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这是12V升到220V的电路,仿真时发现在MOS管导通期间上面还有将近5V的电压,不是导通压降,观察变压器原边的一个绕组发现上面有负压,这个负压造成MOS管上的压降,请问这是怎么形成的???
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上图是MOS管两端电压,开始时正常,然后导通时有较大的压降,最后稳定在5V左右.MOSFET用的理想MOS(换成IRFP460波形基本一样)
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/46/1160872110.jpg?x-oss-process=image/watermark,g_center,image_YXJ0aWNsZS9wdWJsaWMvd2F0ZXJtYXJrLnBuZz94LW9zcy1wcm9jZXNzPWltYWdlL3Jlc2l6ZSxQXzQwCg,t_20');}" onmousewheel="return imgzoom(this);">