AC+DC voltmeter analogue front end.
I have the digital circuit complete but am in need of help for the front end from input to ADC.
The input is two terminals from which I need to create two channels for differential measurement. One ch is AC the other for DC
Circuit inputs two terminal
DC +/- 5VDC (typical, though must be tolerant of voltages up to 60VDC
AC 30Vrms(typical though must be tolerant of voltages up to 12V p-p
Power supply = single supply at [url removed, login to view]
2x channels ready for ADC (my ADC is 16bit with a PGA on the front.)
The ADC is two x differential channels +/-6vdc each.
Split the input into two differential channels.
Ch1 ranged +/-6VDC but tolerant of higher voltages which could be shunted or blocked. To allow for this the input my need to be attenuated then amplified
Ch2 ranged +/- 6VDC (or =-6VDC you choose) where rms on the input site ~= VDC on the output side. 0 volts RMS could equate to 0VDC or -6VDC. The latter is preferable.
I would like accuracy better than [url removed, login to view] for the DC channel and better than [url removed, login to view] for the AC channel.
The high input impedance is critical I would like to avoid resistive dividers on the front end.
One idea that I have had is:
For the DC channel:
Attenuate and clamp Instrument amp
For the AC channel:
Attenuate and clamp Instrument amp True RMS Converter
The outputs need to be linear with respect to input, though I can calculate scalar constants after creating the circuit.
You must provide part numbers for all IC’s and values for all passive components as well as a circuit diagram.
15 freelance ont fait une offre moyenne de 263 $ pour ce travail
Hello, good morning. I am heading a startup, we will deliver you complete schematics, BOM and pcb layout (if required). Please feel free to contact us. Best Regards, Shahbaz.
Hi, I can certainly do your work, i have more than 8 years of experience in this, kindly do reply me to discuss the project details with me. Will wait for your reply! Thanks