Electronic products in the CE certification, often need over-radiation interference (<1GHZ) testing, often encountered a frequency point on the radiation (dbuv/m) exceeded, or the situation of insufficient allowances:
1. If the low-frequency exceeded, the general is the input power radiation out, to ensure that the use of DC adapter qualified, and then the PCBA board power input processing, usually wire string beads, capacitance to ground and other processing.
2. If it is high-frequency exceeded, the general is a clock (system clock, crystal clock, peripheral chip clock foot) of the multiplier radiation, first determine which chip leakage, and then see if there is a pin direct lead line out of the chip (sweep the lamp pin, adkey pin, etc.), if there is, to reserve the bead, capacitance. It is also possible that the power supply line radiation out, but also to do the corresponding treatment.
3. If there is a high peak, which may be some of the clock variable chip radiation (SD card clock foot), first confirm that the SD card shell is properly grounded, power processing, and then the clock foot and the data foot processing (generally not recommended strong push operation).
For electrostatic testing, first confirm the need to touch the number of V (General 4kV, Brazil 6kV), air hit how many V (General 8kV).
1.PCB to reserve an ESD component pad, all the holes, and the outside communication ports are to be processed accordingly.
2.PCB layout and wiring, to lay copper treatment, so that static safety and smooth back to the ground.