According to the disclosed embodiment of the invention, a circuit and method for stabilizing an operating characteristic of a compact fluorescent lamp driven by a ballast circuit having an operating frequency controlled by a component value, may comprise a first circuit connected to said ballast circuit for applying the component value thereto; and a second circuit connected to the ballast circuit for changing the component value so as to stabilize the operating characteristic. The operating characteristic may be power, current, voltage or crest factor for example. The second circuit changes the component value in response to a bus voltage of the ballast circuit and includes a switching device such as a transistor responsive to the bus voltage. In the disclosed embodiment the component value is a resistance, the first circuit comprises a first resistor, the second circuit comprises a second resistor, and the switching device selectively connects the second resistor to said ballast circuit in response to the bus voltage exceeding a predetermined threshold.

 
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