"Ulrich Bangert" <[email protected]> writes: >> -----Ursprungliche Nachricht----- >> Von: [email protected] >> [mailto:[email protected]] Im Auftrag von Jan Fredriksson >> Gesendet: Mittwoch, 8. Januar 2014 09:25 >> An: [email protected] >> Betreff: [volt-nuts] PWM voltage divider >> >> >> I'm thinking of using a PWM divider for voltage generation of >> adjustable DC voltages from a voltage reference. >> >> Does anyone have any pointers to circuits, solutions, >> topologies, error analysis etc. for such solutions? >> >> Jan > Jan, > > with standard PWM generated from a microcontroller the repetition rates of > the signal may get VERY slow with higher resolutions, making it difficult to > make a pure DC signal from. You should consider to use a Sigma-Delta DAC > which is very easy to program in a microcontroller. I have used AVR Megas > with software Sigma Delta DACs and precision analogue multiplexers to switch > between the reference and GND up to 20 bits of resolution. Worked fine! > > Best regards > Ulrich
Another approach is to combine a "coarse" and "fine" PWM (as Fluke do in their calibrators I think). -- John Devereux _______________________________________________ volt-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
