Patent ID: 11870362
Assignee: WUXI CHIPOWN MICROELECTRONICS CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 19:
20. The switching power supply system according to claim 19, wherein the light-load detection circuit comprises a pre-pulse signal generation circuit, a pulse signal generation circuit and a light-load signal generation circuit,
wherein the pre-pulse signal generation circuit has an input terminal coupled to the second terminal of the sampling circuit, and is configured to generate and output a pre-pulse signal based on that a duration of a high level of the sampling voltage reaches a first preset duration;
the pulse signal generation circuit has an input terminal coupled to the input terminal of the pre-pulse signal generation circuit, and is configured to convert the pre-pulse signal into a pulse signal; and
the light-load signal generation circuit has an input terminal coupled to an output terminal of the pre-pulse signal generation circuit, and is configured to generate and output the light-load signal based on that the number of times of receiving the pulse signal reaches a second preset value.