Is there a higher voltage version of the LM317T voltage regulator?

[bigal_scorpio]

Hi to all,

I am toying with the idea of building another PSU using a transformer I pulled from an old but working high power sony video deck. The transformer is massive and has a number of taps including among others, 60v and 28v both with what I think is a common centre tap. I will try and get a couple of pictures of it in the morning and post them for confirmation that I am right.

Since that kind of voltage is available I wondered if I could utilise it fully? I realise that it is quite a high voltage to see in a variable PSU but I was thinking it could come in quite handy for certain types of testing like some amp stages and valve equipment.

Is there any simple and reliable way of doing this with reasonable parts cost and count?

Or am I just hoping for too much? Maybe this is an unusual build but since I have the transformer I just thought that it would be nice to put it to some good use and you can never have too much choice at hand.

Any thoughts or advice guys?

Al

 

[Grossel]

Hi.

What excactly are you trying to achieve?

 

[MikeMl]

The 37V? rating on the 317 is a differential between in and out. It could be used for a power supply adjustable from 30V to 60V for example; just not from 1.2V to 60V.

 

[bigal_scorpio]

Hi.

What excactly are you trying to achieve?

Hi mate, I was basically just trying to put the transformer to good use while giving myself something to build while at a loose end, I am housebound at the moment with a back injury and getting a bit bored of doing nothing.

Al

 

[crutschow]

The 37V? rating on the 317 is a differential between in and out. It could be used for a power supply adjustable from 30V to 60V for example; just not from 1.2V to 60V.

Of course it will not be short circuit protected if it is used it in that manner.

A high voltage regulator, such as the TL738 which is rated at 125V, should work. But be aware that the regulator dissipation can become very high a low output voltages.

 

[dr pepper]

You might be better googling for a 60v bench psu circuit, using op amps.
I have a vintage weir bench supply that has an output range switch, 0-30 at 2a and 0-60 at 1a, something like this might be cool with your tranny using the 2 outputs, assuming the lower voltage o/p is a higher current one which is hard to tell, the thivkness of the winding wire gives you an idea but its still only a guess.
Current limit is advisable, preferably adjustable a constant current source can be handy and so's a bench supply that wont dump 50a into your latest project when its wired wrong.

 

[pilko]

@ crutschow ---- I think that reg. is a TL783.

pilko

 

[crutschow]

@ crutschow ---- I think that reg. is a TL783.

pilko

Yup, you are correct. My dyslexia is kicking in again.

 

[WTP Pepper]

Yep used these previously. Having a heatsink lures you to thinking they can supply an amp like the 317T, however I used it for 10mA for a high voltage supply and it still got warm due to the Vin-Vout magnitude.
National Semi do some very good high input voltage switchers.