Heatsinks
Shaun, Thu Jun 21 2007, 05:43PMI'm working on a medium size DRSSTC, and so far I have all the larger parts assembled, such as the secondary, primary, base, etc. Most of the drive circuit and interrupter is also complete.
However, I don't have any proper heatsinks for my IGBTs. I'm using a half-bridge of HGT1N40N60A4Ds, only because I cannot find any more of them for a reasonable price.
I know people like to use bigass heatsinks for these, and I only have a few small ones from a computer monitor. I was looking through some sites and I cant find any sink designed for the SOT-227B package. Can anyone help me with this, maybe with model numbers they have used? As I said I only have 2 and at $25+ each I want to take all the precautions I can, so bigger is better.
Re: Heatsinks
Steve Ward, Thu Jun 21 2007, 05:56PM
They dont make heatsinks specifically for these IGBTs. Just check up on ebay for slabs of heatsink. A fan can also go a long way in keeping things cool.
Steve Ward, Thu Jun 21 2007, 05:56PM
They dont make heatsinks specifically for these IGBTs. Just check up on ebay for slabs of heatsink. A fan can also go a long way in keeping things cool.
Re: Heatsinks
Shaun, Thu Jun 21 2007, 06:06PM
Thanks alot Steve. It does seem to be a bit of an obscure package. That nagging voice in my head kept saying i'd end up drilling holes in a large secondhand sink not meant for this IGBT. I have 2 spare 12 volt computer fans I'll use, so that should help.
How important is using a thermal paste between the IGBT and the heatsink? Because I don't have any of that.
Shaun, Thu Jun 21 2007, 06:06PM
Thanks alot Steve. It does seem to be a bit of an obscure package. That nagging voice in my head kept saying i'd end up drilling holes in a large secondhand sink not meant for this IGBT. I have 2 spare 12 volt computer fans I'll use, so that should help.
How important is using a thermal paste between the IGBT and the heatsink? Because I don't have any of that.
Re: Heatsinks
..., Thu Jun 21 2007, 06:18PM
It is very important if you are running at high powers.
I don't even look for heatsinks made for a particular package, I just find whatever I have laying around and tap some #4-40 holes in it.
..., Thu Jun 21 2007, 06:18PM
It is very important if you are running at high powers.
I don't even look for heatsinks made for a particular package, I just find whatever I have laying around and tap some #4-40 holes in it.
Re: Heatsinks
Josh Johnson, Thu Jun 21 2007, 07:16PM
Packages like these with the isolated mounting plates are made for a big heat sink. In power electronics applications usually there are a lot of necessary components that need a heat sink like rectifiers, diodes, scrs, and IGBTs. With this sort of mounting scheme you can get all the parts on one common heat sink.
Thermal paste is as important as the heat sink.
Check out this site: http://www.techpowerup.com/printarticle.php?id=134
Josh Johnson, Thu Jun 21 2007, 07:16PM
Packages like these with the isolated mounting plates are made for a big heat sink. In power electronics applications usually there are a lot of necessary components that need a heat sink like rectifiers, diodes, scrs, and IGBTs. With this sort of mounting scheme you can get all the parts on one common heat sink.
Thermal paste is as important as the heat sink.
Check out this site: http://www.techpowerup.com/printarticle.php?id=134
Re: Heatsinks
Steve Ward, Fri Jun 22 2007, 12:15AM
Just a detail, but for these IGBTs you want a #6-32 screw to hold them down (not a #4-40). #8 doesnt fit through the holes.
Steve Ward, Fri Jun 22 2007, 12:15AM
Just a detail, but for these IGBTs you want a #6-32 screw to hold them down (not a #4-40). #8 doesnt fit through the holes.
Re: Heatsinks
thedatastream, Fri Jun 22 2007, 07:40AM
Smaller heatsink + fan can rival the performance of a larger heatsink. CPU coolers, which are designed for forced air cooling (thin fins, lots of them) can handle large amounts of power similar to that you would expect to see in a DRSSTC IGBT.
I've used CPU heatsinks and fans on my (as yet untested) DRSSTC
thedatastream, Fri Jun 22 2007, 07:40AM
Smaller heatsink + fan can rival the performance of a larger heatsink. CPU coolers, which are designed for forced air cooling (thin fins, lots of them) can handle large amounts of power similar to that you would expect to see in a DRSSTC IGBT.
I've used CPU heatsinks and fans on my (as yet untested) DRSSTC
Print this page