Abstract: A method for starting up an illuminating process of a plurality of series connected LEDs by means of a LED driver is described, whereby a maximum allowed voltage output of the LED driver is lower than a forward voltage of the plurality of series connected LEDs in a cold state. The method comprises: d) providing a first current, in value lower than a desired current, by the LED driver to the plurality of series connected LEDs, resulting in a forward voltage across the plurality of series connected LEDs lower than the maximum allowed voltage output of the LED driver, e) waiting during a predetermined wait time period, f) stepping up of the first current to a second current provided by the LED driver to the plurality of series connected LEDs.

Abstract: A method for starting up an illuminating process of a plurality of series connected LEDs by means of a LED driver is described, whereby a maximum allowed voltage output of the LED driver is lower than a forward voltage of the plurality of series connected LEDs in a cold state. The method comprises: d) providing a first current, in value lower than a desired current, by the LED driver to the plurality of series connected LEDs, resulting in a forward voltage across the plurality of series connected LEDs lower than the maximum allowed voltage output of the LED driver, e) waiting during a predetermined wait time period, f) stepping up of the first current to a second current provided by the LED driver to the plurality of series connected LEDs.

Abstract: A power converter powers an LED fixture from a power supply, and comprises a primary circuit a primary winding; and a switch in series connection with the primary winding to in a conductive state of the switch connect the primary winding to the power supply; a secondary circuit comprising a secondary winding that is magnetically coupled with the primary winding for providing power to the LED fixture in response to a switching of the switch; the power converter further comprising: the power converter further comprising: a sensing circuit configured to generate a signal representative of the output voltage of the secondary winding, an edge of the signal representing an edge of the output voltage of the secondary winding in response to the switching of the switch; and a detecting circuit configured to derive timing data from the edges of the signal, to estimate a load of the power converter from at least one output parameter of the power converter, and to determine a momentary value of a voltage of the

Abstract: An LED driver comprises a current source and a power supply configured to provide a power supply output voltage to the current source. The LED driver further comprises a controller configured to measure a voltage drop over the current source and to generate a feedback signal in response to the measured voltage drop. The power supply comprises a power supply regulator configured to regulate the power supply output voltage of the power supply between a minimum power supply output voltage and a maximum power supply output voltage, the power supply regulator comprising a power supply regulator input. The feedback signal is provided to the power supply regulator input, in a range from a first feedback signal value representing a minimum power supply output voltage to a second feedback signal value representing a maximum power supply output voltage.

Abstract: A power converter powers an LED fixture from a power supply, and comprises a primary circuit a primary winding; and a switch in series connection with the primary winding to in a conductive state of the switch connect the primary winding to the power supply; a secondary circuit comprising a secondary winding that is magnetically coupled with the primary winding for providing power to the LED fixture in response to a switching of the switch; the power converter further comprising: the power converter further comprising: a sensing circuit configured to generate a signal representative of the output voltage of the secondary winding, an edge of the signal representing an edge of the output voltage of the secondary winding in response to the switching of the switch; and a detecting circuit configured to derive timing data from the edges of the signal, to estimate a load of the power converter from at least one output parameter of the power converter, and to determine a momentary value of a voltage of the

Abstract: An LED driver comprises a current source and a power supply configured to provide a power supply output voltage to the current source. The LED driver further comprises a controller configured to measure a voltage drop over the current source and to generate a feedback signal in response to the measured voltage drop. The power supply comprises a power supply regulator configured to regulate the power supply output voltage of the power supply between a minimum power supply output voltage and a maximum power supply output voltage, the power supply regulator comprising a power supply regulator input. The feedback signal is provided to the power supply regulator input, in a range from a first feedback signal value representing a minimum power supply output voltage to a second feedback signal value representing a maximum power supply output voltage.