Re: [CAD_CAM_EDM_DRO] Sinosidal Encoder signals to TTL signals converter

juan gelt wrote:

>no. it doesn't help a bit.
>google helps. babelfish helps. as a last resort, why
>not call up heidenhahn? they might know something
>helpful since they make these things all day long...
>why me, lord?
>when you've done your homework, go to #electronics on
>efnet and get answers in a minute.
>
>

Actually, it helps quite a lot. 11 uA is the standard signal on
Heidenhain analog scales. If you put a 1 K Ohm resistor
between the encoder signal and ground, you will get a voltage
of 11 mV. You can set up a comparator chip, like the LM193,
to compare that voltage to a threshold that you set to be
in the middle of that voltage swing. So, if the 11 uA is set
up with one peak at zero and the other peak at 11 uA, you'd
get a voltage swing from zero to 11 uA. In that case, you'd
want to set the threshold at 5.5 mV. If the current swing has
some offset, you'd need to set the threshold higher (or lower)
to get approximately equal times where the signal is above
and below the threshold.

Jon