脉冲频率100Hz- 1KHz,占空比10%,上升沿10uS.
在开关电源输出与负载间串入MOS管作为负载开关,用以上脉冲控制MOS管开关.
测误差放大器输出波形,可以看到误差放大器输出已是低频间歇振荡.
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上图中上面波形是负载开关控制信号,频率100Hz,5V/DIV.
上图中下面波形是误差放大器输出波形,有间歇.2V/DIV
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上图中上面波形是负载开关控制信号,频率100Hz,5V/DIV.
上图中下面波形是电源输出波形.2V/DIV.
在此工作条件下,电源环路已严重失去平衡.
请大家指教如何改善?
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