The bipolar junction transistor
Electrical Technology · Grade 10 · about 40 minutes
How a BJT differs from a diode: two PN junctions and three terminals so a small current can control a large one.
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Other lessons in this sub-strand
- The transistor
- The bipolar junction transistor
- NPN and PNP structure
- Base, collector and emitter
- Transistor circuit symbols
- Biasing the two junctions
- Current gain (beta)
- Cut-off, active and saturation
- The transistor as a switch
- The transistor as an amplifier
- Voltage-current characteristics
- Selecting a transistor
- Testing a transistor
- Building a transistor switch
- Building a simple amplifier
- Why transistors matter