Light-to-frequency converter photo IC
Converts light level to frequency of output pulse
The S9705 and S9705-01DT are photo ICs that combine 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 series has wide dy-
namic range and light level can be easily measured when used with a digital counter.
Converts light level to frequency
Wide dynamic range: 5 orders of magnitude
Output timing reset function
Digital output for direct interface to microcontroller
4-pin plastic package
Liquid crystal monitor backlight dimmer for mobile devices
Brightness adjustment for large-screen liquid crystal TV
Replacement for CdS photoconductive cells
Absolute maximum ratings
Vdd Ta=25 °C
-0.3 to +6
Io Ta=25 °C
P Ta=25 °C
Topr No dew condensation*1
-40 to +85
Tstg No dew condensation*1
-40 to +100
Reflow soldering conditions*1
Peak temperature 250 °C max, 2times(see page 7)
Peak temperature 240 °C max, 2 times
*1: W hen there is a temperature difference betw een a product and the surrounding area in high humidity environment, dew condensation
may occur on the product surface. Dew condensation on the product may cause deterioration in characteristicsand reliability.
*2: JEDEC level 4
*3: JEDEC level 5a
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.