Hi Brusque,

not too sure what you mean by 'safer' here, personal injury or bits of the circuit frying ?
anyway...


Assuming here that you are suggesting that the '0v' reference is one of these two output pins, you
now have a situation where that reference swings from +vmax/2 to -vmax/2. i.e. the measurement is
now 'floating'

I am sure there are occasions where this might be useful (possibly even in this situation, but I
don't know anything about the rest of the circuit), but on the whole I think I would prefer to use a
fixed reference point, especially as you would need an isolated supply as you suggest - or at least
one that tracks the reference.


the circuit I was suggesting was:

          v+
          _|_
          /|\    < diode!
           |
--R1--+----+------- output
      |   _|_
      R2  /|\
      |    |
------+   v-
      |
    0vref



This should work fine. I have done something similar to this before, although I vaguely remember not
needing a -ve rail somehow... not too sure though. Will check at home tonight if I can find the
circuit.

Regards,
Simon

p.s. any of you know if there are any ascii schematic capture programs out there? my diodes look
pretty poor ;)




>    ---R1----+-----
>             |
>input       R3    output
>             |
>    ---R2----+-----

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