fairchild 公司的fsgm0565是集成了sensefet的pwm控制器,特别设计用于离线开关电源(smps),最大限度降低外接元件数量. pwm控制器包括固定频率振荡器,uvlo, 前沿消隐(leb),优化栅极驱动器,软起动,用于回路补偿的温度补偿精密电流源,以及自保护低矮路.内部的高压sensefet可达650v,主要用在lcd tv和监视器,stb和dvd的电源.本文介绍fsgm0565主要特性,方框图, pwm电路图,典型应用电路, 演示板电路图和所用材料清单(bom).

fairchild semiconductor’s power switch improves off-line power supply designs

the fsgm0565r is an integrated pulse width modulation (pwm) controller and sensefet specifically designed for offline switch-mode power supplies (smps) with minimal external components. the pwm controller includes an integrated fixed-frequency oscillator, under-voltage lockout (uvlo), leading-edge blanking (leb), optimized gate driver, internal soft-start, temperature-compensated precise current sources for loop compensation, and self-protection circuitry. compared with a discrete mosfet and pwm controller solution, the fsgm series can reduce total cost, component count, size, and weight; while simultaneously increasing efficiency, productivity, and system reliability. this device provides a basic platform suited for cost-effective design of a flyback converter.

fsgm0565主要特性:

soft burst-mode operation for low standby power consumption and low noise

precision fixed operating frequency: 66khz

pulse-by-pulse current limit

various protection functions: overload protection (olp), over-voltage protection (ovp), abnormal over-current protection (aocp), internal thermal shutdown (tsd) with hysteresis, output short protection (osp), and under-voltage lockout (uvlo) with hysteresis

auto-restart mode

internal startup circuit

internal high-voltage sensefet: 650v

built-in soft-start: 15ms

fsgm0565应用:

power supply for lcd tv and monitor, stb and dvd combination

图1.fsgm0565内部方框图

图2.fsgm0565 pwm电路图

图3.fsgm0565典型应用电路图

图4.反常过流保护

图5.fsgm0565演示板电路图

图6.fsgm0565演示板变压器电路

fsgm0565演示板材料清单(bom):