Concept of Passive Components
Definition: Passive components are electronic components that do not produce energy but can store or dissipate it. They are essential in electronic circuits for controlling voltage and current.
1. Resistors
- Function: Resistors limit the flow of electric current in a circuit. They convert electrical energy into heat.
- Unit of Measurement: Ohm (Ω)
- Types:
- Fixed Resistors: Have a constant resistance value (e.g., carbon, metal film).
- Variable Resistors (Potentiometers): Allow adjustment of resistance (e.g., volume controls).
- Ohm's Law: V = I × R, where V is voltage, I is current, and R is resistance.
- Applications: Used in voltage dividers, current limiting, and biasing circuits.
2. Capacitors
- Function: Capacitors store electrical energy in an electric field and release it when needed. They can smooth out voltage fluctuations.
- Unit of Measurement: Farad (F), commonly expressed in microfarads (µF) or picofarads (pF).
- Types:
- Ceramic Capacitors: Commonly used for high-frequency applications.
- Electrolytic Capacitors: Used for larger capacitance values, polarized.
- Tantalum Capacitors: Stable and reliable, used in critical applications.
- Capacitance Formula: C = Q/V, where C is capacitance, Q is charge, and V is voltage.
- Applications: Used in filtering, timing circuits, and energy storage.
3. Inductors
- Function: Inductors store energy in a magnetic field when electrical current flows through them. They resist changes in current.
- Unit of Measurement: Henry (H)
- Types:
- Air Core Inductors: No magnetic core, used in high-frequency applications.
- Iron Core Inductors: Have a magnetic core, used for higher inductance values.
- Toroidal Inductors: Ring-shaped, efficient for reducing electromagnetic interference.
- Inductance Formula: L = N × (Φ/I), where L is inductance, N is the number of turns, Φ is magnetic flux, and I is current.
- Applications: Used in filters, transformers, and energy storage in power supplies.
