일반 PCB ROUTING 방법

 PCB라우팅 방법에 대한 일반적인 공부

 

Place decoupling capacitors as close to the target device as possible.

 

-> 디커플링 커패시터는 타겟 디바이스에 가능한 가까이 배치해주세요.

 

Place bulk capacitors in close proximity to their respective power supply

 

-> Bulk cap은 power supply에 가능한 가까이 배치해주세요.

 

All transmission line conductors should be adjacent to its reference plane.

 

-> 모든 Net는 기준 GND에 인접해야 함

 

All microstrip nets should have a ground plane directly adjacent to the respective trace

 

-> Top, bottom에 위치한 net는 기준 gnd plane에 인접해야함

 

 

All stripline nets should have a ground or power plane directly adjacent (top and bottom) to the

respective net where possible. If it is not possible to enclose the respective net within a ground/ground

or ground/power stack-up, then at least one return path must be provided for proper operation.

 

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Vias and escape vias to and from the device shall be taken into account with regards to timing,

reflections, loading, and so forth.

 

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6.2 Application Board (PCB) Layers Different applications dictate different layer design (stack up). Most HPMP application boards range between 10 and 18 layers. Choice of signal routing layers can impact single quality, skew, and propagation delays. Differential signals must always be routed on the same layer. Criteria for determining whether the clock signals are routed on an internal layer (strip line) or external layer (micro strip) depend on the application and requirements. If propagation, visibility, accessibility, or timing is a major concern, then remember that signals routed on an outer layer (micro strip) travel a bit faster than signals routed on an inner layer (strip line). If noise immunity or noise susceptibility is a concern, then a strip line (internal trace) buried between parallel power and ground planes would be the proper choice. If signal integrity or performance is the criteria, then either is acceptable provided proper spacing is maintained, and the impact of parasitics minimized (vias, stubs, coupled components).

 

한마디로 속도가 중요하면 외층, emi, 커플링이 걱정되면 내층을 써라