On Fri, 16 Jun 1995, BOWDEN, ANDREW V JR wrote:

>      I'm interested in controlling a 90-volt, 2.4 amp DC motor with a PIC
>      using PWM. This is not a servo application, just simple but precise
>      speed control in one direction with braking.
>
>      Second, can anyone suggest a proper interface circuit that will allow
>      the PIC to perform PWM. In other words, perhaps control of a MOSFET
>      that does the switching with proper protection for the PIC.

I have already work on a project like that (controlling a 110V/2.8A DC
motor using PWM, but i used a PC instead of the PIC).

For the interface circuit of the H-Bridge, i used a high voltage
bridge driver from International Rectifier IR2110 (a monolithic high
voltage and high speed dual driver with independent floating rail high
side and fixed rail low side referenced output chanels). And instead of
MOSFETs I used four IGBTs (Insulated Gate Bipolar Transistors) again from
International Rectifier the IRGBC20S (600V/19A).

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        Mavrogeorgiadis Athanassios

     ARISTOTLE UNIVERSITY OF THESSALONIKI
            SCHOOL OF ENGINEERING

     Department of Electrical Engineering
      Electronics and Computing Section
            Thessaloniki Greece
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