Practical use of 431 regulator

[borges]

Hi,

I need two DC reference voltages adjustable between +5V and -5V. The easiest way to do this, I figure, is to use a couple of 431's and follower opamps.

The data sheets for the 431 feature wildly varying feedback resistors in the different examples. So I'm seraching for schematics with successful use of 431. It would help me if you could link to old posts with 431's in them.

I'm not limited to this reference, so if there are circuits that are more fit than the 431, I'm open to that.

The figure shows how I planned to use the regulators. There will be decoupling capacitors on the power supply pins and possibly where I tap the potentiometers. Should there be decoupling elsewhere too?

Greetings,

Børge

[borges]

Trying attach once more...

[peranders]

I suggest that you choose 1 k for gain setting also. I have 1-2.2 k between ref and GND. Don't forget to consult the datasheet also. Notice that different brands are different, not exactly second source.

Consult the datasheet concerning caps for the 431. 0-10 nF or > 10 uF. It's normallay not necessary. Just ad a LP-filter between the pot and opamp input. 100 k + 0.1-1 uF or something.