Any good Vrms to Vdc converter

[Angelo]

For a project where I need to measure an inductor (detection loop) at 60kHz, I plan to use RMS to DC converters: one to measure voltage across de inductor, and one to measure current across a sense resistor.
Then measure phase between voltage and current with two zero crossing detectors to generate digital pulses.
L is the easy to calculate and display.

Is there any good device for RMS to DC conversion ? Idealy a model with evaluation board, to be used for the prototyping phase.

Thanks for any tips

Angelo

 

[PaulS]

I tend to use Google Gemini (the one that shows as the "AI Mode" button in the Google Chrome browser) as a starting point for this kind of research.
Gave it your complete question, and this is what it came back with: https://share.google/aimode/BTSTkZvatyzXHLvOZ . Perhaps helpful?

Paul

 

[MarkT]

Vrms is the same as Vdc for power dissipation in a resistor - you are effectively wanting to synthesize a single-ended low-bandwidth signal with same power level. To convert an AC signal to a DC signal with the same Vrms as Vdc involves using an analog multiplier, low-pass-filtering and then analog square-root conversion!
These days it would be done in software using an ADC and a DAC. You also need to worry about whether to count DC offsets on the AC signal or not.

This seems like xy-problem territory - simply send both AC signals to ADCs and do the analysis in the digital domain directly.

If you know you have sinusoidal waveforms only you can simply use a peak-measuring circuit or a precision rectifier to get a DC voltage in the analog domain. This is much simpler than true-rms.