S9705_15 Datasheet, PDF (1/5 Pages) Hamamatsu Corporation – Light-to-frequency converter photo IC

Light-to-frequency converter photo IC
S9705
Converts light level to frequency of output pulse
The S9705 is a photo IC that combines a photodiode and a current-to-frequency converter on a CMOS chip. Output is a
square wave (50% duty ratio) with frequency directly proportional to light level incident on the photodiode. The CMOS level
digital output allows direct connection to a microcontroller or other logic circuitry. The S9705 has wide dynamic range and
light level can be easily measured when used with a digital counter.
Features
Converts light level to frequency
Wide dynamic range: 5 orders of magnitude
Excellent linearity
Output timing reset function
Digital output for direct interface to microcontroller
4-pin plastic package
Applications
Liquid crystal monitor backlight dimmer for mobile devices
Brightness adjustment for large-screen liquid crystal TV
Lighting dimmer
Replacement for CdS photoconductive cells
Absolute maximum ratings
Parameter
Symbol
Condition
Value
Unit
Supply voltage
Vdd Ta=25 °C
-0.3 to +6
V
Load current
Io Ta=25 °C
±2
mA
Power dissipation
Operating temperature
P Ta=25 °C
Topr
50
mW
-40 to +85
°C
Storage temperature
Tstg
Reflow soldering conditions*¹
Tsol
-40 to +100
°C
Peak temperature 250 °C max., 2 times (see page 5)
-
Note: Exceeding the absolute maximum ratings even momentarily may cause a drop in product quality. Always be sure to use the
product within the absolute maximum ratings.
*1: JEDEC level 4
www.hamamatsu.com
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