Charles Craft wrote:
> I'm guessing SH* is a shunt?
>
> What are SH1, SH2 and SH3 for?

I call them "shorts".  They are ways to break up nets in Eagle even though
both sides are connected to each other.  Sometimes this is done to have a
differnet net class on each side, sometimes its to guarantee all the current
between the two subnets flow thru a single point that I can manually place.
This is the case for SH1 on page 1 for example.  It connects the power
section GND-PWR to the main ground for the rest of the board.  The switching
power supply can have large current spikes flowing accross its ground, which
I want to keep off the main ground.  The switcher will connect to the rest
of the circuit only at its ground and output points so all the large
internal currents don't cause ground offsets all over the board.  I may need
another short at its 5.5V output, or just make sure that the output funnels
thru one connection during layout.  I often add shorts once I start working
on routing, especially when using the auto router.


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