S i 11 4 1 / 4 2 / 4 3
P
R O X I M I T Y
/A
M BI E N T
L
I G H T
S
E N S O R
I C
WI T H
I
2
C I
N T E R F A C E
Features
Pin Assignments
QuickSense™ integrated infrared
proximity detector
Proximity detection adjustable from
under 1 cm to over 1 m
Three independent LED drivers
15 current settings from 5.6 mA to
360 mA for each LED driver
25.6 µs LED driver pulse width
500 mm proximity range with single
pulse (<2.5 klx)
150 mm proximity range with single
pulse (>2.5 klx)
Operates at up to 128 klx (direct
sunlight)
Minimum reflectance sensitivity
< 1 µW/cm
2
High EMI immunity without shielded
packaging
QuickSense™ integrated ambient
light sensor
10 mlx resolution possible, allowing
operation under dark glass
1 to 128 klx dynamic range possible
across two ADC range settings
17-bit resolution
lux measurements
possible with IR correction
algorithm
25.6 µs measurement cycle keeps
total power consumption duty cycle
low without compromising
performance or noise immunity
Industry's lowest power consumption
1.8 to 3.6 V supply voltage
9 µA average current (LED pulsed
25.6 µs every 800 ms at 180 mA
plus 3 µA Si114x supply)
< 500 nA standby current
Internal and external wake support
Built-in voltage supply monitor and
power-on reset controller
Serial communications
Up to 3.4 Mbps data rate
Slave mode hardware address
decoding
Small-outline 10-lead 2x2 mm QFN
Temperature Range
–40 to +85 °C
Accurate
DNC
SDA
SCL
V
DD
INT
1
2
3
4
10
9
8
7
6
LED1
GND
LED3
LED2
QFN-10
5
NC
Applications
Handsets
E-book readers
Notebooks/Netbooks
Portable consumer electronics
Audio products
Security panels
Tamper detection circuits
Dispensers
Valve controls
Smoke detectors
Touchless switches
Touchless sliders
Occupancy sensors
Consumer electronics
Industrial automation
Display backlighting control
Photo-interrupters
Description
The Si1141/42/43 is a low-power, reflectance-based, infrared proximity and ambient
light sensor with I
2
C 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.
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.
SILABS [ SILICON LABORATORIES ]
