A driving device provides output power to an illumination device including a plurality of filaments is provided. A first converting module converts input power into direct current (DC) power. The first converting module includes a pair of first input terminals receiving the input power and a pair of first output terminals coupled to a first node and a second node and outputting the DC power. A first capacitor is coupled between the first node and a third node. A second capacitor is coupled between the second and third nodes. The first clamping module is connected to a first specific capacitor in parallel. The first specific capacitor is the first capacitor or the second capacitor. A second converting module converts the DC power to generate the output power.