LT1083 PS-regulator for class A amps

[bogdan_borko]

This is the power supply regulator I made for my class-a "Krypton" amplifier and it works great!

Ripple before regulator is 1V and afer regulator 100uV with the 2A load!

Sounds great to.


Note: Regulators must be matched, or you have to connect balast resistors on the regulators output(0.1 Ohm is enough).

[bogdan_borko]

This is a module :

[FYC]

Interesting, when you say matched, what are you matching, and what is the tolerance you are looking for?

[bogdan_borko]

They are matched for an output current for the same reference on the adj. pin.
Both regulators I use are from the same production series (same serial number) and they have the same currents, without the balast resistors.

[hifimaker]

I assume that the 1N4004 diodes around the regulators are for protection? Interesting that it looks like a half wave rectification. I'll need to do some more research on the regulator part.

-David

[anatech]

Hi bogdan,
You should always use ballast resistors when paralleling regulators (or transistors). Matching them only is poor practice without using ballast resistors.

At least you have used reverse breakdown protection. This is very wise.

-Chris

[jleaman]

This might work great for the Aleph Mini's, wonder if it would improve any thing tho.

[anatech]

Hi Jason,
I think the input - output voltage is far too close. It will probably drop out when the line voltage drops a little. I don't know what the line regulation is like in Europe where Bogdan is, but here in North America the line variation is too high for this circuit. Add to the fact that the step down ratio is 1/2 what Bogdan's transformer is ...

Nope.

How much current does each channel draw?

-Chris

[jleaman]

Originally posted by anatech
Hi Jason,
I think the input - output voltage is far too close. It will probably drop out when the line voltage drops a little. I don't know what the line regulation is like in Europe where Bogdan is, but here in North America the line variation is too high for this circuit. Add to the fact that the step down ratio is 1/2 what Bogdan's transformer is ...

Nope.

How much current does each channel draw?

-Chris

depends on the bias, i think mine are all set at 1amp per channel.

[anatech]

Hi Jason,
Okay, your dissipation will be that current times the voltage drop. I imagine you want one regulator per channel.

Measure your highest AC voltage and your lowest. Add the dropout voltage and some safety factor plus the ripple trough. This will be your worst case voltage drop. Multiply that by the current and this is how much heat you have to get rid of.

-Chris