Method and apparatus for varying current limit to limit an output power of a power supply

用于改变电流极限以限制电源的输出功率的方法和设备

Abstract

公开了一种电源控制器。一种示例性电源控制器包括输入电压检测输入端,该输入电压检测输入端被耦合以检测代表电源的输入电压的输入电压检测信号。输出电压检测输入端被耦合以检测代表该电源的输出电压的输出电压检测信号。电流极限电路被耦合以产生电流极限信号。该电流极限信号与第一比率有关地改变,该第一比率代表该电源的输入电压与经缩放的输出电压之乘积与该电源的输入电压和经缩放的输出电压之和的比率。驱动信号发生器被耦合以响应于该电流极限信号来产生驱动信号,以驱动该电源的功率开关,以响应于输入电压来限制该电源的输出功率。
A power supply controller is disclosed. An example power supply controller includes an input voltage sense input coupled to sense an input voltage sense signal representative of an input voltage of a power supply. An output voltage sense input is coupled to sense an output voltage sense signal representative of an output voltage of the power supply. A current limit circuit is coupled to generate a current limit signal. The current limit signal is varied relative to a first ratio representative of a ratio of a product of the input voltage and a scaled output voltage of the power supply, to a sum of the input voltage and the scaled output voltage of the power supply. A drive signal generator is coupled to generate a drive signal in response to the current limit signal to drive the power switch of the power supply to limit an output power of the power supply in response to the input voltage.

Claims

Description

Topics

Download Full PDF Version (Non-Commercial Use)

Patent Citations (5)

    Publication numberPublication dateAssigneeTitle
    US-2008247202-A1October 09, 2008Power Integrations, Inc.Method and apparatus for sensing multiple voltage values from a single terminal of a power converter controller
    US-2009303756-A1December 10, 2009Pei-Lun Huang, Kuang-Ming ChangMaximum output power control of a flyback converter
    US-7486062-B2February 03, 2009Power Integrations, Inc.Method and apparatus for trimming current limit and frequency to maintain a constant maximum power
    US-7502235-B2March 10, 2009Richtek Technology Corp.Output power limit for a switching mode power converter by a current limit signal having a multi-slope waveform
    US-7616454-B2November 10, 2009System General CorporationControl circuit having programmable waveform for limiting output power of power converter

NO-Patent Citations (1)

    Title
    FAIRCHILD SEMICONDUCTOR: "Design Guidelines for Flyback Converters Using FSQ-series Fairchild Power Switch", 《FAIRCHILD SEMICONDUCTOR APPLICATION NOTE AN-4150》, 31 December 2006 (2006-12-31)

Cited By (6)

    Publication numberPublication dateAssigneeTitle
    CN-103546035-AJanuary 29, 2014力林科技股份有限公司Flyback-based power conversion apparatus and power conversion method thereof
    CN-103546035-BJanuary 13, 2016力林科技股份有限公司以反激式结构为基础的电源转换装置及其电源转换方法
    CN-103795278-AMay 14, 2014电力集成公司分离式电流镜线路感测
    CN-103916099-AJuly 09, 2014西安华芯半导体有限公司一种低成本片上振荡器
    CN-103916099-BAugust 17, 2016西安紫光国芯半导体有限公司一种低成本片上振荡器
    CN-104052295-ASeptember 17, 2014电力集成公司负载选择式输入电压感测器