Transistors

Transistors: Amplify and Switch Signals

Function

• Amplification: Strengthen weak electrical signals.
• Switching: Control current flow in circuits.

Types

• BJTs (Bipolar Junction Transistors):
  • NPN or PNP with emitter, base, and collector terminals.
  • Used in amplification.
• FETs (Field-Effect Transistors):
  • Includes MOSFETs and JFETs with gate, drain, and source terminals.
  • Efficient for switching and amplification.

Key Specifications

• Current Gain (hFE): Output-to-input current ratio.
• Saturation Voltage (Vce(sat)): Voltage drop when fully on.
• Threshold Voltage (Vth): Voltage where FET starts conducting.

Applications

• Amplifiers: Audio equipment, radios.
• Switches: Digital circuits, microprocessors.
• Oscillators: Generate periodic signals for clocks and radios.

Transistors are essential for modern electronics, enabling compact, efficient, and reliable circuits.