A DC-DC converter includes a voltage conversion circuit unit, a control unit, and a capacitor check unit. The voltage conversion circuit unit converts an input voltage to a first voltage. The control unit controls the voltage conversion circuit unit based on a feedback voltage and a reference voltage. The capacitor check unit determines whether a capacitor is coupled to a capacitor coupling terminal based on sensing a voltage of the capacitor coupling terminal, which is selectively coupled to the first control unit.

A filament for a light bulb includes a tube and a filament material within the tube, wherein the filament material is configured to be in a liquid state while the light bulb is in use.

Various embodiments may relate to a dimming drive circuit for an illumination apparatus and an illumination apparatus including the dimming drive circuit, wherein the dimming drive circuit includes a filter circuit unit and a bleeder circuit unit, a main control module connected to the filter circuit unit and the bleeder circuit unit, respectively, and an auxiliary control module configured to reduce the current of the bleeder circuit unit and/or to switch off the bleeder circuit unit according to a characteristic input current of the dimming drive circuit prior to switch-off of the bleeder circuit unit by the main control module in a first operation state of the dimming drive circuit, and to prevent the filter circuit unit from releasing electrical energy via the bleeder circuit unit in a second operation state of the dimming drive circuit.