LX1974
TM
庐
Ambient Light Detector
P
RODUCTION
D
ATA
S
HEET
DESCRIPTION
KEY FEATURES
Near Human Eye Spectral
Response
Very Low IR Sensitivity
Highly Accurate & Repeatable
Output Current vs. Light
Scalable Output Voltage
Temperature Stable
Integrated High Gain Photo
Current Amplifiers
No Optical Filters Needed
APPLICATIONS
The LX1974 is a low cost silicon
light sensor with spectral response that
closely emulates the human eye.
Patented circuitry produces peak
spectral response at 520nm, with IR
response less than 卤5%, of the peak
response, above 900nm.
The photo sensor is a PIN diode array
with a linear, accurate, and very
repeatable current transfer function.
High gain current mirrors on the chip
multiply the PIN diode photo-current
to a sensitivity level that can be
voltage scaled with a standard value
external resistor. Output current from
this simple to use two-pin device can
be used directly or converted to a
voltage by placing it in series with a
single resistor at either of its two pins.
Dynamic range is determined by the
resistors (typically in the range of 10K
to 100K) and power supply values.
Typically the LX1974 needs only 1.8V
of headroom to operate at 1000 Lux
illumination.
Internal temperature compensation
allows dark current to be kept below
200nA over the full specification
temperature range (-40 to +85掳C),
providing high accuracy at low light
levels. Usable ambient light conditions
range is from 1 to more than 5000 Lux.
The LX1974 is optimized for
controlling back lighting systems in low
cost consumer products such as LCD
TV, portable computers, and digital
cameras.
WWW .
Microsemi
.C
OM
Portable Electronic Displays
LCD TV Backlight Systems
Digital Still Cameras (DSC)
Desktop Monitors
Notebook Computers
IMPORTANT:
For the most current data, consult
MICROSEMI鈥檚
website:
http://www.microsemi.com
Protected By U.S.Patents: 6,787,757; Patents Pending
PRODUCT HIGHLIGHT
LX1974
LIGHT
LX1974
LX1974
PACKAGE ORDER INFO
T
A
(掳C)
-40 to 85
BC
Plastic 1206
2-Pin
LX1974IBC
RoHS Compliant / Pb-free
Note: Available in Tape & Reel. Append the
letters 鈥淭R鈥?to the part number.
(i.e. LX1974IBC-TR)
Copyright
漏
2005
Rev. 1.0, 2006-05-09
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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