Leslie Newell wrote: > Hi Jon, > > It would probably be easier to do it digitally. Tachos make the most > difference at low speed and you could get a much smoother and more > accurate low speed signal by doing it digitally. > > Two charge pumps wouldn't work because the quadrature signal is > symmetrical at all times. You would need to decode the quadrature signal > into step/direction then feed the step signal into a charge pump and use > the direction signal to invert the voltage. This doesn't work, as it will show a non-negligible magnitude output rapidly switching polarity due to encoder dither. It needs two matching, opposing current pulses that will cancel out when the encoder is dithering, giving a very low magnitude output. Yes, I need to decode into step/dir, or better, into a step - and a step + signal, each feeding one of the opposing integration inputs.
Jon ------------------------------------------------------------------------- Sponsored by: SourceForge.net Community Choice Awards: VOTE NOW! Studies have shown that voting for your favorite open source project, along with a healthy diet, reduces your potential for chronic lameness and boredom. Vote Now at http://www.sourceforge.net/community/cca08 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
