Printed circuit board, PCB for short, is the basic component of electronic components and connects the center. After disassembling the parts, many people see the dense lines on the circuit board and don’t know how to distinguish the positive and negative poles. So, the editor of the PCB manufacturer, as a professional who produces PCBs, will now help you popularize science and how to distinguish the power supply of the circuit board. Positive and negative.

First of all, pcb editor manufacturers want to tell everyone that if a designer wants to design a perfect PCB circuit board, the first thing is to determine the positive and negative poles of the circuit board. In the designer step by step design, and consider the matching issues between the individual devices. The power supply of a DC power supply circuit is generally divided into single power supply, including power supply positive and power ground; dual power supply, including power supply positive and power supply negative. The following methods can be used to distinguish the positive and negative poles in the circuit.

1. Determine the positive and negative poles according to the silk screen of the circuit board

When designing the PCB, engineers will use silkscreen to mark the pin definition of the interface part. For the positive and negative poles of the power supply, V+ and GND are generally used to distinguish the positive and negative poles of the power supply. Therefore, first of all, the silk screen on the board can learn a lot of information through the silk screen content on the board. It is very important to understand the silk screen information of the circuit board correctly. As shown in the figure below, V+ is the positive pole, and GND is the power ground.

2. Determine the positive and negative poles according to the polarity components

Polarity components are polarized and cannot be reversed when in use. Commonly used polar components include electrolytic capacitors and diodes. Therefore, the positive and negative poles of the circuit can be determined by components with polarity. Taking an electrolytic capacitor as an example, its positive electrode must be connected to the power supply positive, and its negative electrode must be connected to GND. Identifying the correct capacitor pin can also determine the positive and negative electrodes of the circuit. The capacitance determines the positive and negative poles as shown in the figure below.

3. Determine the positive and negative poles according to the large area of copper coating

In order to improve the anti-interference ability and reduce the impedance of the ground wire when designing the PCB, the ground will be electrically connected with a large area of copper. If the circuit board is copper-clad, basically GND is used as the network copper-clad. It can be judged that the large area of copper is grounded.

4. Other ways to confirm the polarity

The positive and negative poles of the chip can also be confirmed by the pins of the chip. The chip needs power supply and there are power supply pins. If you know the pin order of the chip, you can also distinguish the positive and negative poles of the power supply. It is only applicable to the situation where there is only one power supply network. If there are multiple power supply networks on the circuit board, the above methods need to be further confirmed.

Well, from the above, we can know how to distinguish the positive and negative poles of the circuit board. The current PCB market demand is increasing, and we stick to the first line. Shenzhen Honglian is a professional PCB circuit board manufacturer, with twelve years of PCB production experience, professional mass production, high-quality product services, if necessary, please contact us 400-775-2975