Led strips on dimmer??

Luke_Bowman · 4 Aug 2012 at 11:28

So I have some spare LED strip left and I have an idea for my next little project. Would it be possible to power this 12V strip from a fan controller and dim then to suit my mood/game etc?

Thank in advance Overclockers

Unicorn · 4 Aug 2012 at 11:46

I couldnt see why not aslong as your connectors are correct or you are handy with a soldering iron.

d_brennen · 4 Aug 2012 at 11:50

LED brightness falls off very fast with voltage drop. You'd probably be better dimming them using PWM duty cycle timing

Tealc · 4 Aug 2012 at 12:11

D_brennen is right. You wont get more than a couple of Volta below supply before the LEDs will just shut off.

What about hooking up your LEDs to your PWM CPU fan output? Get brighter with temperature, dimmer with cooler temperatures.

Roverno · 4 Aug 2012 at 14:11

It does work just fine actually. I got a couple of strips hooked up to my 600T controller. Just change the connector from Molex to 3pin fan and plug them in. You get a very good range of brightness so works well imo.

Tealc · 4 Aug 2012 at 17:10

Roverno said:
It does work just fine actually. I got a couple of strips hooked up to my 600T controller. Just change the connector from Molex to 3pin fan and plug them in. You get a very good range of brightness so works well imo.

It works fine in your case.

Some LED strips have resistors in series with the three or more LEDs and with say white or blue colour LEDs you'd have maybe 2 Volts tops adjustment, assuming your fan controller can even output 12v. At too low a voltage (around 9-10v) the LEDs would just go out

Other LED strips have a single resistor per single LED and you can get good adjustment with a fan controller right down to 3 or 4V input but most LED strips are not contructed in this way as it can waste energy.