🚀 go-pugleaf

In article <1992Apr5.215721.11408@willamette.edu> agulhati@willamette.edu (Ashish Gulhati) writes:
>Relays switch the interface from one power suppply to the other as needed.
>Tri-state drivers from each power supply drive the interface...
>... going to either damage the tri-state devices or make them introduce
>noise into the system? Or is the connection to them literally an open circuit
>that I can forget about once I've disabled them? 

The connection is an open circuit with one exception:  you still have to
observe the limits on voltages that can appear on those pins.  If the two
power supplies are far enough apart that signals from one side go outside
the voltage limits on the other side's (disabled) tri-state devices, those
devices can be damaged.  Perhaps enough to ruin them, perhaps just enough
to make the system unreliable.  Those limits are not very wide; tri-state
devices aren't meant for this kind of thing.
-- 
GCC 2.0 is to C as SVR4 is to Unix.     | Henry Spencer @ U of Toronto Zoology
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