Hi all!

I am trying to implement control loops with the pwm output of an
16C73. As I am not an engineer, I don't have the theoretical
background to do it properly myself. The following two projects are on
my mind:

1. A more or less stabile adjustable output voltage 0..4V that can
source a current of 0..1A. I thought of the following schematic:

---------------+
               |    feedback
     A/D input +------------------------------------+
               |                                    |
               |                   +5V              |
16C73          |                    /               |
               |      +-----+     |<                |
    PWM output +------+  R  +-----|   PNP           |
               |      +-----+     |\                |
---------------+                    \       L       |
                                     ----UUUUUUU----+------>
                                                   _|_
                                                   ___ C     output
                                                    |
                                               GND--+------>


2. A regulation of the RPM of a small dc motor. I thought of using the
pwm feature of one ccp module to generate a pwm signal that
drives the motor (buffered with a transistor) and use the capture
feature of the other ccp module to measure the RPM with some kind of
optical sensor.

In both cases I would like to have a resolution of about 6 bits if
possible. The changes in voltage and RPM won't be faster than 1s for
0%-100% or 100%->0%.

I guess that somebody has done something similar already. I would
appretiate any ideas/corrections/code fracments/schematics.

--
Stefan Bormann  s.bormann@tu-bs.de

http://www.stud.uni-hannover.de/~toci/stefan_d.htm