1 low power ambient light and proximity sensor with internal ir-led and digital output ISL29044 the ISL29044 is an integrated ambient and infrared light-to-digital converter with a built-in ir led and i 2 c interface (smbus compatible). this device uses two independent adcs for concurrently measuring ambient light and proximity in parallel. the flexible interrupt scheme is designed for minimal microcontroller utilization. for ambient light sensor (als) data conversions, an adc converts photodiode current (with a light sensitivity range up to 2000 lux) in 100ms per sample . the adc rejects 50hz/60hz flicker noise caused by artificial light sources. for proximity sensor (prox) data conversions, the built-in driver turns on an internal infrared led and the proximity sensor adc converts the reflected ir intensit y to digital. this adc rejects ambient ir noise (such as sunlight) and has a 547 s conversion time. the ISL29044 provides low power operation of als and proximity sensing with a typical 133 a normal operation current (108 a for sensors and internal circuitry, ~25 a for led) with 220ma current pulses for a net 100 s, repeating every 800ms (or under). the ISL29044 uses both a hardware pin and software bits to indicate an interrupt event has occurred. an als interrupt is defined as a measurement that is outside a set window. a proximity interrupt is defined as a measurement over a threshold limit. the user may al so require that both als/prox interrupts occur at once, up to 16 times in a row before activating the interrupt pin. the ISL29044 is designed to operate from 2.25v to 3.63v over the -40c to +85c ambient temperature range. it is packaged in a clear, le ad-free 8 ld odfn package. features ? internal led + sensor = complete solution ? works under all light sources including sunlight ? dual adcs measure als/prox concurrently ?<1.0 a supply current when powered down ? temperature compensated ? pb-free (rohs compliant) intelligent and flexible interrupts ? independent als/prox interrupt thresholds ? adjustable interrupt persistency - 1/4/8/16 consecutive triggers required before interrupt applications ? display and keypad dimmin g adjustment and proximity sensing for: - mobile devices: smart phone, pda, gps - computing devices: laptop pc, netbook, tablet pc - consumer devices: lcd-tv, digital picture frame, digital camera - industrial and medical light and proximity sensing related literature ? see an1436 , ?proximity sensors? figure 1. typical application led- 5 irdr 6 led+ 4 vdd 1 int 7 sda 8 gnd 3 scl 2 i 2 c slave 0 ISL29044 scl sda i 2 c slave 1 i 2 c-diagram scl sda i 2 c slave_n i 2 c-diagram int scl sda i 2 c master controller r1 res1 r2 res1 r3 res1 c1 0.1f c2 1f c3 0.1f v_led v_pullup vdd october 30, 2012 fn8305.0 caution: these devices are sensitive to electrostatic discharge; follow proper ic handling procedures. 1-888-intersil or 1-888-468-3774 | copyright intersil americas inc. 2012. all rights reserved intersil (and design) is a trademark owned by intersil corporation or one of its subsidiaries. all other trademarks mentioned are the property of their respective owners.
ISL29044 2 intersil products are manufactured, assembled and tested utilizing iso9000 quality systems as noted in the quality certifications found at www.intersil.com/design/quality intersil products are sold by description only. intersil corporat ion reserves the right to make changes in circuit design, soft ware 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 responsi bility is assumed by intersil or its subsid iaries for its use; nor for any infringem ents of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of i ntersil or its subsidiaries. for information regarding intersil corporation and its products, see www.intersil.com fn8305.0 october 30, 2012 for additional products, see www.intersil.com/product_tree ISL29044 block diagram pin configuration ISL29044 (8 ld 2.36x3.94 (mm) optical co-package) top view vdd gnd scl ir photodiode light data 3 2 1 fosc iref irdr array als photodiode process als and ir array dual channel adcs 6 int 7 command register data register i 2 c ir driver interrupt sda 8 led+ 4 led- 5 irdr scl sda gnd int vdd 5 6 7 8 4 3 2 1 led- led+ pin descriptions pin# pin name descriptions 1 vdd voltage supply 2.25v to 3.63v. 2scli 2 c clock line can be pulled from 1.7v to above v dd , 3.63v max. 3gndground 4led+anode of ir led 5led-cathode of ir led 6 irdr ir-led driver pin - current flows into ISL29044 from led cathode. 7int interrupt pin; logic output (open-drain) for interrupt. 8sdai 2 c data line can be pulled from 1.7v to above v dd , 3.63v max.
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