Patent ID: 8896283

Claim:
A synchronous switching power converter with zero current detection, comprising: an inductor; a down bridge transistor coupled to the inductor and a ground as a synchronous rectifier as the synchronous switching power converter; and a zero current detecting circuit comprising: a zero current comparator coupled between the inductor and the down bridge transistor for receiving a fixed comparing level at a negative input end for comparison to change state of a comparing result; a delay unit, for delaying the comparing result to change state of a turn off signal according to a compensation voltage, to turn off the down bridge transistor when determining current on the inductor is zero; a transient state adjusting circuit coupled to the zero current comparator for indicating a transient period when detecting state of the turn off signal is changed; and an integrator coupled to the zero current comparator and the transient state adjusting circuit for integrating the compensation voltage by analog manner to adjust value of the compensation voltage and providing to the delay unit within the transient period; wherein the zero current comparator determines the integrator to integrate positively or negatively within the transient period.