Thread: Modeling motor control
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Unread 07-01-2011, 15:23
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Re: Modeling motor control
Quote:
Originally Posted by Kevin Sevcik View Post
Both Jags hold one half of the h-bridge constant. So in forward motion, the M- half is held high-OFF, low-ON for the entire PWM cycle. In the Tan Jags, the M+ high side is selected via the PWM pin, and the output disable is modulated, so the M+ low side would never turn on. So that's a Forward-Open modulation. The Black Jags do things differently and alternately drive the M+ high and low sides. That's a Forward-Shorted modulation, because we never turn on the M- high side.
Just to clarify, even with "Forward-Open", the Tan Jag still has a path for the current through the Q4,5,&6 Zener diodes.