[sdiy] OT: High voltage diff amp

[Grant Richter]

If you can AC couple then, simplest would be a signal transformer.

This provides differential to single ended conversion, and dielectric  
isolation is usually a 1000 volts or better.

If you have to have DC coupling then an isolation amp is the only  
option I know of.

This can be a voltage to frequency converter through an optocoupler  
to frequency to voltage converter.

They might still make "chopper amps" that turn the DC into AC by  
chopping, run it through a signal transformer, the rectify it to get  
the DC back.


On May 25, 2006, at 7:05 AM, Antti Huovilainen wrote:

> Hi
>
> I have a signal (few volts) riding on top of high common mode  
> voltage (few hundreds of volts). I need to isolate only the  
> differential signal. Any advice on how I should approach this?
>
> It's relatively low frequency (basically pulsed DC). Super-low cost  
> is not a requirement but I'd prefer to keep the unit affordable.
>
> Antti
>
> "No boom today. Boom tomorrow. There's always a boom tomorrow"
>   -- Lt. Cmdr. Ivanova