Switching power supply control circuit in quasi-resonant mode and control method

A switching power supply and control circuit technology, applied in control/regulation systems, high-efficiency power electronic conversion, electrical components, etc., can solve problems such as audio noise and valley jumping, achieve high system efficiency, good stability, and solve noise problems Effect

Active Publication Date: 2015-11-18
SILERGY SEMICON TECH (HANGZHOU) CO LTD
View PDF5 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, there is an obvious problem in the quasi-resonant mode, which is that the phenomenon of jumping valleys is prone to occur under a specific load, that is, the power switch tubes are turned on in two adjacent valleys in turn. When inside, there will be noticeable audio noise

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Switching power supply control circuit in quasi-resonant mode and control method
  • Switching power supply control circuit in quasi-resonant mode and control method
  • Switching power supply control circuit in quasi-resonant mode and control method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0031] Several preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the present invention is not limited to these embodiments. The present invention covers any alternatives, modifications, equivalent methods and schemes made on the spirit and scope of the present invention. In order to provide the public with a thorough understanding of the present invention, specific details are set forth in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details.

[0032] refer to figure 1 Shown is the schematic diagram of the switching power supply control circuit according to the quasi-resonant mode of the present invention. The switching power supply is an example of a flyback switching power supply. The flyback switching power supply includes a rectifier bridge, a primary winding Np and a second...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a switching power supply control circuit in a quasi-resonant mode and a control method. An output current sampling circuit is used for obtaining an output current feedback signal for representing output current information; the current sampled output current feedback signal is compared with a plurality of valley switching threshold values; when the output current feedback signal reaches a threshold voltage of a certain valley, a control circuit switches a current locked valley to another proper valley. Meanwhile, with arrangement of a retardation zone a phenomenon that valley jumping occurs when the output current feedback signal of the output current approaches the valley switching threshold value can be prevented. According to the invention, stability of locking of a valley in a quasi-resonant mode is high; and the influence by the input direct-current voltage fluctuation can be eliminated.

Description

technical field [0001] The invention relates to the field of switching power supplies, more specifically, to a quasi-resonant mode switching power supply control circuit and control method. Background technique [0002] The flyback switching power supply is widely used in the field of low-power DC / DC power conversion. When the flyback switching power supply works in the quasi-resonant mode, since the power switch tube is turned on when the drain voltage reaches the bottom position, it has a high Conversion efficiency and lower EMI interference, so this control mode has been widely used. However, there is an obvious problem in the quasi-resonant mode, which is that the valley-hopping phenomenon is prone to occur under a specific load, that is, the power switch tube is turned on in two adjacent valleys. When inside, there will be noticeable audio noise. Contents of the invention [0003] In view of this, the present invention proposes a quasi-resonant mode switching power ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H02M3/335H02M7/217
CPCH02M3/33507H02M1/0058Y02B70/10
Inventor 杨笑宇白永江
Owner SILERGY SEMICON TECH (HANGZHOU) CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap