In at least one embodiment, a controller allows triac-based dimmer to properly function and dim a load whose voltage is regulated by a switching power converter. In at least one embodiment, the switching power converter includes a switch to control voltage conversion of an input voltage to the switching power converter, wherein phase delays are introduced in the input voltage by a triac-based dimmer during a dimming period. In at least one embodiment, the controller is configured to control the switch of the switching power converter to establish an input resistance of the switching power converter during a dimming portion of the input voltage, wherein the input resistance allows the triac-based dimmer to phase modulate a supply voltage to the dimmer so that an output voltage of the dimmer has a substantially uninterrupted phase delay during each half-cycle of the supply voltage during the dimming period.