High precision output voltage regulator in the series LM317

Hello Umesh,

Take a look at the datasheet for the REF2025. It's a voltage reference providing a reference voltage output of +2.5 V, and VBIAS output of +1.25 V. Both outputs are capable of an output current level as high as +/-20 mA. It provides high initial voltage accuracy and low drift across temperature:

Regards, Thomas

PA - Linear Applications Engineering

Umesh,

Is the load floating or terminated to a known voltage. What is the voltage?

Thank you THOMAS ..I have gone through REF2025. It is very good IC. But it is costly than LM317. So I have to go for discrete circuit than IC form

Thanks

Hello Ron,
My load is actually Grounded but due to different ground used in my design, there is voltage added to the ground terminal and it is up to +/-2V.

Thanks

Umesh,

I was thinking about this topology.

Error sources are TL431 tolerance, R1 tolerance, OP_AMP VIO, PNP Beta.

Headroom requirement is 2.5V ( I can reduce to 1.25V at a little higher cost)

PMOS could replace PNP.

What is the absolute tolerant allowed system to system and from min to max resistance / ground shift?

Do you have flexibility in supply voltage?

Hello Ronald ,
I have tried Howland current source not this. I will try for this also.
My supply was variable from 8V to 32V DC. But now I am thinking make either 12V or 24V DC constant using Buck Boost. And allowable tolerance in output current should be up to 25uA.

Regards
Umesh