Gecko Pulse Multiplier

Ernst,

I am not using pulse doubling. The way the pulse multiplier works is
as follows:

1) The STEP pulses you send clock a 4-bit DOWN counter.

2) A wide dynamic range (20Hz to 200kHz), non-linear (logrithmic V in
vs. F out) VCO sends its pulses to variable modulus counter (divide
by 1, 2, 4, 5, and 10).

3) The output of the modulus counter clocks a 4-bit UP counter.

4) The outputs of the UP and DOWN counters go to the inputs of a 4-
bit ADDER.

5) The 4-bit output from the ADDER (SUM) goes to a non-linear D to A
converter.

6) The output of the D to A goes to a PID compensated ERROR
amplifier, whose output then goes to the VCO, closing the loop.

7) The SUM is also compared against a reference value. If it equals
or exceeds this value, the VCO is synchronously shut-off until the
next STEP input. This prevents the VCO from ever generating more
pulses than the called-for multiple of the STEP input.

8) The VCO output is buffered and sent on to the motor drive.

Unlike a one-shot, the resultant VCO pulses are evenly distributed
with time. That is to say, if the modulus is 10, there are 10 evenly
spaced VCO pulses over the STEP pulse period. They maintain this
distribution regardless of the STEP pulse frequency. Below a STEP
frequency of 2Hz the VCO pulses come in bursts of 10, .5 sec per
burst.

All this requires 8 ICs, 24 resistors, 9 capacitors, 3 transistors, 2
diodes, a dual opto-isolator and 9 dual header pins for option
jumpers. It all fits on a 1.25" by 1.375" by .125" (32mm by 35mm by
3mm) module that fits snugly inside either the G201 or G320 drive.
All surface mount components of course.

Mariss

--- In CAD_CAM_EDM_DRO@egroups.com, Ernst Aardal <eaardal@o...> wrote:
> I just wonder, when you use frequency (pulse) doubling you must use
a one shot monostable.
> How long is each puls in the 1x and 10x mode.
> Is this a box that you can supply for other stepper-amplifiers?
> Ernst