[time-nuts] Slightly OT: inexpensive USB analog-digital converter?
phk at phk.freebsd.dk
Fri Jan 18 04:59:21 EST 2008
In message <20080118095515.8B26BBE34 at ip-64-139-1-69.sjc.megapath.net>, Hal Murr
>> (My goal is to add digital voltage and current monitoring to some
>> older bench power supplies.)
>Measuring voltage is simple. If the input range is too big, you need a few
>resistors. If it's small, you lose a few bits from the top of the A/D. Add
>an op-amp if you need them.
>Measuring current gets tricky.
Actually not, there are several good chips like the INA197.
Or the very simple way, buy a suitable hall-effect current monitor
like LTSR from Lem.com.
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