SI1120 Datasheet, PDF (1/20 Pages) Silicon Laboratories – PROXIMITY/AMBIENT LIGHT SENSOR WITH PWM OUTPUT

Si1120
PROXIMITY/AMBIENT LIGHT SENSOR WITH PWM OUTPUT
Features
 Typically 50 cm meter proximity  High EMI immunity without
range with single pulse
shielded packaging
 Seven precision optical
 Power supply: 2.2–3.7 V
measurement modes:
 Operating temperature range:
3 proximity ranges
–40 to +85 °C
3 dc ambient ranges
 Typical 10 µA current
1 calibration mode
consumption
 Low-noise ambient cancelling _{ Programmable 400/50 mA LED}
circuit allows maximum
constant current driver output
sensitivity with 8–12 bit resolution_{ Allows independent LED supply}
 ALS works in direct sunlight
voltage
(100 klux)
 Small outline 3 x 3 mm (ODFN)
 Minimum reflectance sensitivity
<1 µW/cm²
Applications
 Handsets
 Touchless switches
 Occupancy sensors
 Consumer electronics
 Notebooks/PCs
 Industrial automation
 Display backlighting control
 Photo-interrupter
Pin Assignments
PRX
TXGD
TXO
STX
Si1120
ODFN
1
8
2
7
3
6
4
5
VSS
MD
SC
VDD
U.S. Patent #5,864,591
U.S. Patent #6,198,118
Other patents pending
Description
The Si1120 is a low-power, reflectance-based proximity and ambient light
sensor with advanced analog signal processing and analog PWM output.
It includes an integrated differential photodiode, signal processor, and
LED driver. Proximity sensing is based on the measurement of reflected
light from an external, optically-isolated, strobed LED. A separate visible
light photodiode is used for ambient light sensing. The standard package
for the Si1120 is an 8-pin ODFN.
Rev. 1.0 8/10
Copyright © 2010 by Silicon Laboratories
Si1120