Do you know the common component symbols on circuit boards?

Tue May 10 23:34:29 CST 2022

Do you know the common component symbols on circuit boards?


Let's learn the common component symbols of PCB together!

R - resistance

FS - Fuse

RTH - Thermistor

CY - Y Capacitors: High Voltage Ceramic Capacitors, Safety Regulations

CX - X Capacitors: High Voltage Film Capacitors, Safety Regulations

D - Diode                                                                                    

C - Capacitance                                                               

Q - transistor

ZD - Zener Diode

T - Transformer

U - IC chip

J - Jumper

VR - Adjustable Resistor

W - Zener tube

K - switch class

Y - Crystal


PCB often see numbers such as R107, C118, Q102, D202, etc. In general, the first letter identifies the component category, such as R for resistance, C for capacitance, D for diode, Q for triode, etc.; the second It is a number, indicating the function number of the circuit, such as "1" for the main board circuit, "2" for the power supply circuit, etc., which is determined by the PCB designer; the third and fourth digits indicate that the component is of the same type on the PCB board . The serial number of the component .

R117: The resistor on the motherboard, the serial number is 17.

T101: Transformer on the motherboard.

SW102: switch

LED101: Light Emitting Diode

LAMP: (indicating) light

Q104(E,B,C): Transistor, E: Emitter, B: Base, C: Collector


Do you all know the PCB component symbols? We master PCB component symbols in order to assemble PCBA or understand the circuit during maintenance, which can add strength to our electronic products!