In the PCB board layout , the power and ground handling is very important to make noise generated by power lines and ground down to a minimum to ensure the quality of the product.
Power and ground wiring rules are as follows .
· Between the power supply and ground plus decoupling capacitors .
· Try widening power lines, ground width , it is better than the power ground wire width .
· Digital circuits available PCB ground wire to form a wide loop , constitutes a ground network to use, not so analog circuits to be used.
· Copper layer with a large area for the ground on the PCB is not a place to spend connected with the ground as the ground with , or made of plywood, each occupying power and ground floor .
. Check the rules
After completion of wiring design , layout design needs to be carefully checked whether the rules established by the designer , but also need to confirm whether the rule meets the requirements established by the PCB production process , general inspection following aspects .
· Lines and lines from the line and component pads , line and through holes , pads and through-hole components , through-hole and through hole between reasonable, whether to meet production requirements.
· Power line and ground width is appropriate, whether the tight coupling ( low impedance ) between the power supply and ground , whether there can make the PCB ground widened place.
• For Key 's signal cable is best to take measures, such as the length of the shortest line added protection , input lines and output lines are clearly separated.
· Analog circuits and digital circuits if there are separate ground wire.
· Is the added PCB graphics ( such as icons, subscript ) will cause the signal shorted.
· For some ideal linear modification.
· Whether the PCB plus a processing line , solder meets the requirements of the production process , solder size is appropriate, whether the pressure in the device character logo pads fine .
· Multilayer formation in the frame power supply is reduced, such as power -board strata exposed copper is likely to cause a short circuit.
