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JBrock

5W voltage-controller LED Current Driver

Here is a voltage-controlled LED current driver for those who are not afraid to burn some POWER! Fo

  1. JBrock
    Here is a voltage-controlled LED current driver for those who are not afraid to burn some POWER! Forget those wussy switching things trying to achieve, what?, 85% efficiency maybe? What a hassle.
    This driver is for a one-LED project. The LED is a 5-Watt royal-blue Luxeon Star. It cost $40 a couple years ago but you can get good Chinese counterfeits on eBay now for about ten. This device is a classified as a Class 2 laser - "Do not look directly at The Star!"
    What can you do with one LED? The range of output is so great, that this LED is operated in analog mode. A voltage between 1 and 10 VDC is applied to the input of the driver to get a proportional percentage of The Star's output.
    A controller generates eight different waveforms which run continuously. Lines from a pseudo-random linear feedback shift register choose which waveform is selected by the 4051 analog switch.
    The current waveforms are shown, but their schematics are not revealed - yet. Only a hint - the waveforms are all generated using only 555 timers, 324 op-amps, or 3900 Norton amplifiers. I would like to see some good guesses as to how these waveforms may have been generated. If the results are worthy, I will post the solutions that were actually built and used to animate The Star of Captain Brock's BlueLight Box.