LX1973A Datasheet, PDF (1/10 Pages) Microsemi Corporation – Automotive Light Sensor

LX1973A
TM
®
Automotive Light Sensor
PRODUCTION DATA SHEET
DESCRIPTION
The LX1973A is a wide dynamic The LX1973A internal circuitry
range light sensor with a very low consists of a diode array with
dark current that is optimized for Microsemi’s Best Eye™ processing that
sensing low level light signals that provides a nearly perfect photopic light
typically occur under dark or wavelength response curve. The sensor
darkening outdoor ambient lighting. output feeds into a wide dynamic range
The LX1973A has been optimized for compression amplifier that provides
automotive systems such as headlamp accurate resolution over five decades of
brightness control or rear view mirror ambient light. The integrated dark
contrast control. Its radical (fractional current cancellation circuit facilitates
exponent) response when interfaced accurate sensing of light below 0.01
with an 8 bit DAC can detect levels lux. The current source output of the
down to 0.001 lux or levels as high as LX1973A can be gain scaled using one
500 lux.
external resistor.
The spectral response of the The LX1973A is internally trimmed
integrated light sensor closely to an initial accuracy of 5% at room
emulates the human eye so it ignores temperature and a light level of 10lux.
light such as infrared which emits Accuracy of 10% is maintained over the
energy but doesn’t aid vision. This full temperature range (-40 to +85°C).
eliminates the need for an Infrared
filter required with competitor’s light
sensors.
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
Protected By US Patents: 6,787,757; Patents Pending
KEY FEATURES
ƒ Nearly Perfect Best Eye™
Human Eye Spectral Response
ƒ 25C Dark Current <0.005 lux
ƒ 5 Decades Compressed Output
ƒ 10% Accuracy Over
Temperature
ƒ Scalable Output Voltage
ƒ No Optical Filters Needed
APPLICATIONS
ƒ Auto headlamp control
ƒ Auto mirror contrast control
5V
LXP1a97rt3A
PRODUCT HIGHLIGHT
LX1973A Response
4.0
3.0
V_OUT
R_LOAD
2.0
1.0
0.0
0.001 0.01
0.1
1
10
100
Ambient Light (in lux)
T_A (°C) DR
-40 to 85
PACKAGE ORDER INFO
Plastic MSOP Reversed Form
Plastic MSOP
8-Pin
DU _8-pin
RoHS Compliant / Pb-free
RoHS Compliant / Pb-free
LX1973AIDR
LX1973AIDU
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1973AIDU-TR)
Copyright © 2005
Rev. 1.1, 2006-12-15
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
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