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12v DC LED Light with 18 Superflux LEDs

I have just completed a 12V DC based LED light which uses 18 Superflux (four legged/ Piranha) LEDs. These LEDs have capabilty of taking currents upto 70mA. I have divided them into 6 strings of 3 LEDs each.

Each string is driven by a constant current source. This was the reliability is improved and we can use simple transistors to create the constant current source.

By default I drive the LEDs at around 34mA.

There are 4 Amber/Yellow LEDs which I use and these are put in place so that the light will work even if the battery voltage drops to below 10.5 Volts (albeit with reduced brightness).

I have just put up these on ebay for sale. And some have asked me to supply these with all white LEDs. I have obliged but would prefer to sell them with the 4 Amber/yellow LEDs.

Here are the pictures

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