DATASHEET
ISL29021 FN6732
Rev 0.00
March 3, 2009 Digital Proximity Sensor with Interrupt Function
The ISL29021 is an integrated proximity and infrared sensor
with a built-in IR LED driver and I2C Interface (SMBus
Compatible). This device provides infrared sensing to allow
proximity estimation featured with interrupt function.
For infrared and proximity sensing, an internal ADC has
been designed based on the charge-balancing A/D
conversion technique.
The ADC is used to digitize the output signal from the
photodiode array when the internal IR LED driver is turned
on and off for the programmed time periods under
user-selected modulation frequency to drive the external IR
LED. As this proximity sensor employs a noise cancellation
scheme to highly reject unwanted IR noise, the digital output
of proximity sensing decreases with distance. The driver
output current is user selectable up to 100mA to drive
different types of IR emitters LEDs.
Four different modes of operation can be selected via the I2C
interface: programmable IR sensing once, programmable
proximity sensing once, programmable continuous IR sensing …