An overview of the fundamental concepts of electronics, including basic components, circuits, and principles of electricity.
Introduction to Electronics – Study Notes
| Concept | Symbol / Unit | Brief Explanation |
|---|---|---|
| Voltage (V) | (V) – volts | Electrical potential difference; “pressure” that pushes charge. |
| Current (I) | (I) – amperes (A) | Flow of charge per unit time. |
| Resistance (R) | (R) – ohms (Ω) | Opposition to current flow. |
| Power (P) | (P) – watts (W) | Rate of energy conversion, (P = VI = I^{2}R = V^{2}/R). |
| Capacitance (C) | (C) – farads (F) | Ability to store charge; (Q = CV). |
| Inductance (L) | (L) – henries (H) | Ability to store magnetic energy; (V = L \frac{dI}{dt}). |
| Semiconductor | – | Material whose conductivity lies between conductors and insulators; basis for diodes, transistors, ICs. |
| Component | Symbol | Function | Typical Use |
|---|---|---|---|
| Resistor | (R) | Limits current, creates voltage drops | Biasing, voltage dividers |
| Capacitor | (C) | Stores energy, filters, couples AC | Decoupling, timing circuits |
| Inductor | (L) | Stores magnetic energy, opposes current change | Filters, transformers |
| Diode | (D) | Allows current in one direction | Rectification, protection |
| Transistor (BJT) | (Q) | Current/voltage controlled switch or amplifier | Amplifiers, switches |
| MOSFET | (M) | Voltage‑controlled switch | Power switching, digital logic |
| Integrated Circuit (IC) | – | Multiple components in one package | Microcontrollers, op‑amps, logic gates |
| Switch | – | Manually opens/closes a circuit | User input, power control |
| LED | – | Light‑emitting diode | Indicators, displays |
[ V_{out}=V_{in}\frac{R_2}{R_1+R_2} ]