The SFH 309 FA-5 with Phototransistors PHOTOTRANSISTOR manufactured by OSRAM is an opto-electronic integrated circuit (IC) that is designed to sense incident light with the use of a phototransistor. The SFH 309 FA-5 is a 4-pin device, consisting of a phototransistor connected in a circuit that includes a series resistor and a collector current amplifier. The phototransistor’s sensitivity can be adjusted by varying the current flowing through the collector current amplifier. It is encapsulated in a black-molded plastic package, and is designed to be mounted in applications where the SFH 309 FA-5 can operate at temperatures between -40 to +85 degrees Celsius. The device features a high phototransistor collector-emitter breakdown voltage of 70V VCEO, a collector-emitter saturation voltage of VCE(sat) = VF = 0.15V and a collector-emitter saturation current of ICESat = 200uA. It is also incredibly durable, boasting a dielectric strength of 500V/um and a minimum life span of 50000 hrs.