Voltage regulators for line level circuits

[HarryHaller]

LEDS

~5mA should work fine for the 10 volt reglator. I also think you could use 4 greens and 1 red LED and get about 10 volts with 1K to 2 K across the adjustment terminals. The LEDs provide better reglation and lower noise than resistors for a given adjustment current. test under close to load current and heatsink the regulators. You can also pre regulate the 5 volt regulator at 10 volts with a another regultor for better PSRR and less power dissapation.

 

[Peter Daniel]

4 greens and 1 red LED and get about 10 volts with 1K to 2 K

Harry,

Your comments are as usually right on the point.😉 Thanks.

 

[HarryHaller]

Lucky guess.....

You will get better regulation with the 1K to 2K resistor than 100 ohm.

H.H.

 

[Flemming J P]

I planing to build some regulators with tracking preregulators using lm317/337.

As far as I can understand from this thread, using diodes instead of a resistor from adjust to ground improves regulation, is this also worth the effort when using a tracking preregulator? And should go with diodes on the preregulator as well?

HarryHaller also mentions 1K to 2K resistor rather than 100 ohm (it's the resistor between output and adjust right?) does this also apply for lm317/337?

 

[dipchip]

LED based regulator

Harry,

Would this LED regulator method work well with +15V
or does the number of LEDS introduce more noise?

Thanks,
Craig Beiferman