公开(公告)号：US20040228152A1

公开(公告)日：2004-11-18

申请号：US10765385

申请日：2004-01-27

Applicant: Intersil Americas Inc., State of Incorporation: Delaware

Inventor： Eric Magne Solie

IPC: H02M001/00

CPC classification number: H02M1/36 ,  H02M2001/0025

Abstract: A soft start circuit for a DC-DC converter has an input reference voltage coupled to an error amplifier and to a soft start capacitor. A feedback resistor is coupled between an output node and the error amplifier, whose output is coupled to a pulse width modulator (PWM). The PWM output is coupled through an inductor to the output node, to which an output capacitor referenced to ground is coupled. Means is provided to charge up the soft start capacitor to the output voltage while the converter is disabled. As a result, when enabled, the converter will not discharge the output capacitor, but will ramp the output voltage to the voltage Vref without excessive currents.

Abstract translation: 用于DC-DC转换器的软启动电路具有耦合到误差放大器和软启动电容器的输入参考电压。 反馈电阻耦合在输出节点和误差放大器之间，其输出耦合到脉宽调制器（PWM）。 PWM输出通过电感器耦合到输出节点，与地面相关的输出电容耦合到输出节点。 提供了在转换器禁用时将软启动电容充电到输出电压的手段。 因此，当使能时，转换器不会对输出电容器放电，但会将输出电压斜坡上升到电压Vref，而不会有过大的电流。