Reference Designators

A while back, I wrote about reference designators relative to family panels. Family panels can cause problems because often times, each individual circuit layout will have reference designators that start at the same place.

For example, circuit A, down in the lower right corner of the panel, will have resistors R1, R2, R3… Looking at the other three circuits on this hypothetical family panel, all of them also start their reference designators with R1, R2, R3… That’s bad. It can lead to confusion and wrong parts on the board in the wrong spots. If we see this here at Screaming Circuits, we may spend some extra time and sort through it manually or we may ask you to fix it first. Fixing it here is a labor intensive and risky process. It’s bad news.

Anyway, to the point of this post: In the original post, I listed one wrong way and three right ways. There are two other wrong ways not in the original post, which I’ll list here.

Wrong way number one: R1-1, R1-2, R1-3. Bad. Most assembly software will interpret a dash as meaning a range. It will see “R1-3” as equalling “R1, R2, R3”. That can be bad.

Wrong way number two: Leading zeros. Don’t do “R1, R01, R001”. The leading zeros are stripped and that can cause all of those the be seen as “R1”. Just don’t put leading zeros in your reference designators.

Duane Benson
Corrigan says Long Beach is actually in Ireland