ISL29020IROZ-T7 - Intersil Corporation

FN6505.1

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

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ISL29020

A Low Power, High Sensitivity, Light-to

Digital Sensor With I2C Interface

The ISL29020 is a low power , high sensitivity , integrated light

sensor with I2C (SMBus Compatible) interface. Its

state-of-the-art photodiode array provides close-to human

eye response and good IR rejection. This ADC is capable of

rejecting 50Hz and 60Hz flicker caused by artifi cial light

sources. The lux range select feature allows the user to

program the lux range for optimized counts/lux.

In normal operation, typical powe r consumption 55µA. In

order to further minimize power consumption, two

power-down modes have been provided. If polling is chosen

over continuous measurement of light, the auto-power-down

function shuts down the whole chip after each ADC

conversion for the measurement. The other power-down

mode is controlled by software via the I2C interface. The

power consumption can be reduced to less than 1µA when

powered down.

Designed to operate on supplies from 2.25V to 3.3V with I2C

supply from 1.7V to 3.6V, the ISL29020 is specified for

operation over the -40°C to +85°C ambient temperature range.

Block Diagram

Features

•Low Power

- 65µA Max Operating Current

- 0.5µA Max Shutdown Current

- Software Shutdown and Automatic Shutdown

• Ideal Spectral Response

- Close to Human Eye Response

- Excellent IR and UV Rejection

• Easy to Use

- Simple Output Code Directly Proportional to lux

-I

2C (SMBus Compatible) Output

- No Complex Algorithms Needed

- Variable Conversion Resolution up to 16-bits

- Adjustable Sensitivity up to 65 Counts per lux

- Works Under Various Light Sources, Including Sunlight

- Selectable Range (via I2C)

- Range 1 = 0.015 lux to 1,000 lux

- Range 2 = 0.06 lux to 4,000 lux

- Range 3 = 0.24 lux to 16,000 lux

- Range 4 = 0.96 lux to 64,000 lux

- Temperature Compensated

- Integrated 50/60Hz Noise Rejection

• Small Form Factor

- 2.0mmx2.1mmx0.7mm 6 Ld ODFN Package

• Additional Features

-I

2C and SMBus Compatible

- 1.7V to 3.6V Supply for I2C Interface

- 2.25V to 3.3V Supply

- Address Selection Pin

• Pb-Free (RoHS complia nt)

Applications

• Display and keypad dimming for:

- Mobile devices: smart phone, PDA, GPS

- Computing devices: no tebook PC, webpad

- Consumer devices: LCD-TV , digital picture frame, digital

camera

• Industrial and medical light sensing

Pinout ISL29020

(6 LD ODFN)

TOP VIEW

Ordering Information

PART NUMBER

(Note) PACKAGE

(Pb-Free) PKG.

DWG. #

ISL29020IROZ-T7* 6 Ld ODFN L6.2x2.1

ISL29020IROZ-EVALZ Evaluation Board (Pb-free)

*Please refer to TB347 for details on reel specifications.

NOTE: These Intersil Pb-free plastic packaged products employ

special Pb-free material sets; molding compounds/die attach

materials and NiPdAu plate - e4 termination finish, which is RoHS

compliant and compatible with both SnPb and Pb-free soldering

operations. Intersil Pb-free products are MSL classified at Pb-free

peak reflow temperatures that meet or exceed the Pb-free

requirements of IPC/JEDEC J STD-020.

VDD

REXT GND

SDA

SCL

COMMAND

INTEGRATING

ADC DATA

PHOTODIODE

LIGHT

3 2

OSC

IREF

COUNTER

GAIN/RANGE

EXT

SHDN

INT TIME

ISL29020

TIMING

PROCESS

ARRAY

DATA

MODE

I2C/SMBus

VDD

GND

REXT

SDA

SCL

*EXPOSED PAD CAN BE CONNECTED TO GND OR

ELECTRICALLY ISOLATED

Data Sheet August 20, 2009

2FN6505.1

August 20, 2009

Absolute Maximum Ratings (TA = +25°C) Thermal Information

VDD Supply Voltage between VDD and GND . . . . . . . . . . . . . 3.6V

I2C Bus Pin Voltage (SCL, SDA) . . . . . . . . . . . . . . . . . -0.2V to 3.6V

I2C Bus Pin Current (SCL, SDA) . . . . . . . . . . . . . . . . . . . . . . <10mA

REXT, A0 Pin Voltage . . . . . . . . . . . . . . . . . . . . . . . . . -0.2V to VDD

ESD Rating

Human Body Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2kV

Thermal Resistance θJA (°C/W)

6 Ld ODFN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Maximum Die Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . .+90°C

Storage Temperature. . . . . . . . . . . . . . . . . . . . . . . .-40°C to +100°C

Operating Temperature . . . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C

Pb-Free Reflow Profile. . . . . . . . . . . . . . . . . . . . . . . . .see link below

http://www.intersil.com/pbfree/Pb-FreeReflow.asp

CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and

result in failures not covered by warranty.

IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typical values are for information purposes only. Unless otherwise noted, all tests

are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA

Electrical Specifications VDD = 3V, TA = +25°C, REXT = 500kΩ 1% tolerance, 16-bit ADC operation, unless otherwise specified.

PARAMETER DESCRIPTION CONDITION MIN TYP MAX UNIT

VDD Power Supply Range 2.25 3.3 V

IDD Supply Current 55 65 µA

IDD1 Supply Current when Powered Down Software disabled or auto power-down 0.01 0.5 µA

VI2CSupply Voltage Range for I2C In terface 1.7 3.6 V

fOSC Internal Oscillator Frequency 650 725 800 kHz

tint ADC Integration/Conversion Time 16-bit ADC data 90 ms

FI2CI2C Clock Rate Range 1 to 400 kHz

DATA_0 Count Output When Dark E = 0 lux, Range 1 (1k lux) 1 5 Counts

DATA_F Full Scale ADC Code 65535 Counts

ΔDATA

DATA Count Output V ariation Over Three Light

Sources: Fluorescent, Incandescent

and Sunlight

Ambient light sensing ±10 %

DATA_1 Light Count Output With LSB of

0.015 lux/count E = 300 lux, Fluorescent light (Note 1), Ambient light

sensing, Range 1 (1k lux) 15000 20000 25000 Counts

DATA_2 Light Count Output With LSB of

0.06 lux/count E = 300 lux, Fluorescent light (Note 1), Ambient light

sensing, Range 2 (4k lux) 5000 Counts

DATA_3 Light Count Output With LSB of

0.24 lux/count E = 300 lux, Fluorescent light (Note 1), Ambient light

sensing, Range 3 (16k lux) 1250 Counts

DATA_4 Light Count Output With LSB of

0.96 lux/count E = 300 lux, Fluorescent light (Note 1), Ambient light

sensing, Range 4 (64k lux) 312 Counts

DATA_IR1 Infrared Count Output E = 210 lux, Sunlight (Note 2), IR sensing, Range 1 15000 20000 25000

DATA_IR2 Infrared Count Output E = 210 lux, Sunlight (Note 2), IR sensing, Range 2 5000

DATA_IR3 Infrared Count Output E = 210 lux, Sunlight (Note 2), IR sensing, Range 3 1250

DATA_IR4 Infrared Count Output E = 210 lux, Sunlight (Note 2), IR sensing, Range 4 312

VREF Voltage of REXT Pin 0.52 V

VIL SCL and SDA Input Low Voltage 0.55 V

VIH SCL and SDA Input High Voltage 1.25 V

ISDA SDA Current Sinking Capability 4 5 mA

NOTES:

1. 550nm green LED is used in production test. The 550nm LED irradiance is calibrated to produce the same DATA count against an illuminance

level of 300 lux fluorscent light.

2. 850nm green LED is used in production test. The 850nm LED irradiance is calibrated to produce the same DA T A_IR count against an illuminance

level of 210 lux sunlight at sea level.

ISL29020

3FN6505.1

August 20, 2009

Principles of Operation

Photodiodes and ADC

The ISL29020 contains two photodi ode arrays which convert

light into current. The spectral resp onse for ambient ligh t

sensing and IR sensing is shown in Figure 8 in the “Typical

Performance Curves” on p age 9. After light is converted to

current during the light signal p rocess, the current output is

converted to digital by a single bu ilt-in 16-bit Analog-to -Digit al

Converter (ADC). An I2C co mmand reads the ambient l ight or

IR intensity in counts.

The converter is a charge-balancing integrating type 16-bit

ADC. The chosen method for conversion is best for converting

small current signals in the presence of an AC periodic noise. A

100ms integration time, for instance, highly rejects 50Hz and

60Hz power line noise simultaneously . See “Integration Time or

Conversion Time” on p age 6 and “Noise Rejection” on page 7.

The built-in ADC offers user flexibility in integration time or

conversion time. There are two timing modes: Internal Timing

Mode and External Timing Mode. In Internal T iming Mode,

integration time is determined by an internal oscillator (fOSC),

and the n-bit (n = 4, 8, 12,16) counter inside the ADC. In

External Timing Mode, integration time is determined by the

time between two consecutive I2C External Timing Mode

commands. See “External T iming Mode” on p age 6. A good

balancing act of integration time and resolution depending on

the application is required for optimal results.

The ADC has I2C programmable ranges to dynamically

accommodate various lighting conditi ons. For very dim

conditions, the ADC can be configured at its lower range

(Range 1). For bright conditions, the ADC can be configured

at its higher range (Range 2).

I2C Interface

There are three 8-bit registers available inside the ISL29020.

The command register defines the operation of the device.

The command register does not cha nge until the register is

overwritten. The two data registers are Read-Only for 16-bit

ADC output or timer output. The data registers contain the

ADC's or timer’s latest digital output.

The ISL29020’s I2C interface slave address can be selected

as 1000100 or 1000101 by connecting A0 pin to GND or

VDD, respectively. When 1000100x or 1000101x with x as R

or W is sent after the Start condition, this device compares

the first seven bits of this byte to its address and matches.

Figure 1 shows a sample one-byte read. Fi gure 2 sh ows a

sample one-byte write. Figure 3 shows a sync_I2C timing

diagram sample for external ly controlled integration ti me. The

I2C bus maste r always drives the SCL (clock) line, while either

the master or the slave can drive the SDA (data) line . Every

I2C transaction begins with the master asserting a start

condition (SDA falling whil e SCL remains high). The following

byte is driven by the master, and includes the slave address

and read/write bit. The receiving device is respo nsible for

pulling SDA low during the acknowledgement p eriod. Every

I2C transaction ends w ith the master assertin g a stop

condition (SDA rising whi le SCL remains high).

For more information about the I2C standard, please consult

the Philips® I2C specification documents.

Low-Power Operation

The ISL29020 initial opera tion is at the power-down mode

after a supply voltage is provided. The data registers contain

the default value of 0. When the ISL29020 receives an I2C

command to do a one-time measurement from an I2C

master, it will start light sensing and ADC conversion. It will

go to the power-down mode automatically after one

conversion is finishe d and keep the conversion data

available for the master to fetch anytime afterwards. The

ISL29020 will continuously do light sensing an d ADC

conversion if it receives an I2C command of continuous

measurement. It will continuously update the data registers

with the latest conversion data. It will go to the power-down

mode after it receives the I2C command of power-down.

Pin Descriptions

PIN NUMBER PIN NAME DESCRIPTION

1 VDD Positive supply; connect this pin to a 2.25V to 3.3V supply.

2 GND Ground pin.

3 REXT External resistor pin for ADC reference; connect this pin to ground through a (nominal) 500kΩ resistor.

0Bit 0 of I2C address; ground or tie this pin to VDD. No floating.

5SCLI

2C serial clock The I2C bus lines can be pulled from 1.7V to above VDD, 3.6V max.

6SDAI

2C serial data

ISL29020

4FN6505.1

August 20, 2009

FIGURE 1. I2C READ TIMING DIAGRAM SAMPLE

START WA A

A6 A5 A4 A3 A2 A1 A0 W A R7 R6 R5 R4 R3 R2 R1 R0 A A6 A5 A4 A3 A2 A1 A0 W A

A A AD7D6D5D4D3D2D1D0

1357 1357 123456 9 2 4 6

STOP START

SDA DRIVEN BY MASTER

DEVICE ADDRESS

SDA DRIVEN BY ISL29020

DATA BYTE0REGISTER ADDRESSDEVICE ADDRESSI2C DATA

SDA DRIVEN BY MASTER

2468

924689 78135789

I2C SDA IN

2C SDA OUT

C CLK

FIGURE 2. I2C WRITE TIMING DIAGRAM SAMPLE

START W A A

A6 A5 A4 A3 A2 A1 A0 W A R7 R6 R5 R4 R3 R2 R1 R0 A B7 B6 B5 B4 B3 B2 B1 B0 A

12615948

STOP

SDA DRIVEN BY MASTER

FUNCTIONSREGISTER ADDRESSDEVICE ADDRESS

SDA DRIVEN BY MASTER SDA DRIVEN BY MASTER

I2C DATA

I2C SDA IN

I2C SDA OUT

I2C CLK IN

345 789 234 678 123 567 9

FIGURE 3. I2C SYNC_I2C TIMING DIAGRAM SAMPLE

A 6 A5 A4 A3 A2 A1 A0 W AR7R6R5R4R3R2R1R0 A

15 4

START W ASTOPREGISTER ADDRESSDEVICE ADDRESS AREGISTER ADDRESSREGISTER ADDRESSI2C DATA

I2C SDA IN

I2C SDA OUT

I2C CLK IN

SDA DRIVEN BY MASTER SDA DRIVEN BY MASTER A

234 6789123 56789

ISL29020

5FN6505.1

August 20, 2009

There are three 8-bit regi sters in the ISL29020. Table 1 summarizes their functions.

Command Register (00 hex)

The Read/Write command register has five functions:

1. Enable: Bit 7. This bit enable s the ISL290 20 with logic 1

and powers down ISL29020 with logic 0.

2. Measurement Mode: Bit 6. This bit co ntrols the two

measurement modes of the device. A logic 0 puts the

device in the one-time measurement mode in which the

device is automati cally shut-down after each

measurement. A logic 1 puts the device in the continuous

measurement mode in which data is collected

continuously.

3. Light Sensing: Bit 5. This bit programs the device to do the

ambient light or the infrared (IR) light sensing. A logic 0,

requests for the ambient light sen sing and a lo gic 1

requests for the IR sensing.

4. Timing Mode and Resolution: Bits 4, 3 and 2. These three

bits determine whether the integration time is done

internally or externally , and the number of bits for ADC. In

Internal Timing Mode, integration ti me is determined by

an internal oscillator (fOSC) and the n-bit (n = 4, 8, 12, 16)

counter inside the ADC. In External Timing Mode, the

integration time is determined by the time between two

consecutive sync_I2C pulse commands.

With Bit 4 set to 0, the device is configured to run in the

Internal-T iming mode. For example, the command register

content should be 1xx000xx to request 16-bit ADC in the

internal-timing mode.

With Bit 4 set to 1, the device is configured to run in the

External-T iming mode. For the external timing, the command

1xx101xx needs to be sent to request the T imer data, the

number of clock cycles counted within the duration between

the two sync pulses (refer to Table 2). The Timer count is

read from register 01h (LSB) and 02h (MSB). The command

1xx100xx needs to be sent to request the ADC conversion.

The ADC data is also read from register 01h (LSB) and 02h

(MSB).

Bits 3 and 2 determine the number of clock cycles per

conversion in the Internal-Timing mode. Changing the

number of clock cycles does more than just change the

resolution of the device. It also changes the integration

time, which the ADC uses to sample the photodiode

current signal for a measurement.

TABLE 1. REGISTER SET

ADDR REG NAME

BIT

DEFAULT765 4 3210

00h COMMAND EN MODE LIGHT RES2 RES1 RES0 RANGE1 RANGE0 00h

01h DATALSB D7 D6 D5 D4 D3 D2 D1 D0 00h

02h DATAMSB D15 D14 D13 D12 D11 D10 D9 D8 00h

TABLE 2. WRITE ONLY REGISTERS

ADDRESS NAME FUNCTIONS/DESCRIPTION

b1xxx_xxxx sync_I2C Writing a logic 1 to this address bit

ends the current ADC-integration

and starts another. Used only with

External Timing Mode.

TABLE 3. ENABLE

BIT 7 OPERATION

0 Power-down the device

1 Enable the device

TABLE 4. MEASUREMENT MODE

BIT 6 OPERATION

0 One-time measurement

1 Continuous measurement

TABLE 5. LIGHT SENSING

BIT 5 OPERATION

0 Ambient light sensing

1 Infrared light sensing

TABLE 6. TIMING MODE AND RESOLUTION

BITS 4:3:2 MODE

0:0:0 Internal Timing, 16-bit ADC data output

0:0:1 Internal Timing, 12-bit ADC data output

0:1:0 Internal Timing, 8-bit ADC data output

0:1:1 Internal Timing, 4-bit ADC data output

1:0:0 External Timing, ADC data output

1:0:1 External Timing, Timer data output

1:1:0 Reserved

1:1:1 Reserved

ISL29020

6FN6505.1

August 20, 2009

5. Range: Bits 1 and 0. The Full Scale Range (FSR) can be

adjusted via I2C using Bits 1 and 0. Table 8 lists the

possible values of FSR for the 500kΩ REXT resistor.

Data Registers (01 hex and 02 hex)

The device has two 8-bit read-only registers to hold a 16-bit

data from ADC or Timer. The most significant byte is

accessed at 02 hex, and the least significant byte is

accessed at 01 hex. The registers are refreshed after every

conversion cycle.

Calculating Lux

The ISL29020’s ADC output codes, DATA, are directly

proportional to lux in the ambient light sensing, as shown in

Equation 1.

Here, Ecal is the calculated lux reading. The constant α is

determined by the Full Scale Range and the ADC’s

maximum output counts. The constant can also be viewed

as the sensitivity: the smallest lux measurement the device

can measure, as shown in Equation 2.

Here, Range(k) is defined in Table 8. Countmax is the

maximum output counts from the ADC.

The transfer function used for ea ch timing mode becomes:

INTERNAL TIMING MODE

Here, n = 4, 8, 12 or 16. This is the number of ADC bits

programmed in the command regi ster. 2n represents the

maximum number of counts possible from the ADC output in

Internal-T iming mode. Data is the ADC output stored in the

data registers (01 hex and 02 hex).

EXTERNAL TIMING MODE

Here, Timer sets up the ADC’s maximum count reading and

it is the number of clock cycles accrued in the integration

time (set by sync_I2C pulses) in External-Timing mode. It is

stored in the data registers 01h and 02h when the command

is coded as 1xx101xx. Data is the ADC output. In this mode,

the command has to be sent out again with code 1xx100xx

to request the ADC output data from registers 01h and 02h.

External Scaling Resistor REXT for fOSC and

Range

The ISL29020 uses an external resistor REXT to fix its

internal oscillator frequency, fOSC and the light sensing

range, Range. fOSC and Range are inversely proportional to

REXT. For user simplicity, the proportionality constant is

referenced to 500kΩ:

Integration Time or Conversion Time

Integration time is the period during which the device’s

analog-to-digital ADC converter samples the photodiode

current signal for a measurement. Integration time, in other

words, is the time to complete the conversion of analog

photodiode current into a digital signal (number of counts).

Integration time affects the measurement resolution. For

better resolution, use a longer integration time. For short and

fast conversions, use a shorter integration time.

The ISL29020 offers user flexibility in the integration time to

balance resolution, speed and noise rejection. Integration time

can be set internally or externally by programming the bit 4 of

the command register 00(hex).

INTEGRATION TIME IN INTERNAL-TIMING MODE

Most applications will use the Internal-T iming mode. In this

mode, fOSC and ADC n-bits resolution determine the

integration time, tint, as shown in Equation 7.

where n is the number of bits of resolution and n = 4, 8, 12 or

16. 2n, therefore, is the number of clock cycles. n ca n be

programmed at the command register 00(he x) bit s 3 and 2.

TABLE 7. RESOLUTION/WIDTH

BITS 3:2 NUMBER OF CLOCK CYCLES

0:0 216 = 65,536

0:1 212 = 4,096

1:0 28 = 256

1:1 24 = 16

TABLE 8. RANGE/FSR LUX

BITS

1:0 k RANGE(k) FSR (LUX) @

ALS SENSING FSR (LUX) @ IR

SENSING

0:0 1 Range1 1,000 Refer to page 2

0:1 2 Range2 4,000 Refer to page 2

1:0 3 Range3 16,000 Refer to page 2

1:1 4 Range4 64,000 Refer to page 2

TABLE 9. DATA REGISTERS

ADDRESS

(hex) CONTENTS

01 Least-significant byte of most recent ADC or T imer dat a.

02 Most-significant byte of most recent ADC or Timer data.

Ecal αDATA×=(EQ. 1)

αRange k()

Countmax

----------------------------

=(EQ. 2)

(EQ. 3)

ERange k()

--------------------------- DATA×=

(EQ. 4)

ERange k()

Timer

--------------------------- DATA×=

(EQ. 5)

Range 500kΩ

REXT

------------------ Range k()×=

(EQ. 6)

fOSC 500kΩ

REXT

------------------ 725×kHz=

tint 2n1

fOSC

--------------

×2nREXT

725kHz 500kΩ×

----------------------------------------------

×== (EQ. 7)

ISL29020

7FN6505.1

August 20, 2009

INTEGRATION TIME IN EXTERNAL TIMING MODE

The External Timing Mode is recommended when the

integration time is needed to synchronize to an external

signal, such as a PWM to eliminate noise.

The synchronization can be implemented by using I2C sync

command. The 1st I2C sync command starts the conversion.

The 2nd completes the conversion then st a rt s ove r again to

commence the next conversion. The integration time, tint, is

the time interval betwee n the two sync pulses:

where T imer is the number of internal clock cycles obtained

from dat a registers and fOSC is the internal oscillator frequency .

The internal oscillator , fOSC, operates identically in both the

internal and external timing modes. However, in External

T iming Mode, the number of cloc k cycles per integration is no

longer fixed at 2n. The number of clock cycles varies with the

chosen integration time, and is limited to 216 = 65,536. In order

to avoid erroneous readings the integration time must be short

enough not to allow an overflow in the counter register .

Noise Rejection

In general, integrating type ADCs have excellent

noise-rejection characteristics for periodic noise sources

whose frequency is an integer multiple of the conversion

rate. For instance, a 60Hz AC unwanted signal’s sum from

0ms to k*16.66ms (k = 1,2...ki) is zero. Similarly, setting the

device’s integration time to be an integer multiple of the

periodic noise signal, gre atly improves the light sensor

output signal in the presence of noise.

Optical Design

Flat Window Lens Design

A window lens will surely limit the viewing angle of the

ISL29020. The window lens should be placed directly on top

of the device. The thickness of the lens should be kept at

minimum to minimize loss of power due to reflection and

also to minimize loss due to absorption of energy in the

plastic material. A thickness of t = 1mm is recommended for

a window lens design. The bigger the diameter of the

window lens, the wider the viewing angle is of the ISL29020.

Table 11 shows the recommended dimensions of the optical

window to ensure both 35° and 45° viewing angle. These

dimensions are based on a window lens thickness of 1.0mm

and a refractive index of 1.59.

Window with Light Guide Design

If a smaller window is desired while maintaining a wide

effective viewing angle of the ISL29020, a cylindrical piece of

transparent plastic is needed to trap the light and then focus

and guide the light onto the device. Hence, the name light

guide or also known as light pipe. The pipe should be placed

directly on top of the device with a di stance of D1 = 0.5mm

to achieve peak performance. The light pipe should have

minimum of 1.5mm in diameter to ensure that whole area of

the sensor will be exposed. See Figure 5.

TABLE 10. INTEGRATION TIME OF n-BIT ADC

REXT

(kΩ) n = 16-BIT n = 12-BIT n = 8-BIT n = 4-BIT

250 50ms 3.2ms 200µs 12.5µs

500** 100ms 6.25ms 390µs 24µs

1000 200ms 12.5ms 782µs 49µs

1500 300ms 18.8ms 1.17ms 73µs

2000 400ms 25ms 1.56ms 98µs

**Recommended REXT resistor value

tint Timer

fOSC

-----------------

=(EQ. 8)

tint 65,535

fOSC

------------------

<(EQ. 9)

TABLE 1 1. RECOMMENDED DIMENSIONS FOR A FLA T

WINDOW DESIGN

DTOTAL D1 DLENS @ 35°

VIEWING ANGLE DLENS @ 45°

VIEWING ANGLE

1.5 0.50 2.25 3.75

2.0 1.00 3.00 4.75

2.5 1.50 3.75 5.75

3.0 2.00 4.30 6.75

3.5 2.50 5.00 7.75

t = 1 Thickness of lens

D1 Distance between ISL29020 and inner edge of lens

DLENS Diameter of lens

DTOTAL Distance constraint between the ISL29020 and lens

outer edge

* All dimensions are in mm.

DLENS

∅

D1 DTOTAL

∅ = VIEWING ANGLE

WINDOW LENS

ISL29020

FIGURE 4. FLAT WINDOW LENS

E = DATA

216 x 1000

ISL29020

8FN6505.1

August 20, 2009

Suggested PCB Footprint

It is important that the users check the “Surface Mount

Assembly Guidelines for Optical Dual FlatPack No Lead

(ODFN) Package” before starting ODFN product board

mounting.

http://www.intersil.com/data/tb/TB477.pdf

Layout Considerations

The ISL29020 is relatively insensitive to layout. Like other

I2C devices, it is intended to provide excellent performance

even in significantly noisy environments. There are only a

few considerations that will ensure best performance.

Route the supply and I2C traces as far as possible from all

sources of noise. Use one 0.01µF power-supply decoupling

capacitor, placed close to the device.

Typical Circuit

A typical application for the ISL2902 0 is shown in F igure 6.

The ISL29020’s I2C address is hardwired as 100 0100. The

device can be tied onto a system’s I2C bus together wi th

other I2C compliant devices.

Soldering Considerations

Convection heating is recomme nded for reflow solde ring;

direct-infrared heating is no t recommended. The plastic

ODFN package does not require a custo m reflow soldering

profile, and is qualified to +260°C. A st andard reflow soldering

profile with a +260°C maximum is recommended.

DLENS

LIGHT PIPE

ISL29020

D2 > 1.5mm

FIGURE 5. WINDOW WITH LIGHT GUIDE/PIPE

FIGURE 6. ISL29020 TYPICAL CIRCUIT

VDD

GND

REXT

SCL 5

SDA 6

ISL29020

10k

REXT

500k

0.01µF

2.25V TO 3.3V

MICROCONTROLLER

SDA

SCL

C SLAVE_0

C SLAVE_1

C SLAVE_n

C MASTER

SCL

SDA

SCL

SDA

1.7V TO 3.6V

ISL29020

9FN6505.1

August 20, 2009

Typical Performance Curves (VDD = 3V, REXT = 500kΩ)

FIGURE 7. SPECTRAL RESPONSE OF LIGHT SOURCES FIGURE 8. SPECTRAL RESPONSE FOR AMBIENT LIGHT

SENSING AND IR SENSING

FIGURE 9. RADIATION PATTERN FIGURE 10. SENSITIVITY TO THREE LIGHT SOURCES

FIGURE 11. OUTPUT CODE FOR 0 LUX vs TEMPERATURE FIGURE 12. OUTPUT CODE vs TEMPERATURE

0.2

0.4

0.6

0.8

1.0

1.2

300 400 500 600 700 800 900 1000 1100

WAVELENGTH (nm)

NORMALIZED LIGHT INTENSITY

SUN

HALOGEN

INCANDESCENT

FLUORESCENT

-0.2

0.2

0.4

0.6

0.8

1.0

1.2

300 400 500 600 700 800 900 1000 1100

WAVELENGTH (nm)

NORMALIZED RESPONSE

HUMAN EYE

IR SENSING

AMBIENT LIGHT SENSING

RADIATION PATTERN

LUMINOSITY

ANGLE

RELATIVE SENSITIVITY

90°

80°

70°

60°

50°

40°

30° 20° 10° 0° 10° 20° 30° 40°

50°

60°

70°

80°

90°

0.2 0.4 0.6 0.8 1.0

100

200

300

400

500

600

700

800

900

1000

0 100 200 300 400 500 600 700 800 900 1000

LUX METER READING (LUX)

CALCULATED ALS READING (LUX)

INCANDESCENT

HALOGEN

FLUORESCENT

ALS SENSING

RANGE 1 (1k Lux)

16-BIT ADC

ADC OUTPUT (COUNT)

32768

65535

1000 LUX

Ecal = 216 x DATA

OUTPUT CODE (COUNTS)

TEMPERATURE (°C)

-60 -20 20 60 100

0 lux

OUTPUT CODE RATIO (FROM +30°C)

TEMPERATURE (°C)

0.90

0.95

1.00

1.05

1.10

-60 -20 20 60 100

300 Lux FLUORESCENT LIGHT

ALS SENSING

RANGE 1 (1k Lux)

ISL29020

All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.

Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality

Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without

notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and

reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result

from its use. No lice nse is gran t ed by i mpli catio n or other wise u nder an y p a tent or patent right s of Int ersi l or it s sub sidi aries.

For information regarding Intersil Corporation and its products, see www.intersil.com

FN6505.1

August 20, 2009

FIGURE 13. SUPPLY CURRENT vs TEMPERATURE

Typical Performance Curves (VDD = 3V, REXT = 500kΩ) (Co ntin ued)

SUPPLY CURRENT (µA)

TEMPERATURE (°C)

-50 -25 0 25 50 75 100 125

VDD = 2.25V

2.10

2.00

SENSOR OFFSET

0.59

0.34

0.23

FIGURE 14. SENSOR LOCATION OUTLINE

ISL29020

11 FN6505.1

August 20, 2009

ISL29020

Package Outline Drawing

L6.2x2.1

6 LEAD OPTICAL DUAL FLAT NO-LEAD PLASTIC PACKAGE (ODFN)

Rev 0, 9/06

located within the zone indicated . Th e pin #1 identifier may be

Unless otherwise specified, tol erance : Decim al ± 0.05

Tiebar shown (if present) is a non-functional feature.

The configuration of the pin #1 identifier is optio nal, but must be

between 0.15mm an d 0.3 0m m from the te rminal tip.

Dimension b applies to the metallized terminal and is measured

Dimensions in ( ) for Reference Only.

Dimensioning and tolerancing conform to AMSE Y14.5m-1994 .

either a mold or mark feature.

Dimensions are in millimeters.1.

NOTES:

(4X) 0.10

INDEX AREA

PIN 1

2.10

2.00

SEATING PLANE

BASE PLANE

0.08

0.10

SEE DETAIL "X"

0 . 00 MIN .

DETAIL "X"

0 . 05 MAX.

0 . 2 REF

SIDE VIEW

TYPICAL RECOMMENDED LAND PATTERN

( 6X 0 . 30 )

( 6X 0 . 55 )

TOP VIEW

(0 . 65)

(1 . 95)

(0 . 65) (1 . 35)

BOTTOM VIEW

6X 0 . 35 ± 0 . 05 B0.10 MAC

1 . 35 1 . 30 REF

INDEX AREA

PIN 1

0.65

0 . 65

MAX 0.75

6X 0 . 30 ± 0 . 05