Re: Chopper Transient Suppression

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mariss Freimanis"
<mariss92705@y...> wrote:

>
> .2uS is way to short. The motor winding capacitance results in
> ringing (multiple cycles, underdamped envelope) for several
> microseconds. We use a 5uS blanking period (comparator ignore time)
> at the start of each switching cycle.
>
> Don't depend on the I-sense RC low-pass filter; blank it digitally.

Mariss:

Thanks. I cranked the blanking up to 4uS and the stepper motor
vibration is now gone. The stepper motors still produce
a high pitch screeching noise. Since I've never actually
seen or heard anybody else's CNC machine to compare against,
I have no idea whether my stepper noise is typical or excessive.

Thanks for the prompt feedback.

-Wayne

[snip]