There is provided a driving circuit for controlling power of a light source. The driving circuit includes a power converter and a dimming controller. The power converter is coupled between a power source and the light source, and can receive power from the power source and provide a regulated power to the light source. The dimming controller is coupled to the power converter, and can receive a switch monitoring signal. The switch monitoring signal can indicate an operation of a power switch coupled between the power source and the driving circuit. The dimming controller is further operable for adjusting the regulated power from the power converter by controlling a switch coupled in series with the light source according to the switch monitoring signal.