Hi,
I had similar problem, but I solved another way (maybe also of interest):
I used a PIC having a PWM module built-in (eg. g. 16C74 in my case). The
PWM output drove a 741 and I put it on the 4-20mA input of the VFD with
such a resistor, that the highest current (including the built-in resistor
of the VFD) reaches 20mA. Of course, I applied some filter to make DC from
the PWM signal. It is cheap, reliable and it works fine.

I hope this helps.

Imre


On Sun, 25 Jul 1999, alpha1 wrote:

> Hi,
>
> Need example circuits for PIC to control a DAC(like DAC0800/0807/0802 or
> others suggestions).
>
> The output shall be  0-10VDC to control a VFD(Variable Freq Drive like DANFOSS
 inverter).
>
> A short code example also fine.
>
> rgds
> -pklee
>
>