1 Answer
A Bipolar Junction Transistor (BJT) has two main functions:
1. **Amplification**: The BJT can amplify weak electrical signals. When a small input current flows through the base, it controls a much larger current between the collector and emitter. This is how BJTs are used in amplifiers—taking small signals and making them larger.
2. **Switching**: A BJT can act as a switch, either allowing current to flow (in "on" state) or blocking it (in "off" state). When a sufficient base current is applied, the BJT is "on," allowing current to flow between the collector and emitter. When the base current is zero, the BJT is "off," and no current flows.
In short:
- **Amplification**: It can increase the strength of a signal.
- **Switching**: It can turn a current on or off.
1. **Amplification**: The BJT can amplify weak electrical signals. When a small input current flows through the base, it controls a much larger current between the collector and emitter. This is how BJTs are used in amplifiers—taking small signals and making them larger.
2. **Switching**: A BJT can act as a switch, either allowing current to flow (in "on" state) or blocking it (in "off" state). When a sufficient base current is applied, the BJT is "on," allowing current to flow between the collector and emitter. When the base current is zero, the BJT is "off," and no current flows.
In short:
- **Amplification**: It can increase the strength of a signal.
- **Switching**: It can turn a current on or off.