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Will this LED Driver work on 12v? (specs included)

Discussion in 'The Projects Forum' started by Justinwat, Dec 20, 2008.

  1. Justinwat

    Thread Starter Member

    Dec 15, 2008
    I am working on a 12v project using the P7 LED (2800mA). I found this driver that is made for this specific LED but it says the Max Input is 35v. It doesn't give a Min Input. Does anyone know if this will run one P7 LED off of a 12vdc battery?

    KONLUX2800 – High Power constant current source 2800 mA for operating Seoul P7 ® LEDs and similar components

    High efficiency and low heat by modern switching technology. The use of special amplifiers guarantees a precise and constant output-current. Small dimensions, low weight and high reliability through the use of SMD-technology (surface mounted components). Every HKO is electronically tested..

    Technical data KONLUX2800:
    Startup: ca. 5,1 volts (for one P7) with reverse polartiy protection
    Startup: ca. 4,7 volts (for one P7) without reverse polarity protection
    Drop: ca. 2 volts
    Maximum input voltage: 35 V DC
    Output: Short circuit protected
    Output current: 2800 mA constant
    Input: reverse polarity protected (can be passed)
    Tolerance < 3% over the complete voltage range
    Efficiency: depending on the count of LEDs and input voltage between 75 und 90 %
    Thermal protection
    Working temperature range: -40 °C to +85 °C

    To drive up to 9 P7 Leds in series with 35 volts input for maximum light power! The LEDs must be cooled, please refer to the data sheets of the manufacturer. The back side of the CCS is covered wth tinned copper, it is connected to minus input (don´t forget, when mounting the constant current source). The KONLUX 2800 must be cooled for continous operation . The printed circuit board can be easily mounted on a heat sink or metal surface with the self adhesive cooltape. Due to the high currents in the input of the circuit additional filtering may be necessary. Please check. We recommend very short cables to the power source.

    Printed circuit board:
    Dimensions: 30 mm x 31 mm, 7 mm high
    Connections: soldering pads
    Weight: approx. 5 grams
    Material: FR4
    Back side: copper, tinned, connected with - IN


    Thank you all who have helped with my previous questions.
  2. SgtWookie


    Jul 17, 2007
    Yes, it should run a single P7 just fine. If you could wire them in series, you could probably run several of the P7's, depending upon their forward voltage.

    The regulator itself has a Vf of 2v. So, 12v-2v=10v. If the P7 LEDs had a Vf of 3.33 or less, you could run three of them in series.
  3. Justinwat

    Thread Starter Member

    Dec 15, 2008
    Thank you SgtWookie! You saved the day again and helped me understand your answer.

    It's good to know that there are knowledgeable people who are willing to help out there. A rare combo.
  4. Ordibble Plop

    New Member

    Dec 21, 2008
    I've been looking into the same thing. Another couple of possibilities I found are:

    SSC P7 buck converter

    hipCC or hipFlex from TaskLED

    I haven't used any of these and am starting from a position of ignorance so can't comment on quality sorry.
  5. Justinwat

    Thread Starter Member

    Dec 15, 2008
    I just received the KONLUX2800 LED Driver. The + DC IN has 2 options: + IN without reverse-polarity protection and + IN reverse polarity protected. What would be the benefits of using the polarity protected? Which should I use? Thanks for your help.
  6. SgtWookie


    Jul 17, 2007
    From the technical specs:
    So, you'll need about 0.4v more input voltage to start the regulator with protection than without it. Since you're using 12v, that doesn't seem to be an issue.

    If there is ANY possibility that you could accidentally connect it up backwards, use the reverse polarity protection input.