LX1973B
PRODUCTION DATA SHEET
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
WWW.Microsemi .COM
Automotive Light Sensor
TM
®
Copyright © 2007
Rev. 1.3, 2008-01-11
L
L
X
X
1
1
9
9
7
7
3
3
B
B
APPLICATIONS
GENERAL DESCRIPTION
The LX1973B produces an output current that is sensitive to the level of ambient light that falls onto the photosensitive
area of the IC package. The sensitivity is amplified and compressed to provide ratio metric accuracy across several
decades. The sensitivity function is:
()
[]
0.25
EE
0.25
Lux1
I
PI
AMBIENTDARK
ref
OUT
+×=
1 Lux
0.25
= 1
0.25
I
ref
= 126µA for the Domed Top Package
I
ref
= 124µA for the Domed Bottom Package
E
DARK
= dark current equivalent Lux expressed in Lux from a white LED point source.
E
AMBIENT
= ambient illumination expressed in Lux from a white LED point source.
