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Unread 21-01-2014, 00:13
Dale(294engr]'s Avatar
Dale(294engr] Dale(294engr] is offline
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FRC #0294 (Beach Cities Robotics)
Team Role: Engineer
 
Join Date: Jan 2004
Rookie Year: 1998
Location: Redondo Beach, CA
Posts: 92
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Re: pic: Someone tell me what THIS is!

Quote:
Originally Posted by mman1506 View Post
Its a talon with a blown transistor
I agree.. Q12 leads (4) appear to have experienced high heat surge i.e. they are discolored.
& is likely one of the 4 bridge FETs (H-bridge power switch between input power & motor load)

often the result of a drain-source overvoltage spike "punch thru" which puts the battery across the switch without current limiting.. strange thing is 2nd FET does not appeared to have the same damage - as one is tied to +12 other to ground return (-)

The big cap looks fine.. debris on it appears to be adhesive or pealed conformal coating
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