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LEDS driver

DC CAFC
  • US 7,262,559 B2
  • Filed: 12/11/2003
  • Issued: 08/28/2007
  • Est. Priority Date: 12/19/2002
  • Status: Expired due to Term
First Claim
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1. A power supply for an LED light source, said power supply comprising:

  • a power converter operable to provide a regulated power including a LED current and a LED voltage;

    a LED control switch operable to control a flow of the LED current through the LED light sourcewherein said LED control switch is further operable to clamp a peak of the LED current during an initial loading stage of the LED light source;

    a switch operable to establish a current path from the LED light source to said power converter when the LED current is below the peak threshold, said switch further operable to eradicate the current path when the LED current is above the peak thresholdan LED PWM dimmer operable to provide a pulse width modulation signal to said LED control switch in response to an external dim command,wherein said pulse width modulation signal has a target pulse width in response to the dim command exceeding a ramp signal, andwherein said pulse width modulation signal has a minimum pulse width in response to the ramp signal exceeding the dim command.

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