If you are interested in the exact cause of the MOSFET failure, take a look at this Web page:
http://www.4qd.co.uk/serv/MOSFETfail.html
Especially look under the section entitled dV/dt failure--it probably describes your situation perfectly.
Also, while most MOSFETs fail open, occasionally one can fail shorted, which would apply continuous power to your motor. Because the motor was not drawing enough current to either burn out the shorted MOSFET or trip the circuit breaker, the motor continued to operate.
Eldarion
__________________
CMUCam not working? Tracks sporadically? Try this instead:
http://www.falconir.com!
PM me for more information if you are interested (it's open source!).
Want the FIRST Email blasts? See here:
http://www.chiefdelphi.com/forums/sh...ad.php?t=50809
"The harder the conflict, the more glorious the triumph. What we obtain too cheaply, we esteem too lightly; it is dearness only that gives everything its value."
-- Thomas Paine
If it's falling apart it's a mechanical problem. If it's spewing smoke it's a electrical problem.
If it's rampaging around destroying things it's a programming problem.
"All technology is run on 'Magic Smoke' contained within the device. As everyone knows, whenever the magic smoke is released, the device ceases to function."
-- Anonymous
I currently speak: English, some German, Verilog, x86 and 8051 Assembler, C, C++, VB, VB.NET, ASP, PHP, HTML, UNIX and SQL 
It's your duty in FRC to your teammates and alliance partners to put the most competitive robot possible on the field. - Chris is me [more] 
07-02-2008, 02:52
Similar Threads
Threaded Mode