5l0380做的4V3A开关电源毛刺很大,如何改善

4v输出:
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6V输出:
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毛刺很大,频率是开关频率,原理图如下
为什么pdf格式文件上传成功了,但下不下来500) {this.resized=true; this.width=500; this.alt='这是一张缩略图，点击可放大。\n按住CTRL，滚动鼠标滚轮可自由缩放';this.style.cursor='hand'}" onclick="if(!this.resized) {return true;} else {window.open('http://u.dianyuan.com/bbs/u/76/2420581240199454.gif');}" onmousewheel="return imgzoom(this);">