INTENSITY LIGHT MEASUREMENT METER

The sensor in this circuit is a TSL35 made by Texas Instruments, its wavelenght is 750nm. Beware
that this sensor is extremely sensitive and a high intensity light will saturate the reception and will
result in wrong readings.
As you see this circuit is very simple, U4(TSL35) gives an output frequency which is proportional
to the intensity of light. We use a microcontroller to read the incoming signal, which is counted
every 1 second. To read the results we use an LCD display (LM16155), use P1 potentiometer
to provide the correct resolution. The oscillator for the microcontroller uses a quartz crystal
at 12MHz.
The entire design has a 20mA consumption with a 9 volt input source, a 9V battery will
suffice. To program the microcontroller use the following table:

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