Method and Apparatus for Determining a Target Light Intensity From a Phase-Control Signal

An lamp configured to receive a phase-control voltage characterized by a duty cycle, the lamp comprising:

• a lighting load;
• a load regulation circuit configured to receive a drive control signal and to control the intensity level of the lighting load in response to the drive control signal;
• and
• a control circuit configured to receive a signal representative of the intensity level of the lighting load, and to generate the drive control signal to cause the load regulation circuit to adjust the intensity level of the lighting load towards a target level;
• wherein the control circuit is configured to determine the target level for the lighting load in response to the duty cycle of the phase-control voltage, the control circuit configured to adjust the target level for the lighting load using a first time constant in response to changes in the duty cycle of the phase-control voltage that are less than a threshold amount, and to adjust the target level for the lighting load using a second time constant in response to changes in the duty cycle of the phase-control voltage that are greater than the threshold amount, where the second time constant is less than the first time constant.