PC817 DIP Optocoupler

In the previous tutorial we saw that the standard Bipolar Transistor or BJT, comes in two basic forms. An NPN (Negative-Positive-Negative) type and a PNP (<b”>Positive-Negative-Positive) type.</b”>

The most commonly used transistor configuration is the NPN Transistor. We also learnt that the junctions of the bipolar transistor can be biased in one of three different ways – Common Base, Common Emitter and Common Collector.