Light-to-Frequency Converter - The TSL235 Light-to-Frequency Converter combines a silicon photodiode and a current-to-frequency converter on a single monolithic CMOS integrated circuit. The output is a square wave (50% duty cycle) with frequency directly proportional to light intensity. Because it is TTL compatible, the output allows direct interface to a microcontroller or other logic circuitry. the TSL235R is characterized for operation over the temperature range of -25 degrees C to 70 degrees C.
Light-to-Voltage Optical Sensor - The TSL254R is a precision CMOS Light-to-Voltage sensor that combines a photodiode and a transimpedance amplifier on a single monolithic IC. The feedback resistor is 1 Megohm. The output voltage is directly proportional to the light intensity(irradiance) on the photodiode. At 635nm, the irradiance responsivity is 9mV/(uW/cm2) with an output rise and fall time of 2usec.
