Photosensor circuit having a level shifting circuit for biasing a first node with an operation voltage signal and a phototransistor for modulating the level of the operation voltage signal

摘要

A photosensor circuit including a first node, a level shifting circuit, a phototransistor and an inverter is provided. The first node has an operation voltage signal. The level shifting circuit is coupled to the first node for biasing the first node, so that the operation voltage signal is biased to an operation biasing level. The phototransistor is coupled to the first node for receiving an optical signal and accordingly generates a first electrical signal by means of controlling the level of the operation voltage signal. The inverter receives the first electrical signal and accordingly generates and outputs a second electrical signal, which indicates the intensity of the optical signal.