The method of rational layout of components in PCB design

First, beauty should not only consider the orderly placement of components, but also consider the beautiful flow of the line.

Because the general layman sometimes more emphasis on the former, in order to one-sided evaluation of the advantages and disadvantages of circuit design, in order to the image of the product, the former should be given priority when the performance requirements are not harsh. However, in high-performance occasions, if you have to use dual panels, but also packaged in the inside, usually can not see, you should prioritize the beauty of the line.

Second, the force circuit board should be able to withstand various external forces and vibrations during installation and work.

Therefore, the circuit board should have a reasonable shape, and the positions of various holes (screw holes, special-shaped holes) on the board should be reasonably arranged. Generally, the distance between the hole and the edge of the plate should be at least greater than the diameter of the hole. At the same time, it should also be noted that the weakest section of the plate caused by the special-shaped hole should also have sufficient bending strength. In particular, the connectors that directly "extend" out of the equipment housing on the board should be reasonably fixed to ensure long-term reliability.

For high-power, serious heating devices, in addition to ensuring heat dissipation conditions, but also pay attention to placing in the appropriate position.

Especially in sophisticated analog systems, special attention should be paid to the adverse effects of the temperature field generated by these devices on the fragile pre-amplifier circuit. Generally, the part with very large power should be made into a module separately, and certain thermal isolation measures should be taken between the signal processing circuit.

Fourth, signal interference is the most important factor to consider in PCB layout design.

The most basic aspects are: the weak signal circuit and the strong signal circuit are separated or even isolated; The AC part is separated from the DC part; The high frequency part is separated from the low frequency part; Note the direction of the signal line; Layout of ground wire; Appropriate shielding, filtering and other measures. All these have been repeatedly emphasized in a large number of discussions, and will not be repeated here.

Installation refers to a series of basic requirements put forward in the specific application in order to smoothly install the circuit board into the chassis, shell, and slot, without space interference, short circuit and other accidents, and make the specified connector in the designated position on the chassis or shell.

China's mechanical equipment PCB copying board is facing an upgrade war

There are not a few countries in the world with aircraft manufacturing capabilities, but there are only a few countries that can produce the core of the aircraft, that is, engines and fire control systems, such as the United States General Electric, Pratt & Whitney Heavy Industries and Britain's Rolls-Royce. China's so-called "self-developed" J10 fighter engine is actually provided by the SALYUT engine company under the Russian Sukhoi Design Bureau, and the fire control part is directly provided by Sukhoi. China's mechanical equipment PCB copying board is facing an upgrade war

In the military field, although China can imitate manufacturing, but master only the high imitation of its design, China does not fully grasp the core technology of key components, still often subject to others. Therefore, we should open up a new fast way out, in addition to independent research and development, the use of PCB copying technology to grasp the essence of the product and achieve the localization of key components, is a good way to catch up with the United States.

Some people may wonder: Why PCB copying technology has such a great charm? Isn't it also a cloning technique? This is true, but PCB copying is different from simple imitation, it can not only see the essence through the surface, but also transform technology into re-innovation services. It is understood that through the reverse analysis of existing electronic products or circuit boards, the schematic diagram can be reversed, the BOM list and PCB files can be made, and even the chip on the board can be decrypted, and the entire principle of product production can be understood from macro to micro, so that the entire prototype can be copied and cloned or the secondary development of hardware and software.

In the field of mechanical and electronic manufacturing, PCB copying technology has also occupied a very important position in China. In the past, China competed for the low-end market with PCB copying board technology, and got rid of the dependence of Chinese manufacturing on foreign machinery and equipment, thus enhancing the status of Chinese manufacturing. In the future, China's mechanical equipment PCB copying board will have another upgrade war. As a sensitive indicator of export and manufacturing in the middle reaches of the industrial chain, medium and high-end manufacturing is still another development force that Chinese enterprises are expected to rise after Germany and Japan.

According to the data show that with the help of PCB copying board, China's mid-end machinery manufacturing field has gradually caught up, China's machinery products are more than 20% cheaper than Germany, after the traditional foundry enterprises transferred to Southeast Asia, the required low-end machinery and equipment China has a great advantage. Taking India as an example, according to the statistics of the American Gardner Publishing Company, in 2011 India is the world's 7th largest machine tool consumer, its machine tool industry ranks 16th in the world, and its dependence on imported machine tools reaches 77%. According to the Indian Auto Parts Association, by 2018, the Indian auto, motorcycle and parts industry will need at least $1.5 billion per year to purchase production equipment. Due to the lack of a complete supporting industrial chain, as well as precision components, India will also import a large number of machinery to respond to the needs of machinery and manufacturing enterprises, which is a big opportunity for China's machinery and equipment PCB copying board upgrade and super Europe catch the United States.

Chinese PCB board enterprises should seize this rare opportunity, work closely with private enterprises and scientific research institutes, gather innovative strength, and develop the second time at a high starting point, I believe that the United States is no longer a dream!