Circuit Board components: how to identify various PCB components

Circuit boards consist of numerous components, from resistors and capacitors to connectors and integrated circuits, each playing a vital role in the operation of electronic devices. Below is a list of commonly used PCB components, providing insight into their basic functions and how they affect the board’s overall functionality.

Resistor

Resistor

Resistors primarily control and regulate current and voltage within a circuit. By providing resistance to the current, they help distribute voltage, convert electrical energy into heat, and protect other components from excessive current damage.

Capacitor

Capacitor

Capacitors store electric charge between two plates separated by a dielectric material, air, or vacuum. They filter noise, stabilize voltage, and generate circuit resonance.

Inductor

Inductor

Inductors filter, oscillate, delay, and trap signals within circuits. They filter signals, reduce noise, stabilize current, and suppress electromagnetic interference, often pairing with capacitors to form LC filters.

Diode

Diode

Semiconductor diodes protect circuits and extend their lifespan. The development of semiconductor diodes has optimized integrated circuits, playing a significant role in many fields and maintaining proper circuit function.

Transistor

Transistor

Transistors amplify current, with small changes in base current controlling larger changes in collector current. As versatile semiconductor devices, transistors provide detection, rectification, amplification, switching, regulation, and signal modulation, supporting both digital and analog functions.

Relay

Relay

A relay is an electrically controlled device that, upon reaching a specified input change, creates a predefined step change in the controlled quantity within the output circuit. Often used in automation, it functions as an “automatic switch” by using small currents to control larger currents, providing automatic adjustment, safety protection, and circuit switching.

Potentiometer

Potentiometer

With two fixed ends on the resistive element, the potentiometer allows manual adjustment of the wiper along the resistive path to alter resistance, thereby controlling voltage and current within the circuit.

Sensor

Sensor

Sensors detect physical conditions (such as temperature or pressure) and convert them into signals.

Connector

Connector

Connectors are electrical structural components linking electronic devices and circuits, bridging disconnected or isolated circuits to ensure the smooth flow of current or signals, enabling the circuit to perform its intended function.

Power Supply

Power Supply

The power supply converts other forms of energy into electrical energy, delivering stable voltage and current to each circuit component to ensure proper device operation.

Switch

Switch

Switches control the flow of current in electronic circuits, enabling or disabling circuits through manual or automatic operations, allowing for the turning on, off, or adjustment of devices.

Electronic Transformer

Electronic Transformer

An electronic transformer converts input voltage to output a different voltage, isolating, rectifying, or modulating frequency to meet the power needs of various devices and circuits.

Integrated Circuit

Integrated Circuit

An integrated circuit (IC) is a miniature electronic device that consolidates numerous components (such as transistors, resistors, and capacitors) onto a small semiconductor chip, performing functions like amplification, filtering, logic operations, and storage. It significantly reduces device size, enhances performance and reliability, and lowers costs, standing as a core component of modern electronics.