Hi, I recently got my hands on a dozen or so DC-DC smd stepdown regulators from aliexpress. I figured this would be a cheap and faster way of building power banks then making a bunch of l7809 circuits on vero as I normally would.
I wired them up as I expected you would. Input 12v to the In+ and Output connected to Out+ (gnd to gnd) and nothing useful appears to happen? It steps down to around 8.1v but the trimpot has seemingly no effect. Is there a trick to this? Is there something I am missing? Or is it just shoddy aliexpress chips. Ideas?