PCB layout is laying conductive signal path connecting the various devices, like decorate the road, connecting the city by car.
Road construction requires a return to a two-line, PCB routing the same principle, you need two lines form a loop ,for the low-frequency circuit point is a circuit; for the electromagnetic field in terms of speed it is the transmission line, the most common, such as differential signals line. Such as USB, cable, etc.
We can say that the differential signal lines, is the ideal model for connecting devices signals. The higher the signal requirements, the more you want to close the differential signal lines.
When the device is very much in a board, if distribute it as the differential lines: one problem is PCB area is too large, the second problem is should be distribute into 2N lines heavy workload, It is very difficult, so the actual needs of the people for the proposed multi-layer PCB the concept, The typical is the double-sided PCB board. The bottom layer as a common reference circuit wiring ,so only distribute N + 1 lines, PCB layout is also greatly reduced
Common reference circuit, we often say that the reference ground, for most embedded industry, because the signal is digitized ,signal quality requirements is not very high. Using whole Layer of reference ground not only reduce the board size, but also improve efficiency , it saves time. In fact, the board is reduced to shorten the length of the signal line, and some may be offset because the reference to the signal quality degradation caused problems, so in practice, such incorporation by reference to the effect of PCB layout, the difference was similar to the ideal model line
In the dual-panel design, usually there are often cross-line, you need to do cross-line jumper to ground switching, noted that this jumper can not too long, if too long, easy to split reference ground, especially for some signal line high quality requirements, refer to the bottom it can not be split. Otherwise the signal circuit was completely destroyed, reference ground line will be useless. generally speaking, reference ground line only suitable for short jumper with signal lines, signal cables distribute on top layer, or use more layers of PCB board
PCB layout carrier is a PCB board, general reference ground to the PCB edge 1mm from nearby, the signal from the reference line to the near edge of 1mm, so the signals are confined within the PCB board, this way can be reduced EMC radiation
Wonderful PCB Limited is a manufacturer specialized in producing various circuit boards of high technology content and high quality requirements, as a well-known supplier of single and double side, multilayer, blind buried hole aluminum board and flexible circuit board in the world, Wonderful also provide one-stop service of PCB manufacturing, PCB assembly, PCB components purchasing, and PCB function test for both domestic and foreign customers.
Since its launch in 1996 , by all the staffs’ years of effort, and full support from different sectors of the society, with the high quality products, Wonderful PCB Limited obtain support and trust from all kinds of electronics manufacturers around the world, with continuous stable increasing output, the company scale get rapid development.
Wonderful PCB (HK) Limited registered in HongKong in 2002. By the end of 2007, total assets is nearly one hundred million CNY, factory building area of 20000 square meters, 700 staffs in workshop area. After expansion again in 2010, the monthly output over 40,000㎡, output of single, double side and multilayer FPC over 5000㎡, after many years of struggle and enterprising of all colleagues, We Wonderful has abundant technical force, rich management experience, advanced production equipment, perfect detection means, as well as the comprehensive management and after-sales service. Our products are widely used in communications, medical, industrial control, home appliances and other fields, in addition to occupy the domestic part of the market at the same time, exported to southeast Asia countries and regions in Europe and America.
Nowadays, under situation of increasingly competition in technology, Wonderful PCB Limited increasing invest in technology research and development on and on, to cooperate with clients for all kinds of printed circuit board of high, refined, sharp demand, our company introduces Germany, France and other advanced production equipment, relying on scientific management, has trained a number of highly qualified professional talent team, at the same time with high quality products, reasonable price, fast lead time, good after-sales service to serve all customers.
Wonderful PCB Limited adhere to the “customers first Integrity-based “spirit of enterprise, using advanced management ideas and methods, adhere to considering the customer as the focus, with excellent after-sales service to serve masses of customers, product quality with reference to the IPC standards and the United States military standard MIL, and through ISO9001 quality assurance system, UL safety certification and the ISO14001 environmental certification system, such as quality guarantee, provide safe and reliable high quality products to you.
In the process of construction of diversified development of enterprise, Wonderful PCB limited adhere to “to the ongoing training to improve staff quality” of the enterprise culture idea, pay attention to talent cultivation, building learning organization, through effective training, improve personal comprehensive quality, cultivation and improve the corporate culture, creating a modern service team, for Wonderful PCB, ensures Wonderful PCB can continuously to provide customers high quality products and quality and efficient service.
Company take the high technology as a starting point, using world first-class level of equipment and raw material for production and consider high-precision sales, high-density multilayer circuit board as the development direction of our products and technologies, to be built into “First-class PCB enterprise” as our vision, “provide high quality PCB products and sincere complete PCB products one-stop service to electronic information industry” as our mission.
The reason PND (Pits and Dents) pits and depressions occur: fish any fines particles adsorbed by the edges due to static electricity, the upper plate residual water Material of the active air drop of dust and debris attached to the copper plate. Solution: identify the problem immediately to re-grind plate and, after washing on the line of the most fundamental solution to reduce staff contact and exposure to air time, to complete the clean room stacked combination of cutting and automatic installation of devices to eliminate static electricity.
SLP (Slippage) slip occurs: piece of content R / C high and flow R / F is greater than the pressure is too easy to produce timely, and every pot temperature is too large and cause uneven flow substrate per pot Chan will lead to poor positioning piece slip responses: Chan piece R / C, R / F high vertical machine (or water Liquidation machine) can also alter the conditions on Chan laminated CYCLE such as reduced heating rate as amended, postponed the pressure, reduce stress, if a larger temperature difference between each pot can reduce tension lowering capacity to overcome the poor pay more attention to improving the positioning operation.
Dry (Dried Laminate) board dry Analysis: Poor glass cloth coupling agent compatibility with resin resulting in poor wetting. Or piece over so that timely pressure hardening resin flow is bad if found to have low flow pcb board that will produce dry, this condition at the time of solder measured prone stratification. Solution: glass cloth surface finish problems, please materials manufacturers improved low traffic reduces varnish water of time or improve piece flow of time and, if not serious Dry Lamination may amend conditions such as increased temperature rate, the pressure on early, increasing pressure.