heat transfer of MOSFET to heatsink

[jdg123]

Please help me beat the heat for my first Pass Labs DIY...

In the BOM for Aleph J there is no mention of a paste or pad for attaching items to heatsinks. I just need a recommendation please.

Thanks!

 

[Zen Mod]

search for "mica and goop" thread

no need for beating a dead horse

 

[KatieandDad]

Mica or silicon insulator and "goop" which is thermal transfer compound - otherwise known as white s**t. If you opt for the grey soft insulator you wont need any goop.

 

[6L6]

The DIYaudio store sells red Keratherm in the proper size - these are the amongst best available goop-less insulators you can get.

10 Keratherm® Red Insulators - Parts

If you don't want to wait, you need a pad designed for TO-247 and/or TO-3P package fets, and are looking for a low thermal impedance.

The search engines at Mouser and Digi-key both have a fantastically hard time with this...
So here you are - http://www.mouser.com/ProductDetail...GAEpiMZZMsiS1%2bJOF5Pn2P0yVmFGVa0aI9mlusI07Y=

This is the new Bergquist A2000 material, which looks to be incredible good.

 

[jdg123]

great help!

Thank you for the excellent pointers!!!

 

[KatieandDad]

Please do read up on "goop". It's not there to help the thermal transfer, well not in massive quantities anyway. The aim is to get the "devices" to sit as flat as possible on the heatsink so that heat can flow. If the MOSFET was PERFECTLY flat and the heatsink was PERFECTLY flat there would be no requirement for goop. In reality the two mounting surfaces are anything but flat. The goop is only there to fill in the irregularities between the two surfaces.

 

[Triodethom]

A sheet of glass and some 2000 grit paper to polish the surfaces are how cpu get mated to heat sinks and then they still use silver goop. Well at least the hard core ones do this for heat transfer.

 

[Triodethom]

The DIYaudio store sells red Keratherm in the proper size - these are the amongst best available goop-less insulators you can get.

10 Keratherm® Red Insulators - Parts

If you don't want to wait, you need a pad designed for TO-247 and/or TO-3P package fets, and are looking for a low thermal impedance.

The search engines at Mouser and Digi-key both have a fantastically hard time with this...
So here you are - http://www.mouser.com/ProductDetail...GAEpiMZZMsiS1%2bJOF5Pn2P0yVmFGVa0aI9mlusI07Y=

This is the new Bergquist A2000 material, which looks to be incredible good.

How about the
SPA2000-0.015-00-58 it about 1/2 the price .

 

[6L6]

It's too small for a TO-247.

Why are you speaking so largely?

 

[Triodethom]

It's too small for a TO-247.

Why are you speaking so largely?

Sorry about that it the past and copy I used did not mean to be rude.

 

[6L6]

I know you didn't mean anything by it... Just trying to keep a bit of humor going.

 

[Triodethom]

I got old so some time I need to speak up to hear my self.

 

[Einric]

I used THESE for my F4 and they work great.
There is very good thermal coupling without goop.
I used 6-32 screws and a fender washer for mounting.