LX1972 Mini Evaluation Board
1/27/2005
Microsemi
Rev 1.1a Integrated Products
11861 Western Avenue, Garden Grove CA. 9284 1 714-898-8121 , FAX: 714-893-25 70
WWW.Microsemi .COM
LX1972 Light Sensor
TM ®
SCHEMATIC
LX1972
V
DD
VO2
4.7uF
50K C1
R1
J1
50K C2
R2
J2
1
VO1
2
4.7uF
The design of the LX1972 Mini Light Sensor Evaluation Board easily
interfaces to allow control of virtually any lighting requirement. Changing the
resistor values sets the desired minimum and maximum brightness range. As
configured, there is cons iderable g ain at lower ligh t levels (from < 1lux to about
300lux with a 5V VDD). Output voltage is ground referenced (as configured
VO2) or moving the jumper from J1 to J2 changes the voltage reference to
VDD at VO1. The J1 and J2 locations also allow placing a second resistor in
parallel to modify the light conversion gain; this will allow a wider light range
(with less overall resolution).
3V VO2lux 300 @
10mV VO2Dark Total @
: then5V VDD If
R2 IVO2
Open) J1 (if R1IVO1
5.5V to3VVDD
SRC
SNK
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Protected By U.S. Patents: 6,787,757; Patents Pending
PHOTO
PACKAGE PIN OUT
BC
P
ACKAGE
(Top View)
FUNCTIONAL PIN DESCRIPTION
N
AME
D
ESCRIPTION
V
DD
Input Supply Voltage
GND Ground Reference for Power and Sign al O utputs
1
2
VSS
VDD
L
LX
X1
19
97
72
2
