At what point do you stop optimizing routing and accept a "good enough" PCB layout?

beginners
1

Hi all,

I’m working on a relatively simple mixed-signal board (microcontroller + sensors + switching regulator), and I keep finding myself making small routing improvements that then force changes elsewhere.

The board is already electrically correct, passes DRC, and the manufacturer has no issues with the Gerbers.

However, every time I review the layout, I see another opportunity to:

shorten a trace
improve component placement
reduce via count
improve ground return paths

At some point the improvements become marginal, but it’s surprisingly hard to decide where to stop.

I’m curious how experienced Fritzing users decide when a layout is finished enough to send out for fabrication.

Do you have any practical rules of thumb?

2

It is likely that your microcontroller is not getting much of critical signals, unless you are running a bus at high speed. So I would leave the microcontroller in a functional state.

Your sensors likely have a low read speed too, functionality is key.

Your switching regulator (I assume external inductor) on the other hand benefits from optimised routing, ideally away from signal lines (edge of board?) to not become an angry inefficient screamer. This is where I would put the focus on.