hi
my question is general but suppose you want to start designing a PCB including a regulator(LDO and Switching) a microcontroller , a GSM Module , some I/O like RS485 , LCD , EEPROM , ....
we assume that schematic is ready and we want to design PCB.
as for me i follow this strategy:
1.define rules.
2. component placement :
i do this base on signal flow in schematic to get best and shortest connections , at this step i do not consider power connections i jest pay attention to the signal connections.
3.route power traces:
at this step i route power signals with star topology and distribute it among my pcb modules and components.
3.route signal traces:
i first route high speed and important signal traces like USB Diffpaires , RF traces , ... and do impedance matching and length matching
then i route other signals like uart , led , gpio , .... . also i assign or update io's of my micro controller in my schematic in this step in order to get better arrangement
what is your strategy ?do you see any problem in my strategy?
please consider that the pcb should pass EMI and EMC and other environmental tests
any thing that improve PCB Design skill will be appreciated.