Calculating the correct Voltage Output CT

[phoenix (Jeff)]

Thanks for the reply.

@Robert.Wall

I’m guessing that the ADC’s Vref also represents the maximum input voltage that can be converted accurately. The data sheet should make it clear what the input voltage range is.

Yes, sorry, it’s range is 0V to Vref.

@Robert.Wall

If your input is a nice clean textbook sine wave, 1100 mV peak-peak is 389 mV rms

I can’t quite get my head around this.

@Robert.Wall

I think a standard 0.333 V rms voltage output c.t. will be suitable

OK, that I can follow - thanks

@Robert.Wall

@phoenix

The vin voltage I’m working with is 3.3v,

I’m not sure what you mean by this - please explain.

The input voltage (5v on this diagram, that I’m using for reference) will be 3.3v. I mentioned it for completeness, I don’t believe it has any impact on the calculation that lead you to 389mV rms.