3 PCB Design Experience

1. if the PCB design of the circuit system contains the FPGA device, it is necessary to use the II quartus software to verify the distribution of the pin before drawing schematic diagram.

2. 4 layer PCB board from top to bottom is as follows: the signal level, power supply and a signal plane layer; 6 layers from top to bottom in turn: signal level, signal in electric layer, signal electric layer, power supply, signal plane layer 6 layer above the plate (advantage is: anti radiation interference), priority in their choice of electric layer wiring, walk not to open plane layer prohibited line away from the ground or power supply.

3. Multiple power system wiring, such as FPGA DSP systems do six plates, at least in general will 3.3V 1.2V at 1.8V 5v.3.3v is generally the main power supply, direct shop power supply layer, through holes easily buton global power supply network.

5V generally may is the power input, need only in a small area of the copper paving. And as far as possible (you ask me the more thick, crude more rough, the thick, the better) 1.2V and 1.8V is separated from the kernel power (if the line is connected with the way will encounter great difficulties in the face of BGA devices), layout as 1.2V and 1.8V, and let 1.2V and 1.8V connected component placement in a compact area, the use of copper skin connection.

In short, because the power network throughout the entire PCB, if the use of the way the line will be very complex and will be around a long way, the use of copper clad method is a good choice!