Thread: upgraded FETs
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Old 04-30-2004, 04:34 PM
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Jshwaa Jshwaa is offline
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Quote:
Nice it looks like the power is more regulated
There's no regulators on that board, only FET's and resistors.

Quote:
but the smaller componets and the resistors are limiting your current.
The smaller components are FET's and the resistors prevent their drain-to-source current from frying them. Guess you'd need a circuit diagram to even know that, which puzzles me as to how you're an expert on this circuit having never seen one.

Quote:
Neuro's FET design is more effective and does not get hot at all. Warm but not hot.
That may be, but mine isn't finished yet. I highly doubt that anyone's attempts at external ESC building has conquered some of the dilemnas that it introduces. For instance, how are the gates of the FET's being driven completely on and off, when the weak signal from IC1 isn't even half as strong(voltage-wise) as what's needed to drive an FET with VGS of +-10V?

Those smaller(TO-92) FET's are what I used in an attempt at conquering that dilemna. It didn't work as well as I had anticipated. The parts that get hot are the power FET's, not the supposed current-restrictive smaller FET's and resistors. Without those parts(TO-92's and resistors) the ESC couldn't have worked as well as it did. So I'm completely puzzled as to how anyone's(Neuro's, Ph2t's, etc.) could have had produced desired results. I haven't seen any more than what's been provided on the forums, so I don't know for sure, so don't get me wrong. I'm not trying to bash anyone's enginuity or knowledge on the subject.

Quote:
Post the part numbers of the smaller transistors maybe we can fix the heat problem. Post a diagram if possible. Oh are you using logic level Fet's.
I know exactly where I went wrong and have parts on their way(by next monday,5/3) to build another one. I'm confident that the issue will be resolved and the ESC will then work at peak efficiency(200W, 74A, 20V, 0.028 RDS(on) for forward or reverse minus the motor load)
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