Re: Servo/Spindle motor ammeters?

It depends on how much work you want to do. You could build it with
that chip, but I have doubts that you could drive the reference input
with the internal voltage reference. To get the voltage reference down
to where the full-scale voltage at the current sense resistor is,
you'd need to connect a resistor somewhere in the range of 100k to 1M
between the ref out pin7 to the ref in, pin6. It wouldn't be very
linear, but it should work.

A better solution would be to drive the ref in (pin 6) with a buffered
reference voltage.

It depends on your purpose -- if it's a quick glance indicator of when
you're in trouble, the resistor between pin 7 and pin 6 should work
fine.

If you tell me the full-scale current and the value of the current
sense resistor, I'll tell you what value to use and how to hook it up.

On 7/13/06, afogassa <afogassa@...> wrote:
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Dennis Schmitz" <denschmitz@...> wrote:
> >
> > Don't do that, open up the drive and find the current sense resistor
> > and hook one of these across it:
> >
> > http://newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=01K5532
> >
> I want that too..., but I was thinking about a bargraph indicator,
> could that be made with a lm3914 it's a bargraph driver ?
>
> Fogassa