Poul-Henning Kamp wrote: > In message <[EMAIL PROTECTED]>, Richard Moore wri > tes: > > >>> If you are controlling this with a microcontroller, there is an >>> alternative >>> you should consider: >>> >>> Use only a single DAC and then PWM modulate its output, followed >>> by a low-pass filter. >>> >> Poul, how do I PWM a DAC that is itself a PWM device? This question >> is prompted by the DAC I'm using in Bert Zauhar's FLL GPSDO, which is >> a dithered 10-bit DAC in a PIC chip that results in 14-bit >> resolution. I'd like to have a simple way to get 2 to 4 extra bits of >> resolution out of this. Can you recommend some design resources to do >> this? >> > > I would simply cummutate the DAC output with a PWM controlled fet or > CMOS switch. > > You can either do this with the filtered DAC output and filter the result, or with some ingenuity just combine the unfiltered PWM outputs and then filter the result with a single low pass filter.
Bruce _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
