A designer who uses a phototransistor to convert a modulated optical signal to an electrical signal frequently encounters problems when high-intensity background light saturates the phototransistor.

This applications note presents some basic facts about phototransistors including its different architectures commonly used in the industry. It discusses its operation and how things work inside these ...

This article is part of the Ideas for Design Series: Vol. 3, No. 8. This circuit builds on a previous idea in which the addition of an optocoupler to a microcontroller output converted a “dumb” ...