Patent ID: 8169154

Claim:
A variable load circuit for use with a lighting control device, and arranged to operate with two different load characteristics during a half cycle of an applied alternating signal, the variable load circuit comprising: means responsive to the applied alternating signal for: allowing current flow in response to voltage applied during one portion of the half cycle of the applied alternating signal; allowing the variable load circuit to act as a constant current sink during another portion of the half cycle; allowing the variable load circuit to operate independently of any external load that is connected to the variable load circuit; further comprising a secondary load circuit portion that is arranged to operate during part of the half cycle of the applied alternating signal; and wherein the secondary load circuit portion comprises a first switch arranged to switch the secondary load circuit in and out of the variable load circuit, and further wherein the first switch is a first transistor; wherein the variable load circuit further comprises: a trigger circuit portion to provide a current or voltage to a trigger terminal of the first transistor when a voltage above a threshold voltage is applied to the variable load circuit.