| 摘要 |
An apparatus, method and system are provided for controlling the solid state lighting, such as LEDs. An exemplary apparatus comprises: a switch for switching electrical current through the LEDs, a current sensor; a first comparator adapted to determine when a switch electrical current has reached a first predetermined threshold; a second comparator adapted to determine when the switch electrical current has reached a predetermined average current level; and a controller. The controller is adapted to turn the switch into an on state and an off state, to determine a first on time period as a duration between either a detection of a second predetermined current threshold or the turning the switch into the on state, and the detection of the predetermined average current level; to determine a second on time period as a duration between the detection of the predetermined average current level and the detection of the first predetermined current threshold; and to determine an on time period of the switch as substantially proportional to a sum of the first on time period and the second on time period. Additional exemplary embodiments utilize a difference between the first and second on time periods to generate an error signal to adjust the on time period of the switch.
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