JRC 7815 Regulator

[TomCarlos]

Team MEF...

I found a stash of JRC 7815 Regulators. I noticed there is no metal on the back side. So I am wondering if these were intended to use in low power applications or can you in fact use them with a heat sink? For reference, I am also showing a sample of a 7815 that does have the metal exposed on the TO-220.

Thanks in advance.

[mhuss]

The 'insulated back' ones are to make isolation from ground easier. These can still be heat-sinked, but tend to have poorer heat conduction characteristics then their metal-backed cousins, so can dissipate less heat for a given heat sink.

[Helmholtz]

It is a TO-220F or TO-220FP package, F meaning fully isolated.
The metal tab is encapsulated within the case.
For thermal considerations find the datasheet.

https://en.wikipedia.org/wiki/TO-220

[g1]

As far as I know, the metal is inside and fully encapsulated. It saves from having to use insulator as mentioned above.

[TomCarlos]

Thanks mates.... this was very helpful.

I am asking because of the Bugera amp I am working on. You'll see an update to that post in the next few days. But for reference, there could be an issue with the 7815 overheating. In that amp, it uses this "F" type package that Helmholtz mentions. The 7815 is mounted in very close proximity to a 7915 leaving very little room to utilize a heatsink. I cannot confirm at this point in time, but it may be that the 7815 is getting hot (and wearing out after years of usage) and causing issues.

Again, my appreciation for you taking the time to reply.

[Helmholtz]

but it may be that the 7815 is getting hot (and wearing out after years of usage) and causing issues.

Does it get too hot to touch? Would mean over 50°C/ 60°C
In that case you might epoxy or screw on small aluminum plates.

Or post a pic of the board for more ideas.

[TomCarlos]

I will carry this conversation over to the Bugera post I started previously. But in closing on this thread, here is a photo of the two regulators.

The 7815 is on the left. It is hard to see but the Regulator is leaning up against the Input board (Input jack, tone controls, etc). If I could remove the input board temporarily, I could try bending the Regulator down and adding a small heatsink, maybe something like the one shown in the photo - or maybe I have to cut off some metal to make it fit.

I will power up the amp and try to use my infrared thermometer and a touch test if I am brave enough to stick my finger in there !!