Patent ID: 9265103
Filing Date: 2016-02-16
CPC Classification: H05B,Y02B

Claim Text:
1. An LED driver circuit for controlling direct current supplied to a plurality of serially connected segments of Light Emitting Diodes (LEDs) from a source of rectified alternating current voltage, said circuit comprising: a self-commutating circuit comprising a plurality of current control elements, each current control element having two ends, a first end connected to a junction between adjacent segments of LEDs along the plurality of serially connected LEDs and a second end connected to a shared path to ground, each current control element being coupled to an adjacent current control element by a cross-regulation circuit and controlled by a signal from an adjacent current control element; wherein each current control element includes a resistor connected in series with a constant current limiter, wherein each constant current limiter includes a transistor and the transistor includes a terminal connected to a switch between an amplifier and a comparator for controlling the current flowing through the current limiter; wherein a first cross-regulation circuit modulates current in a current control element in response to a signal from a second cross-regulation circuit; wherein the second cross-regulation circuit produces a signal in response to current flowing thru an adjacent current control element.