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Joel Koltner[_2_] Joel Koltner[_2_] is offline
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Default critique SMT pcb ?

"John Larkin" wrote in message
...
The board looks fine. A couple things are a little unusual, like the
angled connection into R11-R12 and into R4-R5 and R13, but that's just
a matter of style.


The R11-R12 connection has an angle less than 90 degrees on it, which
historically people would tell you not to do due to it being an etchant trap
and not etching very well. I haven't heard an actual PCB shop say that's a
problem for ages, although they're still handing out that "advice" at
seminars... at least the ones we had some techs go to last year. (They also
came back with the idea that, for about 20 signal lines that never move at
more than a MHz -- and only a few move at more than kHz -- they needed a 50
pin connector with a power or ground connection on EVERY other pin for the
sake of signal integrity/current return path loop minimization/etc. as well as
a 100nF cap from EACH ONE of those power pins to the respective ground pins.
:-( I made them get rid of the excess caps but let them keep their 50 pin
connector since we had the real estate and one battle was enough for one
day...)