# Difference Between Active and Passive Components in Electronics ## 🔋 Active Components Active components are electronic devices that **can amplify signals**, **control current**, or **produce energy**. They require an external power source to function. ### Examples: - **Transistors** – Amplify or switch electronic signals - **Diodes** (including LEDs) – Allow current in one direction, used in rectification - **Integrated Circuits (ICs)** – Contain multiple active and passive components ### Key Features: - Require external power to operate - Can **inject power** into a circuit - Can **control the flow** of electricity - Used for **amplification**, **signal processing**, and **switching** --- ## 🔌 Passive Components Passive components cannot amplify or generate power. They only **respond to** the electrical signals applied to them. ### Examples: - **Resistors** – Limit current flow - **Capacitors** – Store and release energy as an electric field - **Inductors** – Store energy in a magnetic field - **Transformers** – Transfer energy between circuits via magnetic fields ### Key Features: - Do **not require** external power to operate - **Cannot amplify** signals - Used for **filtering**, **energy storage**, **tuning**, and **impedance matching** --- ## ⚖️ Quick Analogy - **Passive Component**: Like a **valve or container** — it regulates or stores energy. - **Active Component**: Like a **pump** — it can **add energy** and control the system dynamically. --- # 🔋 10 Active Electronic Components ![Active Components](./active_components_symbols.png) # 🔌 10 Passive Electronic Components ![Passive Components](./passive_components_symbols.png) ------ # 🔌 N-Channel MOSFET: Overview An **N-channel MOSFET** (Metal-Oxide-Semiconductor Field-Effect Transistor) is a type of transistor that controls current flow using an electric field — it's a three-terminal device with: - **Gate (G)** — controls the transistor - **Drain (D)** — where current flows **into** - **Source (S)** — where current flows **out of** When a positive voltage is applied to the **gate** relative to the **source**, the MOSFET turns **on**, allowing current to flow from **drain to source** (D → S). ## ⚙️ Common Uses - Power switching in motor drivers - Voltage regulation - Signal modulation - Digital logic switching --- # 🔁 Use in an H-Bridge Motor Controller An **H-bridge** is a circuit used to control the **direction** of a DC motor. It consists of **four switches**, typically implemented with N-channel MOSFETs: ## H-Bridge Configuration: ![H-Bridge Circuit](./n_channel_h-bridge_motorcontrol.png) - **Q1 + Q4 ON** → motor spins in one direction - **Q2 + Q3 ON** → motor spins in the opposite direction - **PWM control** on low-side N-MOSFETs allows speed control Because N-channel MOSFETs conduct easily when their **gate voltage is higher than the source**, they're ideal for **low-side switching**. High-side use may require **gate driver circuits** to boost voltage. ---