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Unread 04-07-2007, 19:15
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Generalx5 Generalx5 is offline
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Cool Re: HomeMade Motor Controllers

All I remember is that these Metal Oxide Semiconductor field effect transistors in those victors are linked together in parallel, they are high current transistors that either has an N substrate or a P substrate. PMOS or NMOS, I also know that they require something called a MOSFET Driver that delivers short bursts of high current 1- 3 amp of 5- 22 volts to the gates of the MOSFETS, these drivers can be found either inverted or non-inverted so that a +5 could either indicate MOSFET conduct or not conduct. There is a helpful guide on the IRF website that explains how to pick your MOSFET and match it with a proper MOS Driver. Its really complicated...

examples of MOSFET DRivers are the ones from Microchip.com, TC4426 (improved version of TC426), TC426. The two listed are dual drivers, they can drive 2 different signals at one time. You can also find single drivers and Quad drivers as well. These drivers tipically require about two miliamps of current in their source. Its important to have a capacitor at their drain and source terminals. The MOSFETs we see in the Victors each can handle about 20 - 30amps? (ballpark figure...maybe more) with it hooked up in parallel, they are able to source large amounts of current.

It is important that you look at the white pages on the MOSFET specific to your project, they will tell you how much current it is able to handle under what temperatures, proper air cooling with sinks may be needed. also as mentioned above, with the rise in die temp, the resistance also increases, but this shouldnt be a problem if you are using a MOSFET driver. Hope that helps.

Last edited by Generalx5 : 04-07-2007 at 19:25.