Amp mosfet thermal tape?

[rgsgww]

The mosfets on my amp need to be electrically insulated from the heatsink. I have no insulating thermal tape. Would electrical tape or a piece of think plastic be good? Just cant find the proper tape.

[Wizard]

Re: Amp mosfet thermal tape?

Need to be thermal conductive and electrically insulative.

Try your electronic service shops that really repairs down to the component level and see if they do have some in their stock.

Cheers, Wizard

[rgsgww]

Re: Amp mosfet thermal tape?

Thats what I thought. Those things are not very thermally conductive. The original insulators crumbled.

I will look for tape or pads. I have found some places on the net

[rgsgww]

Re: Amp mosfet thermal tape?

This should work for me, what do you think?

http://www.rapidonline.com/Electroni...tive-pad/77135

[Wizard]

Re: Amp mosfet thermal tape?

Yes like that.

It comes in stamped forms for certain types of transistor packages or sheet that you can cut with knife or scissors.

Size the pad oversize a bit around the transistor you are using. Mica available as well (have to use heatsink compound on both sides of mica).

Cheers, Wizard

[rgsgww]

Re: Amp mosfet thermal tape?

Alright, it should be better than the old caked on thermal paste. Wasn't as bad as my mobo's. That stuff was like dust.

[larrymoencurly]

Re: Amp mosfet thermal tape?

Those insulators are made from either mica (rigid, clear), kapton (transparent brown plastic), or silicone rubber (grey, red, blue). I believe that thermal grease is supposed to be used with the mica and kapton insulators but isn't always necessary with the silicone rubber ones. You should be able to get some from an old CRT monitor or PC power supply.

[Wizard]

Re: Amp mosfet thermal tape?

kapton (transparent brown plastic) is not thermal conductive.

Plain rubber or plain silicone sheets are also not thermal conductive either.

You need the mica insulator (use thermal grease) or flexible thermal pads (less messy).

The thermal pads are specially made for insulating and thermal conduction.

Cheers, Wizard

[Krankshaft]

Re: Amp mosfet thermal tape?

Don't forget to isolate the mounting screw too or all of this will go to waste.

A plastic washer will suffice.

This is why I like 100% plastic encased transistors for this the mounting tab and the metal back is covered in plastic.

No isolation material is needed just put the thermal paste on and install.