On Tue, 27 May 1997, Pioneer Microsystems wrote:
>
> To achieve your goal of bipolar, I have a dirty trick you can try to get
> around a 'special' DAC.  Use a unipolar device, and then add a sign amp on
> the other end.  Take a 'good' IE. OP07 amp, set it up like a classic diff
> amp with four resistors, tie the two incoming resistors together to the
> signal, and replace the resistor that goes from the + pin to ground with an
> open collector to ground instead.

I don't understand the last step, what to you mean ?

Bye,
Antonio Almeida