PHOTOTRANSISTOR

摘要

PHOTOTRANSISTOR A phototransistor is operated with a floating base but with the transistor operating point defined by prebiasing the base, typically by injecting the base current through a prebias emitter in the collector region outside of the depletion layer. The phototransistor has a signal to noise ratio comparable to those of optimized avalanche photodiodes but operates at a significantly lower voltage and without need for temperature compensation. The phototransistor is especially well-suited for optical communications at high data rates.