1. A bleeder circuit, comprising:a) a bleeder module, having alternating current (AC) input through a triode alternating current (TRIAC) dimmer and a rectifying bridge to get input voltage to provide a load with power supply through a driving circuit, two ends of the bleeder module being connected to high and low potential terminals of an input voltage detecting circuit respectively; and
b) a bleeder control circuit, connected to a control terminal of the bleeder module; directly or indirectly detecting cross-zero point of input voltage; after the cross-zero point of input voltage is delayed by a second time, the bleeder module works to generate bleeder current, and a time between turn-on time of the TRIAC dimmer and a time that a driving circuit input current achieves a predetermined value is a first time;
wherein, when the first time is greater than a reference time, the second time is prolonged; and when the first time is smaller than the reference time, the second time is reduced, such that the first time is close to the reference time;
wherein the bleeder control circuit comprises an input voltage detecting circuit, an input current detecting circuit of a driving circuit, and a logic circuit; the logic circuit is connected to a control terminal of the bleeder module, and the input voltage detection circuit samples the input voltage; when the input voltage sample signal achieves a threshold voltage, after being delayed for a second time, the bleeder module is controlled by the logic circuit to generate bleeder current; the input current detecting circuit of the driving circuit detects the input current of the driving circuit, and when the sample current achieves a threshold current indicating a predetermined current, the bleeder current is controlled by the logic circuit to be zero; comparing the first time with the reference time, and adjusting the second time correspondingly according to the comparison result.