circuit board,pcb prototype,pcb assembly,pcba manufacturer

What should be considered in PCB design

1, PCB manufacturing requirements

Clear requirements for plate, plate thickness, copper thickness, process, resistance welding/character color, etc.The basis of the above requirement is to produce a board, so R&D engineers must write clear, I have contact with the client, gree is doing relatively well, the technical requirements for each file all write very clear, even if is at ordinary times we think that the normal white with green solder resist ink characters are written in the technical requirements, and some customers is to forgive, forgive, what all don’t write, as issued to the factory proofing production, especially some manufacturers don’t write some special requirements, result in factory after receive the email, first thing is to consult this requirement, or make some manufacturers finally does not conform to requirements.(PCB design)

PCB design

2, Design of PCB drill hole

The most direct and biggest problem is the design of the minimum aperture. Generally, the minimum aperture in the plate is the aperture of the overhole, which is directly reflected in the cost. Some of the overhole of the plate can be clearly designed as 0.50mm hole, i.e.Another is via too much, some DVD and digital photo frame of the above via really is filled with the whole plate, easily 1000 porous, has done too much on this board, should think normal in 500-600 – well, of course, some people would say via signal conduction of the board, and heat dissipation is good, I think it will take a balance, in the control of these aspects at the same time also will not lead to rising costs, I can say, for example here:Do we have a company the customer is shenzhen DVD, the amount is large, more than at the time of the first cooperation is also this kind of situation, then the cost for both sides, it’s a big problem, after communication with R&D, will be a hole aperture to increase, delete large copper sheet on the part of the hole, like the middle of the main IC ventilation replace with 4 3.00 MM hole, so that the drilling cost was reduced, the square can drop a few dollars of drilling cost, for the two sides reached a win-win situation;Another is some slots, such as 1.00 MM X 1.20 MM of ultrashort slots, for manufacturers, is really very hard to do, first it is difficult to control the tolerance, the second drill to slot is not straight, some bent, we also do some of this before the board, a few yuan RMB plate as a result, because of the slots is unqualified, deduct $1 / piece, we also communicated with customers this aspect of the problem, then directly convert the 1.20 MM hole.(PCB design)

PCB

3, PCB circuit design

For line width line spacing, as well as open circuit short circuit, etc., is the most common manufacturers, set aside special, some conventional board, I think the line width line spacing is bigger, the better, of course, I have seen some files, one could go straight line, must have to appear a few curved, with several big small go same thread, different spacing, distance is only 0.10 MM in some places, for example, in some places there were 0.20 MM, I think R&D in wiring, must pay attention to these details;In addition, the distance between the line solder pan and the large copper sheet is only 0.127mm, which makes it more difficult for the manufacturer to deal with film. It is better that the distance between the line and the large copper sheet is more than 0.25mm.Some go line away from the safe distance of peripheral or V – CUT is small, factory can move well, some must be good to do, be sure to R&D design even have not the same network line together, and some of the same network, i.e., why didn’t even, at the end of the manufacturers to communicate with R&D, is found to be short circuit open circuit, and then to modify the data again, this is also not a few, experienced engineers might be able to see, inexperienced only follow design file, the result is either modify the file to proofing or use the blade scraping or fly line, for plate line impedance requirement,Some R&D also do not write, also do not accord with a requirement finally.Other boards have holes in the SMD PAD that leak when soldered.(PCB design)