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I'm designing an enclosure for a device with mains voltage power mosfet devices.

First I thought about using TO-220 MOSFETs, and mount them up against the aluminium enclosure. However, screwing them to the heat sink using the TO-220 package tab hole seemed unnecessarily difficult, what with the tab being conductive and all. So instead I opted to clamp them to the enclosure.

However, now that I'm thinking about it, if I'm not going to use the hole, why can't I just use a TO-262 package instead?

I googled a bit, but couldn't (in a few minutes) find an example of anyone using a TO-262 clamped to a heatsink.

Is there any reason not use a TO-262 vertically mounted, clamped to a heatsink/enclosure?

Edit: Forgot to say that I need the mounting to have at least basic isolation between all the TO-262 terminals and the enclosure/heat sink.

avl_sweden
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    The tab on a TO-262 is just as conductive as the one on a TO-220. – Ignacio Vazquez-Abrams Sep 28 '15 at 06:59
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    fyi: There are [TO-220 mounting kits](http://electronics.stackexchange.com/a/26763) (also [this](http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_34121_-1)) that take care of insulating the TO-220's tab from the heatsink. – Nick Alexeev Sep 28 '15 at 07:02
  • Yeah, I know about the mounting kits. I think they can't provide enough creepage distance for basic isolation. – avl_sweden Sep 28 '15 at 07:16
  • @NickAlexeev: You should probably read his previous question (http://electronics.stackexchange.com/questions/192375/using-aluminium-enclosure-as-heat-sink). Also, avl_sweden, you should probably add to this question that you want IEC-60950-1 conformity etc. Just functional isolation is easy to achieve. – Fizz Sep 28 '15 at 07:18
  • I'm beginning to think my quesiton might be a little silly. Of course you can mount the TO-262 against a heatsink. It's not magic. I'm just wondering if there might be some snag that I'm not aware of. – avl_sweden Sep 28 '15 at 07:22
  • It should be noted that the tab on the TO-220F is isolated. – user4574 Apr 18 '17 at 12:36

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Is there any reason not use a TO-262 vertically mounted, clamped to a heatsink/enclosure?

Assuming you're not confusing TO-262 (aka I2PAK) with the much more common TO-263 (aka D2PAK or DDPAK), no there's no reason. In fact TO-262 is the vertical mount version, though-hole mount (unlike TO-263 which is surface), straight-leads.

Fizz
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    Because of the relative obscurity of the package, it's a hard to find detailed mouning instructions/guidelines for TO-262. You should probably just refer to TO-220 clip mounting instructions... See [this guide](http://www.infineon.com/dgdl/Processing_TO.pdf?fileId=db3a30431936bc4b011938532f885a38) for example, where TO-262 at least gets a passing mention. – Fizz Sep 28 '15 at 08:13
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    @avl_sweden: also in [Infineon AN 2012-10](http://www.infineon.com/dgdl/Infineon+-+Application+Note+-+PowerMOSFETs+-+CoolMOS%E2%84%A2+-+Electrical+Safety+and+Isolation+in+high+voltage+Applications.pdf?fileId=db3a30433d1d0bbe013d20e0cbf017fe) it is said that plastic-bodied clips exist for HV mounting, but the image there is less than clarifying... – Fizz Sep 28 '15 at 08:38