Hello Every one
I am a freelance PCB designer for micro and small companies for the past 15 year. After struggling for 12 years I can tell with some confidence I have a hold on designing.
My fight for the following continues
1. How can I know where to keep which component to where so that routing becomes easy
use schematic driven placement.
2. How can I reduce the mistakes
use cad software with realtime DRC and plug design rules from schematic. ( trace width and spacing )
3. How can I anticipate the completion time
experienc.e can't help you there. this depends on person to person ...
4. Which strategy to follow "place and route" is best or" place route place "strategy
it depends. i work in 'blocks'. place circuitry around a chip ( decoupling caps for digital stuff for example and the associate power ground spiderweb ) , or a quad opamp chip with all the passives around it. then place this block close to the other blocks or connectors it mates with. this is all very trivial if you use schematic driven placement.
5. How can I preserve the mental strength till the end of the design phase
here's what work for me :
pepsi ( with real sugar as opposed ot corn syrup )
youtube playlist with some thumping music... zztop's sharp dressed man ,legs , perfect for routing high density boards ....
6. How can I upgrade the knowledge and tech advancements.
read blogs , IPc documents, there's free magazines you can subscribe to that help you stay sharp.
here is my layout strategy.
define board contour, mouting holes , no-go-area's. this is often dictated by the housing.
place 'unmovable parts' : connectors , switches, displays.. anything that sticks its head out of the box , or needs to mate with another assembly.
place 'bulky' stuff like large heatsinks , fat capacitors depending on headroom.
freeze at this point.
take a look at the power supply section first. stick that in its corner of the board, close to the power input and do the layout so you can break out easily on different layers / split planes.
place the 'critical stuff now ( noise sensitive things etc ) . use schematic driven layout. ( select the parts that belong together in the schematic , switch to pcb and place one by one from this selection. use the ratsnest to rotate and get the parts in a setting. rotate and replace parts to get a clean ratsnest. plunk down tracks and freeze this block.
repeat for other blocks.
move blocks into their location on the pcb ( close to their input/output pathways such as connectors etc. )
and so on...