TSL238T Datasheet, PDF (1/12 Pages) TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS – HIGH-SENSITIVITY LIGHT-TO-FREQUENCY CONVERTER

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D High-Resolution Conversion of Light
Intensity to Frequency With No External
Components
D High Irradiance Responsivity . . .
3.4 kHz/(mW/cm²) at λ_p = 640 nm
D Low Dark Frequency . . . < 6 Hz at 505 C
D Single-Supply Operation . . . 2.7 V to 5.5 V
D Stable 200 ppm/°C Temperature Coefficient
D Interfaces Directly to a Microcontroller
D Lead (Pb) Free Package
D RoHS Compliant
TSL238T
HIGH-SENSITIVITY
LIGHT-TO-FREQUENCY CONVERTER
TAOS080E − JUNE 2007
PACKAGE T
4-LEAD SMD
(TOP VIEW)
OE 1
4 OUT
GND 2
3 V_DD
Description
The TSL238T 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 TSL238T is characterized for operation over the temperature range of −40°C to 85°C and is supplied in
a compact 4-lead surface-mount package that is lead (Pb) free and RoHS compliant.
Functional Block Diagram
Light
Photodiode
Current-to-Frequency
Converter
Output
Available Options
DEVICE
TSL238T
T_A
−40°C to 85°C
PACKAGE − LEADS
4-lead Low Profile Surface Mount
PACKAGE DESIGNATOR ORDERING NUMBER
T
TSL238T
Terminal Functions
TERMINAL
NAME
T PKG
NO.
GND
2
OE
1
OUT
4
V_DD
3
TYPE
I
O
DESCRIPTION
Power supply ground (substrate). All voltages are referenced to GND.
Enable for f_O (active low).
Output frequency.
Supply voltage.
The LUMENOLOGY r Company
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Texas Advanced Optoelectronic Solutions Inc.
1001 Klein Road S Suite 300 S Plano, TX 75074 S (972_r) 673-0759
www.taosinc.com
Copyright E 2007, TAOS Inc.
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