My apologies! Here are more details about what I'm trying to do...
I have a small, dimmable LED lamp which I've been using as a flashlight for my work. It's USB powered and I power it with a small power bank. (I don't have current or voltage specs to hand, sorry.)
The lamp works perfectly for me, but the dimming controls are painfully slow and hard to use. You have to keep your finger held on one button and wait ages while the brightness slowly goes up, then another button to dim down again.
I'd like to be able to quickly adjust the brightness with just a simple movement of the finger or thumb, so I can find just the right brightness at any given moment. So I'd like some kind of analog controller - like a slider or trigger.
If anyone is willing to take a look at the LED and see what they think, I could send it out with return postage at no cost to you.