View Single Post
  #37   Spotlight this post!  
Unread 04-05-2012, 12:19
techhelpbb's Avatar
techhelpbb techhelpbb is offline
Registered User
FRC #0011 (MORT - Team 11)
Team Role: Mentor
 
Join Date: Nov 2010
Rookie Year: 1997
Location: New Jersey
Posts: 1,624
techhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond repute
Re: Non-FRC Motor Controller?

Quote:
Originally Posted by rbmj View Post
Then what are those zener diodes for (assuming I'm identifying them correctly)? Just in case there's a switching delay that isn't supposed to happen the MOSFETs don't get fried?
I think you mean the body diodes of the MOSFETs.
Those are part of the MOSFET and allow current that would reverse the polarity of the MOSFET transistor itself to flow past it instead.

Many other details applicable to the circuit apply. Such as field collapse in the motor. Heating of those diodes. Synchronous rectification. I'd read the text on it.

Quote:
And then I can infer there's an oscillator that drives a clock for the whole thing? And the PWM signal is somehow fed into this oscillator that changes the frequency (and forward/reverse)?
The Jaguar contains a Stellaris microcontroller. Think small computer. The signals go into the Stellaris. The Stellaris requires an oscillator like most computers. The Stellaris processes the inputs and outputs and produces a new signal that it's programmed to produce from each input that it encounters (sometimes based on additional inputs and outputs as well).