PCBA Tech - What are the electronic components on the pcba board

What are the electronic components on the PCBA board

The PCBA board refers to a finished board that is further processed on the PCB circuit board. The two are connected and independent of each other. In terms of basic electronic components, all the components on the PCB board can basically be seen on the PCBA. However, some electronic components are specially designed for PCBA processing of the power supply board, and are exclusive to the PCBA of the power supply board. So what are the electronic components on the PCBA board? Let's get to know it today.
AC power input socket AC power input socket
This is the first hurdle for AC power input from the outside. In order to block the interference from the power line and avoid the exchange noise generated by the power operation from spreading out through the power line and interfering with other electrical devices, the AC input terminal will install first to second order EMI (Electromagnetic Interference) Filter, whose function is a low-pass filter, bypasses or guides the high-frequency noise contained in the alternating current to the ground line, and only allows the wave of about 60Hz to pass.
X capacitor X capacitor (Cx, also known as cross-line filter capacitor)

This is used to bridge the capacitor between the live wire (L) and the neutral wire (N) in the composition of the EMI filter circuit. The purpose is to eliminate the low normal state noise from the power line.
Y capacitor Y capacitor (Cy, also known as line bypass capacitor)
The Y capacitor is connected across the floating ground (FG) and the live wire (L)/neutral wire (N) to eliminate high normal state and common state noise.
Common Choke Coil Common Choke Coil (cross-connected inductance)
The common mode choke coil is connected in series with the live wire (L) and the neutral wire (N) in the filter circuit to eliminate the low-pass common mode and radio frequency noise of the power line.
Fuse fuse
The fuse is when the current value flowing through it exceeds the rated limit, it will fuse to protect the connection to the back-end circuit.
Negative Temperature Coefficient Resistor Negative Temperature Coefficient Resistor (NTC)
When NTC is used, it is connected in series on the L or N line, and its internal resistance value can limit the current value at the moment of charging. The definition of negative temperature coefficient is that its resistance will decrease as its temperature rises, so as the current flows through the body, After the temperature gradually rises, its resistance will decrease accordingly to avoid unnecessary power consumption.
Metal Oxide Varistor (MOV)
The varistor is connected across the live wire and the ground wire at the back of the fuse. Its operating principle is that when the voltage difference between its two ends is lower than its rated voltage value, the body presents high impedance; when the voltage difference exceeds its rated value, the body resistance will drop rapidly. There is an approximate short-circuit state between LN. The front-end fuse will be blown by the increased current due to the short-circuit to protect the back-end circuit. Sometimes when the body bears too much power, it also self-destructs to warn the user that the device has appeared. problem.
Bridge rectifierBridge rectifier
The internal bridge rectifier composed of four diodes alternately connected, its function is to perform full-wave rectification of the input AC for use by the back-end switching circuit.
These are common electronic components on the power supply PCBA. You may be surprised that there is a hole above a small PCBA. Yes, PCBA is designed by scientific and technical personnel strictly according to the requirements. The small components on it can protect the PCB and even the entire electronic equipment. Therefore, in the design, they are indispensable.