Question

What is the application of bipolar junction transistor?

Answer 1

A **Bipolar Junction Transistor (BJT)** is a widely used electronic component in many circuits. It has **two main applications**:

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### **1. Amplification**
- **Purpose**: To make a weak signal stronger.
- **How**: A small input current at the base controls a much larger current between the collector and emitter.
- **Example**: In microphones, audio amplifiers, and radio signals.

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### **2. Switching**
- **Purpose**: To turn electronic signals or devices ON or OFF.
- **How**: By applying a small current at the base, the transistor allows a large current to flow from collector to emitter (ON). Without base current, it blocks the current (OFF).
- **Example**: In power control circuits, LED blinkers, motor drivers, and digital logic circuits.

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### Other Applications:
- **Oscillators** – to generate waveforms (like sine or square waves).
- **Signal Modulation** – in communication systems.
- **Voltage Regulation** – in power supply circuits.
- **Inverters and UPS** – for power conversion.

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Would you like a simple circuit example showing BJT as a switch or amplifier?