Clear PCB Design Goals
Before designing a printed circuit board, you should clear your design goals. As a saying goes, well begun, half done. Enough time paid to clarify your PCB design goal is really deserved. For example, you should make sure it is a common PCB board, high-frequency PCB board, small signal processing PCB board, or any other type.
If your board has more than 40MHz signal line, you should consider more for these signal lines. If the frequency is higher, the wiring length will require more strict restrictions, and more attention must be paid to the interaction between the high-speed circuit and its connection which are really important in a printed circuit board design.
If your printed circuit board only owns millivolt or microvolt weak signals, you really need to pay special attention, because weak signal is easily influenced by strong one. To protect your weak signal, often shielding measures are useful.
Board adjustment measure, physical location of the test points, and isolation test points in the design phase all cannot be ignored, that’ because some small-signal and high-frequency signals cannot be directly added to the probe to take the tests.
Moreover, we should consider some other relevant factors, such as the board layers, board mechanical strength, etc.