SI1141 Datasheet, PDF (1/66 Pages) Silicon Laboratories – PROXIMITY/AMBIENT LIGHT SENSOR IC WITH I2C INTERFACE

Si1141/42/43
PROXIMITY/AMBIENT LIGHT SENSOR IC WITH I²C INTERFACE
Features
 QuickSense™ integrated infrared
Accurate lux measurements
proximity detector
possible with IR correction
Proximity detection adjustable from
algorithm
under 1 cm to over 1 m
25.6 µs measurement cycle keeps
Three independent LED drivers
total power consumption duty cycle
15 current settings from 5.6 mA to
low without compromising
360 mA for each LED driver
performance or noise immunity
25.6 µs LED driver pulse width  Industry's lowest power consumption
500 mm proximity range with single 1.8 to 3.6 V supply voltage
pulse (<2.5 klx)
9 µA average current (LED pulsed
150 mm proximity range with single
25.6 µs every 800 ms at 180 mA
pulse (>2.5 klx)
plus 3 µA Si114x supply)
Operates at up to 128 klx (direct
< 500 nA standby current
sunlight)
Internal and external wake support
Minimum reflectance sensitivity
Built-in voltage supply monitor and
< 1 µW/cm²
power-on reset controller
High EMI immunity without shielded ^{ Serial communications}
packaging
Up to 3.4 Mbps data rate
 QuickSense™ integrated ambient
Slave mode hardware address
light sensor
decoding
10 mlx resolution possible, allowing ^{ Small-outline 10-lead 2x2 mm QFN}
operation under dark glass
 Temperature Range
1 to 128 klx dynamic range possible ^{–40 to +85 °C}
across two ADC range settings
17-bit resolution
Applications
 Handsets
 E-book readers
 Notebooks/Netbooks
 Portable consumer electronics
 Audio products
 Security panels
 Tamper detection circuits
 Dispensers
Description
 Valve controls
 Smoke detectors
 Touchless switches
 Touchless sliders
 Occupancy sensors
 Consumer electronics
 Industrial automation
 Display backlighting control
 Photo-interrupters
The Si1141/42/43 is a low-power, reflectance-based, infrared proximity and ambient
light sensor with I²C digital interface and programmable-event interrupt output. This
touchless sensor IC includes an analog-to-digital converter, integrated high-
sensitivity visible and infrared photodiodes, digital signal processor, and one, two, or
three integrated infrared LED drivers with fifteen selectable drive levels. The Si1141/
42/43 offers excellent performance under a wide dynamic range and a variety of light
sources including direct sunlight. The Si1141/42/43 can also work under dark glass
covers. The photodiode response and associated digital conversion circuitry provide
excellent immunity to artificial light flicker noise and natural light flutter noise. With
two or more LEDs, the Si1142/43 is capable of supporting multiple-axis proximity
motion detection. The Si1141/42/43 devices are provided in a 10-lead 2x2 mm QFN
package and are capable of operation from 1.8 to 3.6 V over the –40 to +85 °C
temperature range.
Pin Assignments
SDA
SCL
V_DD
INT
DNC
10
1
9
2
8
QFN-10
3
7
4
6
5
NC
LED1
GND
LED3
LED2
Preliminary Rev. 0.5 1/11
Copyright © 2011 by Silicon Laboratories
Si1141/42/43
This information applies to a product under development. Its characteristics and specifications are subject to change without notice.