r
r
TSL237
HIGH-SENSITIVITY
LIGHT-TO-FREQUENCY CONVERTER
TAOS052G
−
SEPTEMBER 2007
D
High-Resolution Conversion of Light
D
D
D
D
D
D
Intensity to Frequency With No External
Components
High Irradiance Responsivity . . .
2.3 kHz/(mW/cm
2
) at
λ
p
= 524 nm
Low Dark Frequency . . . < 2 Hz at 505 C
Single-Supply Operation . . . 2.7 V to 5.5 V
Stable 200 ppm/°C Temperature Coefficient
Interfaces Directly to a Microcontroller
RoHS Compliant (−LF Package Only)
PACKAGE S
SIDELOOKER
(FRONT VIEW)
PACKAGE SM
SURFACE MOUNT
SIDELOOKER
(FRONT VIEW)
1
GND
2
V
DD
3
OUT
1
GND
2
V
DD
3
OUT
Description
The TSL237 light-to-frequency converter combines a silicon photodiode and a current-to-frequency converter
on a single monolithic CMOS integrated circuit. Output is a square wave (50% duty cycle) with frequency directly
proportional to light intensity (irradiance) on the photodiode. The digital output allows direct interface to a
microcontroller or other logic circuitry. The device has been temperature compensated for the
ultraviolet-to-visible light range of 320 nm to 700 nm and responds over the light range of 320 nm to 1050 nm.
The TSL237 is characterized for operation over the temperature range of
−25°C
to 70°C and is supplied in a
3-lead clear plastic side-looker package with an integral lens. When supplied in the lead (Pb) free package, the
device is RoHS compliant.
For automotive and other extended temperature applications, please contact TAOS for information.
Functional Block Diagram
Current-to-Frequency
Converter
Light
Photodiode
Output
Available Options
DEVICE
TSL237
TSL237
TSL237
T
A
−25°C
to 70°C
−25°C
to 70°C
−25°C
to 70°C
PACKAGE
−
LEADS
3-lead Sidelooker
3-lead Sidelooker — Lead (Pb) Free
3-lead Surface-Mount Sidelooker — Lead (Pb) Free
PACKAGE DESIGNATOR
S
S
SM
ORDERING NUMBER
TSL237S
TSL237S−LF
TSL237SM−LF
The
LUMENOLOGY
r
Company
Texas Advanced Optoelectronic Solutions Inc.
1001 Klein Road
S
Suite 300
S
Plano, TX 75074
S
(972) 673-0759
r
www.taosinc.com
1
r
Copyright
E
2007, TAOS Inc.
TAOS [ TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS ]
