PCB Tech - Red, black, green... the color of the PCB board is exquisite

Get a PCB board, the most intuitively displayed before our eyes is its color. Common PCB board colors are green, black, blue, red, yellow, etc. What are the special features of PCB boards of different colors?

Green PCB

Green PCB is currently the most common and cheapest on the market. why? The main reasons are as follows:

1. Green is less irritating to the eyes. Since childhood, the teacher told us that green is good for the eyes, protects the eyes, and resists fatigue. The production and maintenance personnel are not prone to eye fatigue when staring at the PCB board for a long time, and it is less harmful to the eyes.

2. Lower cost. Since green is the mainstream in the production process, the purchase of natural green paint will be larger, and the purchase cost of green paint will be lower than other colors. At the same time, using the same color paint in mass production can also reduce the replacement cost.

3. When the board is soldered in SMT, it needs to go through tinning, post filming and final AOI verification. These processes all need to be optically positioned and calibrated. The green background color is better for the recognition of the instrument.

02

Black PCB

Some people think that black PCB boards represent high-end, but in fact this perception is incorrect. The reason why "color represents high-end or low-end" is because manufacturers like to use black PCBs to make high-end products, and red, blue, green, and yellow to make low-end products.

In addition, the black PCB, because its surface traces are almost completely covered, cause great difficulty in later repairs, so it is a color that is not convenient to manufacture and use, and the black PCB is the most difficult for holes, so it is a good product The rate is relatively lower than that of other color PCB boards, so the price of black is relatively more expensive.

03

Red PCB

04

Blue PCB

The difference between PCBs of different colors is the color of the solder mask that is applied at the end. If the PCB design and manufacturing process are exactly the same, the color will not have any effect on performance, nor will it have any effect on heat dissipation.

PCB board solder mask

Printed circuit board (PCB) usually consists of pads, vias, solder mask, silk screen, copper wires, various components and other parts. Among them, the solder mask (solder mask) refers to the part of the printed circuit board to be painted with green oil. Through the previous introduction, we already know that solder mask ink is not only green, but also red, yellow, blue, purple, black, etc., but green is the most common.

The role of solder mask:

(1) Prevent physical disconnection of conductor circuits;

(2) In the welding process, prevent short circuit caused by bridging;

(3) Only solder the parts that must be soldered to avoid waste of solder;

(4) Reduce copper pollution to the soldering trough;

(5) Prevent insulation deterioration and corrosion caused by external environmental factors such as dust and moisture;

(6) With high insulation, it is possible to increase the density of the circuit.