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help with dimming leds Answered

I recently bought an rgb 12v led tape thats about 1 meter long and i want to attach it the bottom of my scooter. What would be the best way to put a dimmer on the leds? Do i need a PWM sort of a thing or can i just use a 100ohms pot?


LEDs don't "dim" the way incandescent lights dim. They have a threshold voltage -- below that voltage they're off, and above it they're on. As you've indicated, you need a PWM or similar "chopped" power supply, so that the voltage can be raised and lowered fast enough to reduce the total light output, but prevent "flicker". You could build a PWM yourself, based on a 555 timer chip (and use a pot to vary the timing), or you could buy a prepackaged one.

a pot can do if its ok to have jump from 0 to some minimum brightness. just use a high resistance pot - the highr the better

U could just use a potentiometer, but you have to make sure that the potentiometer can handle the wattage.