Sometimes I wish FETs had become practical before bipolar transistors. A FET is a lot more like a tube and amplifies voltages. Bipolar transistors amplify current and that makes them a bit harder to ...

The circuit in Figure 1 sinks a constant current (ICE3) through Q3’s collector and emitter. This design is balanced so changes in Q3’s base-emitter voltage (VBE) don’t affect the current sink’s ...

The common-emitter amplifier circuit generates an output which transitions from a high state to a low state when light in the near-infrared range is detected by the phototransistor. The wavelength ...

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 ...