Sean Meighan

Hardware => General hardware => Topic started by: dridas on February 22, 2021, 07:16:50 PM

Title: Moving Head LED conversion help
Post by: dridas on February 22, 2021, 07:16:50 PM
I have a Moving Head LED that I want to convert the 3.3v LED to a 12V diffused LED.

I'm all for modifying, and testing out. It's a U'king LED moving head. The 3.3v LED is 4 separate bulbs, with 8 leads. R+,B+,G+,W+, and individual negatives (-), that are all tied together. The LED I want to replace it with has the following voltage ranges (forward biasing voltage):

R - 6v to 8v
G,B,W - 9-12v.

As I understand it, the voltage determines the intensity of the bulb. Current LED is either 3 or 4 watt.  There is a fan and a heatsink to mount to.  So, at first, I thought the obvious choice was to use a Buck Boost Converter, but I fear that will only boost the voltage to a preset value, so I'll lose the intensity. So, I thought about an optocoupler, and then providing the 6-12v power on the other side, but I don't think that will work either. Op-Amp?

I don't know what to use, but would like to possibly collaborate on it, and possible find a solution for the moving head that gets rid of the square light projection.

4 input wires carrying 2.2-3.3v to drive the current LED, and want to switch it to a 12V LED driver. This will allow the LED to continue to be controlled via the E1.31 to DMX controller I have installed.
Title: Re: Moving Head LED conversion help
Post by: bwinter on February 22, 2021, 07:24:20 PM
CURRENT is the primary concern for driving LEDs (and what controls the brightness) not VOLTAGE.  You'll need a constant-current driver, and/or one that allows you to control the CURRENT.
Title: Re: Moving Head LED conversion help
Post by: dridas on February 23, 2021, 09:43:19 AM
Quote from: bwinter on February 22, 2021, 07:24:20 PM
CURRENT is the primary concern for driving LEDs (and what controls the brightness) not VOLTAGE.  You'll need a constant-current driver, and/or one that allows you to control the CURRENT.

Any idea the parts I need to buy to do it?
Title: Re: Moving Head LED conversion help
Post by: bwinter on February 24, 2021, 07:07:18 PM
Quote from: dridas on February 23, 2021, 09:43:19 AM
Any idea the parts I need to buy to do it?

You'll basically need a constant-current LED driver, likely one that is WS281x controllable.  Similar to what I just posted here:

https://diychristmas.org/vb5/forum/hardware-software/developers-hw-sw/11138- (https://diychristmas.org/vb5/forum/hardware-software/developers-hw-sw/11138-)