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GriffinRU · 05.22.2006, 06:41 PM

It is bad, but not as bad as you all think...
Yes, performance goes down, but the higher the temperature of the FET - less current goes through this FET. So, FET's with better heatsinking will do the most job, but overall number of FET's will take care of high current spikes, when they cool.
TO-220 and simular are old design, there are better new gen FET's which offer 10+ times better internal resistance. Sooner or later they will be here as well.

If you have 2 layer PCB with power FET's then assume half of the cold current ratings when temperature of ESC goes up. If you have 3 then 1/3...
Otherwise look for smoke.

Artur

P.S. It is better then no grease at all. And if you compare 0.1 mm of termogrease with plastic case of SOIC package, it won't look so bad.

	(#27)
GriffinRU RC-Monster Aluminum Offline Posts: 748 Join Date: Oct 2005	05.22.2006, 06:41 PM It is bad, but not as bad as you all think... Yes, performance goes down, but the higher the temperature of the FET - less current goes through this FET. So, FET's with better heatsinking will do the most job, but overall number of FET's will take care of high current spikes, when they cool. TO-220 and simular are old design, there are better new gen FET's which offer 10+ times better internal resistance. Sooner or later they will be here as well. If you have 2 layer PCB with power FET's then assume half of the cold current ratings when temperature of ESC goes up. If you have 3 then 1/3... Otherwise look for smoke. Artur P.S. It is better then no grease at all. And if you compare 0.1 mm of termogrease with plastic case of SOIC package, it won't look so bad.