quality levels.
(4) The temperature coefficient is 0.3%/°C.
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Typical Performance Characteristics
Logic Input Threshold Voltage
vs. Supply Voltage Output Current vs. Temperature
Figure 4. Figure 5.
Power Supply Current vs. Temperature Linearity Error vs. VREF
Figure 6. Figure 7.
Conversion Time vs. VSUPPLY Conversion Time vs.Temperature
Figure 8. Figure 9.
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Typical Performance Characteristics (continued)
Unadjusted Offset Error vs.
VREF Voltage
Figure 10.
TRI-STATE Test Circuits and Waveforms
t1H t1H, CL= 10 pF
t0H t0H, CL= 10 pF
tr= 20 ns
Leakage Current Test Circuit
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Timing Diagrams
Read strobe must occur at least 600 ns after the assertion of interrupt to ensure reset of INTR .
MA stands for MUX address.
Figure 11. Using the Previously Selected Channel Configuration and Starting a Conversion
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Functional Description
The ADC0844 and ADC0848 contain a 4-channel and 8-channel analog input multiplexer (MUX) respectively.
Each MUX can be configured into one of three modes of operation differential, pseudo-differential, and single
ended. These modes are discussed in Applications Information. The specific mode is selected by loading the
MUX address latch with the proper address (see Table 1 and Table 2). Inputs to the MUX address latch (MA0-
MA4) are common with data bus lines (DB0-DB4) and are enabled when the RD line is high. A conversion is
initiated via the CS and WR lines. If the data from a previous conversion is not read, the INTR line will be low.
The falling edge of WR will reset the INTR line high and ready the A/D for a conversion cycle. The rising edge of
WR, with RD high, strobes the data on the MA0/DB0-MA4/DB4 inputs into the MUX address latch to select a
new input configuration and start a conversion. If the RD line is held low during the entire low period of WR the
previous MUX configuration is retained, and the data of the previous conversion is the output on lines DB0-DB7.
After the conversion cycle (tC≤40 μs), which is set by the internal clock frequency, the digital data is transferred
to the output latch and the INTR is asserted low. Taking CS and RD low resets INTR output high and outputs the
conversion result on the data lines (DB0-DB7).
APPLICATIONS INFORMATION
MULTIPLEXER CONFIGURATION
The design of these converters utilizes a sampled-data comparator structure which allows a differential analog
input to be converted by a successive approximation routine.
The actual voltage converted is always the difference between an assigned “+” input terminal and a “−” input
terminal. The polarity of each input terminal of the pair being converted indicates which line the converter expects
to be the most positive. If the assigned “+” input is less than the “−” input the converter responds with an all zeros
output code.
A unique input multiplexing scheme has been utilized to provide multiple analog channels. The input channels
can be software configured into three modes: differential, single ended, or pseudo-differential. Figure 12 shows
the three modes using the 4-channel MUX ADC0844. The eight inputs of the ADC0848 can also be configured in
any of the three modes. In the differential mode, the ADC0844 channel inputs are grouped in pairs, CH1 with
CH2 and CH3 with CH4. The polarity assignment of each channel in the pair is interchangeable. The single-
ended mode has CH1–CH4 assigned as the positive input with the negative input being the analog ground
(AGND) of the device. Finally, in the pseudo-differential mode CH1–CH3 are positive inputs referenced to CH4
which is now a pseudo-ground. This pseudo-ground input can be set to any potential within the input common-
mode range of the converter. The analog signal conditioning required in transducer-based data acquisition
systems is significantly simplified with this type of input flexibility. One converter package can now handle ground
referenced inputs and true differential inputs as well as signals with some arbitrary reference voltage.
The analog input voltages for each channel can range from 50 mV below ground to 50 mV above VCC (typically
5V) without degrading conversion accuracy.
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Table 1. ADC0844 MUX ADDRESSING(1)
MUX Address Channel#
CS WR RD MUX Mode
MA3 MA2 MA1 MA0 CH1 CH2 CH3 CH4 AGND
X L L L L H + −
X L L H L NP H −+Differential
X L H L L H + −
X L H H L H −+
L H L L L H + −
L H L H L NP H + −Single-Ended
L H H L L H + −
L H H H L H + −
H H L L L H + −
H H L H L NP H + −Pseudo- Differential
H H H L L H + −
X X X X L NP L Previous Channel Configuration
(1) X = don't care, NP = negative pulse
4 Single-Ended 2 Differential
3 Pseudo-Differential Combined
Figure 12. Analog Input Multiplexer Options
REFERENCE CONSIDERATIONS
The voltage applied to the reference input of these converters defines the voltage span of the analog input (the
difference between VIN(MAX) and VIN(MIN)) over which the 256 possible output codes apply. The devices can be
used in either ratiometric applications or in systems requiring absolute accuracy. The reference pin must be
connected to a voltage source capable of driving the minimum reference input resistance of 1.1 kΩ. This pin is
the top of a resistor divider string used for the successive approximation conversion.
In a ratiometric system (Figure 13), the analog input voltage is proportional to the voltage used for the A/D
reference. This voltage is typically the system power supply, so the VREF pin can be tied to VCC. This technique
relaxes the stability requirements of the system reference as the analog input and A/D reference move together
maintaining the same output code for a given input condition. For absolute accuracy (Figure 14), where the
analog input varies between very specific voltage limits, the reference pin can be biased with a time and
temperature stable voltage source. The LM385 and LM336 reference diodes are good low current devices to use
with these converters.
The maximum value of the reference is limited to the VCC supply voltage. The minimum value, however, can be
quite small (see Typical Performance Characteristics) to allow direct conversions of transducer outputs providing
less than a 5V output span. Particular care must be taken with regard to noise pickup, circuit layout and system
error voltage sources when operating with a reduced span due to the increased sensitivity of the converter (1
LSB equals VREF/256).
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THE ANALOG INPUTS
Analog Differential Voltage Inputs and Common-Mode Rejection
The differential input of these converters actually reduces the effects of common-mode input noise, a signal
common to both selected “+” and “−” inputs for a conversion (60 Hz is most typical). The time interval between
sampling the “+” input and then the “−” inputs is ½ of a clock period. The change in the common-mode voltage
during this short time interval can cause conversion errors. For a sinusoidal common-mode signal this error is:
where
• fCM is the frequency of the common-mode signal
• Vpeak is its peak voltage value
• tCis the conversion time
For a 60 Hz common-mode signal to generate a ¼ LSB error (≈5 mV) with the converter running at 40 μS, its
peak value would have to be 5.43V. This large a common-mode signal is much greater than that generally found
in a well designed data acquisition system.
Table 2. ADC0848 MUX Addressing(1)
MUX Address Channel
CS WR RD MUX Mode
MA4 MA3 MA2 MA1 MA0 CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH8 AGND
X L L L L L H + −
X L L L H L H −+
X L L H L L H + −
X L L H H L NP H −+Differential
X L H L L L H + −
X L H L H L H −+
X L H H L L H + −
X L H H H L H −+
L H L L L L H + −
L H L L H L H + −
L H L H L L H + −
L H L H H L NP H + −Single-Ended
L H H L L L H + −
L H H L H L H + −
L H H H L L H + −
L H H H H L H + −
H H L L L L H + −
H H L L H L H + −
H H L H L L H + −Pseudo-
H H L H H L NP H + −Differential
H H H L L L H + −
H H H L H L H + −
H H H H L L H + −
X X X X X L L Previous Channel Configuration
(1) X = don't care, NP = negative pulse
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Input Current
Due to the sampling nature of the analog inputs, short duration spikes of current enter the “+” input and exit the
“−” input at the clock edges during the actual conversion. These currents decay rapidly and do not cause errors
as the internal comparator is strobed at the end of a clock period. Bypass capacitors at the inputs will average
these currents and cause an effective DC current to flow through the output resistance of the analog signal
source. Bypass capacitors should not be used if the source resistance is greater than 1 kΩ.
Input Source Resistance
The limitation of the input source resistance due to the DC leakage currents of the input multiplexer is important.
A worst-case leakage current of ± 1 μA over temperature will create a 1 mV input error with a 1 kΩsource
resistance. An op amp RC active low pass filter can provide both impedance buffering and noise filtering should
a high impedance signal source be required.
OPTIONAL ADJUSTMENTS
Zero Error
The zero of the A/D does not require adjustment. If the minimum analog input voltage value, VIN(MIN), is not
ground, a zero offset can be done. The converter can be made to output 0000 0000 digital code for this minimum
input voltage by biasing any VIN (−) input at this VIN(MIN) value. This is useful for either differential or pseudo-
differential modes of input channel configuration.
The zero error of the A/D converter relates to the location of the first riser of the transfer function and can be
measured by grounding the V−input and applying a small magnitude positive voltage to the V+input. Zero error
is the difference between actual DC input voltage which is necessary to just cause an output digital code
transition from 0000 0000 to 0000 0001 and the ideal ½ LSB value (½ LSB=9.8 mV for VREF=5.000 VDC).
Full-Scale
The full-scale adjustment can be made by applying a differential input voltage which is 1 ½ LSB down from the
desired analog full-scale voltage range and then adjusting the magnitude of the VREF input for a digital output
code changing from 1111 1110 to 1111 1111.
Adjusting for an Arbitrary Analog Input Voltage Range
If the analog zero voltage of the A/D is shifted away from ground (for example, to accommodate an analog input
signal which does not go to ground), this new zero reference should be properly adjusted first. A VIN (+) voltage
which equals this desired zero reference plus ½ LSB (where the LSB is calculated for the desired analog span, 1
LSB = analog span/256) is applied to selected “+” input and the zero reference voltage at the corresponding “−”
input should then be adjusted to just obtain the 00HEX to 01HEX code transition.
Figure 13. Referencing Examples - Ratiometric
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Figure 14. Referencing Examples - Absolute with a Reduced Span
The full-scale adjustment should be made [with the proper VIN (−) voltage applied] by forcing a voltage to the VIN
(+) input which is given by:
where
• VMAX = the high end of the analog input range
• VMIN = the low end (the offset zero) of the analog range. (Both are ground referenced.) (1)
The VREF (or VCC) voltage is then adjusted to provide a code change from FEHEX to FFHEX. This completes the
adjustment procedure.
For an example see the Zero-Shift and Span Adjust circuit below.
Figure 15. Zero-Shift and Span Adjust (2V ≤VIN ≤5V)
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Figure 16. Differential Voltage Input 9-Bit A/D Figure 17. Span Adjust (0V ≤VIN ≤3V)
Diodes are 1N914
DO = all 1s if VIN(+)>VIN(−)
DO = all 0s if VIN(+)<VIN(−)
Figure 18. Protecting the Input Figure 19. High Accuracy Comparators
* VIN(−)=0.15 VCC
15% of VCC≤VXDR≤85% of VCC
Figure 20. Operating with Automotive Ratiometric Transducers
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Note: DUT pin numbers in parentheses are for ADC0844, others are for ADC0848.
Figure 21. A Stand Alone Circuit
CS •WR will update the channel configuration and start a conversion.
CS •RD will read the conversion data and start a new conversion without updating the channel configuration.
Waiting for the end of this conversion is not necessary. A CS •WR can immediately follow the CS•RD .
Figure 22. Start a Conversion without Updating the Channel Configuration
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Figure 23. ADC0844—INS8039 Interface
Sample Program for ADC0844 - INS8039 Interface Converting Two Ratiometric Differential Signals
ORG 0H
0000 04 10 JMP BEGIN ;START PROGRAM AT ADDR 10
ORG 10H ;MAIN PROGRAM
0010 B9 FF BEGIN: MOV R1,#0FFH ;LOAD R1 WITH AN UNUSED ADDR
;LOCATION
0012 B8 20 MOV R0,#20H ;A/D DATA ADDRESS
0014 89 FF ORL P1,#0FFH ;SET PORT 1 OUTPUTS HIGH
0016 23 00 MOV A,00H ;LOAD THE ACC WITH A/D MUX DATA
;CH1 AND CH2 DIFFERENTIAL
0018 14 50 CALL CONV ;CALL THE CONVERSION SUBROUTINE
001A 23 02 MOV A,#02H ;LOAD THE ACC WITH A/D MUX DATA
;CH3 AND CH4 DIFFERENTIAL
001C 18 INC R0 ;INCREMENT THE A/D DATA ADDRESS
001D 14 50 CALL CONV ;CALL THE CONVERSION SUBROUTINE
;CONTINUE MAIN PROGRAM
;CONVERSION SUBROUTINE
;ENTRY:ACC-A/D MUX DATA
;EXIT:ACC-CONVERTED DATA
ORG 50H
0050 99 FE CONV: ANL P1#0FEH ;CHIP SELECT THE A/D
0052 91 MOVX @R1,A ;LOAD A/D MUX & START CONVERSION
0053 09 LOOP: IN A,P1 ;INPUT INTR STATE
0054 32 53 JB1 LOOP ;IF INTR = 1 GOTO LOOP
0056 81 MOVX A,@R1 ;IF INTR = 0 INPUT A/D DATA
0057 89 01 ORL P1,&01H ;CLEAR THE A/D CHIP SELECT
0059 A0 MOV @R0,A ;STORE THE A/D DATA
005A 83 RET ;RETURN TO MAIN PROGRAM
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Figure 24. I/O Interface to NSC800
Sample Program for ADC0848 - NSC800 Interface
0008 NCONV EQU 16
000F DEL EQU 15 ;DELAY 50 µSEC CONVERSION
001F CS EQU 1FH ;THE BOARD ADDRESS
3C00 ADDTA EQU 003CH ;START OF RAM FOR A/D
;DATA
0000' 08 09 0A 0B MUXDTA: DB 08H,09H,0AH,0BH ;MUX DATA
0004' 0C 0D 0E 0F DB 0CH,0DH,0EH,0FH
0008' 0E 1F START: LD C,CS
000A' 06 16 LD B,NCONV
000C' 21 0000' LD HL,MUXDTA
000F' 11 003C LD DE,ADDTA
0012' ED A3 STCONV: OUTI ;LOAD A/D'S MUX DATA
;AND START A CONVERSION
0014' EB EX DE,HL ;HL=RAM ADDRESS FOR THE
;A/D DATA
0015' 3E 0F LD A,DEL
0017' 3D WAIT: DEC A ;WAIT 50 µSEC FOR THE
0018' C2 0013' JP NZ,WAIT ;CONVERSION TO FINISH
001B' ED A2 INI ;STORE THE A/D'S DATA
;CONVERTED ALL INPUTS?
001D' EB EX DE,HL
001E' C2 000E' JP NZ,STCONV ;IF NOT GOTO STCONV
END
Note: This routine sequentially programs the MUX data latch in the signal-ended mode. For CH1-CH8 a
conversion is started, then a 50 μs wait for the A/D to complete a conversion and the data is stored at address
ADDTA for CH1, ADDTA + 1 for CH2, etc.
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REVISION HISTORY
Changes from Revision C (March 2013) to Revision D Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 17
18 Submit Documentation Feedback Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: ADC0844 ADC0848
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead finish/
Ball material
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
ADC0848BCV/NOPB ACTIVE PLCC FN 28 35 RoHS & Green SN Level-2A-245C-4
WEEK -40 to 85 ADC0848
BCV
ADC0848BCVX/NOPB ACTIVE PLCC FN 28 750 RoHS & Green SN Level-2A-245C-4
WEEK -40 to 85 ADC0848
BCV
ADC0848CCV/NOPB ACTIVE PLCC FN 28 35 RoHS & Green SN Level-2A-245C-4
WEEK -40 to 85 ADC0848
CCV
ADC0848CCVX/NOPB ACTIVE PLCC FN 28 750 RoHS & Green SN Level-2A-245C-4
WEEK -40 to 85 ADC0848
CCV
(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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
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
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 2
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.
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PACKAGE OUTLINE
C
28X -.021.013 -0.530.33[ ]
28X -.032.026 -0.810.66[ ]
TYP
-.495.485 -12.5712.32[ ]
24X .050
[1.27]
-.438.382 -11.129.71[ ]
(.008)
[0.2]
TYP-.120.090 -3.042.29[ ]
.180 MAX
[4.57] .020 MIN
[0.51]
B
NOTE 3
-.456.450 -11.5811.43[ ]
A
NOTE 3
-.456.450 -11.5811.43[ ]
4215153/B 05/2017
4215153/B 05/2017
PLCC - 4.57 mm max heightFN0028A
PLASTIC CHIP CARRIER
NOTES:
1. All linear dimensions are in inches. Any dimensions in brackets are in millimeters. Any dimensions in parenthesis are for reference only.
Controlling dimensions are in inches. Dimensioning and tolerancing per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. Dimension does not include mold protrusion. Maximum allowable mold protrusion .01 in [0.25 mm] per side.
4. Reference JEDEC registration MS-018.
PIN 1 ID
(OPTIONAL)
128
4
12 18
19
25
5
11
.004 [0.1] C
.007 [0.18] C A B
SEATING PLANE
SCALE 1.000
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EXAMPLE BOARD LAYOUT
.002 MAX
[0.05]
ALL AROUND
.002 MIN
[0.05]
ALL AROUND
28X (.094)
[2.4]
28X (.026 )
[0.65]
24X (.050 )
[1.27]
(.429 )
[10.9]
(.429 )
[10.9]
(R.002 ) TYP
[0.05]
4215153/B 05/2017
4215153/B 05/2017
PLCC - 4.57 mm max heightFN0028A
PLASTIC CHIP CARRIER
NOTES: (continued)
5. Publication IPC-7351 may have alternate designs.
6. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:6X
SYMM
SYMM
128
4
12 18
19
25
5
11
METAL SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
(PREFERRED) SOLDER MASK DETAILS
EXPOSED METAL
SOLDER MASK
OPENING METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
EXPOSED METAL
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EXAMPLE STENCIL DESIGN
28X (.026 )
[0.65]
28X (.094)
[2.4]
(.429 )
[10.9]
(.429 )
[10.9]
24X (.050 )
[1.27]
(R.002 ) TYP
[0.05]
PLCC - 4.57 mm max heightFN0028A
PLASTIC CHIP CARRIER
4215153/B 05/2017
PLCC - 4.57 mm max heightFN0028A
PLASTIC CHIP CARRIER
NOTES: (continued)
7. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
8. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE:6X
SYMM
SYMM
128
4
12 18
19
25
5
11
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