Hi,
I am building a LED panel for photo studio and I want to dim panel
I have the following
DC 4.0~40 to 1.3-37V LED Voltmeter Buck Step-down Power Converter Module LM2596
10K Sliding Slider Potentiometer Module

I want to have 12v at one side and other side 9v of slider. Basically from 9v to 12v spread evenly through out the slider.

 

You need to carefully remove the existing pot and replace it with your 10k pot. (assuming that you can use an active pot in this case)

Then you need to bypass that pot with a resistor that limits the voltage to 9.

It’s tricky to get a pot to respond linearly that isn’t the proper resistance in the first place.

You could set the regulator pot at the voltage you want then measure that resistance after you remove it, and then just use a pot close to that resistance.

I wouldn’t advise using that kind of pot in this instance, just get a regular passive pot. (maybe I’m making an incorrect assumption regarding that pot, but I have never seen a pot with VCC and Ground markings)

 

Sorry, I’m always getting the adjust pins ass backwards.

This is what you need to use the 9 to 12 volt scale, I’m sorry I can’t give you the values because I don’t know what the resistor is from the output to adjust pin is. (assuming that regulator works like a linear)