Are heatsinks required for voltage regulators?

[pingosimon]

I assume if they were required, they would be included in kits and the build instructions, but how heavily are they recommended? The 7809 regulators on my MB-6582s are so hot that I can't keep my finger on them for more than a second or two.

[lylehaze]

The amount of heat they put out depends on how much current your project is pulling, multiplied by the difference between the input and output voltage of each regulator.

OK, so who cares bout the math? My point is that a wallwart with a higher voltage will result in more heat.. so the original designer has NO WAY of predicting how much heat your regulators will put out, unless they provided your wall wart in the kit.

How hot is too hot? The regulators will shut down if they get too hot. So you don't need to worry about damaging anything..

But if they shut down in the middle of your live concert, you'll be embarrased.

Getting the temp down to "safe to touch" is a good idea if you have room for heatsinks. You can buy "fancy" heatsinks or use any spare scraps of metal.

The positive regulators that have the center pin grounded also have the tabs grounded, so they can use your metal case as a cheap heatsink. Negative regulators, and "stacked" regulators have their tab at some voltage, so you'll need to keep them isolated from the case, either by using unattached heatsinks or insulator kits (often mylar).

Have Fun,

LyleHaze

[Wilba]

If you're using PSU option A, a single heatsink is easy to fit.

I use a small one with fins, you can see it here:

I didn't use one on my original MB-6582, it didn't seem to get hot so I didn't bother... this became a lack of any instructions to use one in the build guide, and lack of one in the parts list.

If you're using PSU option B, I do mention heatsink use in the guide:

V1 cannot share the same heatsink with V2 and V3, as the heatsink mounts are connected to the common pin and V1 common pin is connected to 5V, V2 and V3 common pins are connected to ground

If you can find small U-shape ones that can mount on either side of the regulator, i.e. so the metal side of the regulator goes inside the U, then you can fit three of these to the three regulators... there's one like I suggest in the sammichSID kit on its way to you now :D