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/45/1158562154.gif');}" onmousewheel="return imgzoom(this);">300W电源 问题求救
300W电源 5V/60A ,我用TL494做半桥,在40A 以上时就有吱吱叫声,加到15A以上时后,IC 8,11P,的波形有凹陷,负载越大,凹陷越大,等于多切了段波形,切点正是另一管的切换点,请各位给点意见,半桥是否都存在这现象,都遇到同样问题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/45/1158562154.gif');}" onmousewheel="return imgzoom(this);">
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/45/1158562154.gif');}" onmousewheel="return imgzoom(this);">