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GriffinRU · 05.22.2006, 07:31 PM

There is one big problem with small FET's...
As long as we are familiar with FET's behavior under high temperature, there is one component which still acts as old transistor. It is built in diode, which protect FET, but in TO-220 package it is serious diode while in SOIC tiny one and not matched to the rest of the diodes. So when it goes it either short or opens, in first case meltdown in second delayed eventual meltdown.
Solution - serious diodes 6 way H-bridge on the motor leads with output directly to the battery. You will be impressed how much heat you will take from ESC.

Artur

P.S. Good low voltage drop high-current diodes.

	(#32)
GriffinRU RC-Monster Aluminum Offline Posts: 748 Join Date: Oct 2005	05.22.2006, 07:31 PM There is one big problem with small FET's... As long as we are familiar with FET's behavior under high temperature, there is one component which still acts as old transistor. It is built in diode, which protect FET, but in TO-220 package it is serious diode while in SOIC tiny one and not matched to the rest of the diodes. So when it goes it either short or opens, in first case meltdown in second delayed eventual meltdown. Solution - serious diodes 6 way H-bridge on the motor leads with output directly to the battery. You will be impressed how much heat you will take from ESC. Artur P.S. Good low voltage drop high-current diodes.