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|  |  | | | | | 等下，我试试啊，我还用给你贴我的UC3842的6脚输出波形嘛
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| | | | | | | | | | | | | | | 什么意思，刚刚上电保险丝爆了，现在害怕了，还得修电路，愁死了，不想弄了
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| | | | | | | | | | | | | | | | | | | 那你的意思应该多大，或者不要是嘛，给个建议呗。刚刚上电保险丝真爆了，以前最多只是烧保险丝，刚刚直接爆了，崩飞了，现在想想就后怕
本帖最后由 新手01号 于 2015-11-17 16:22 编辑
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| | | | | | | | | | | | | | | | | | | | | | | 那你的意思是我把C9拿掉就行了吧，会不会影响电路。还有为什么15nF电容易爆
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| | | | | | | | | | | | | | | | | | | | | | | | | 驱动很少接电容对地吧？感觉是怕米勒电容和此电容对地充放电时，高压击穿MOS的栅极~瞎猜的~  |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | 驱动那里根本不需要加电容的。不然的话会影响开关速度的。损耗很大。先去掉再看看。电流采样电阻既然改了就炸机，还是改回去再找原因。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 谢谢，今天有点害怕了，明天继续。弄好了的话，给你充话费吧，谢谢啦 本帖最后由 新手01号 于 2015-11-17 19:49 编辑
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 给楼主提供两个小细节，再玻璃管保险外面最好套上一段黄腊管或者热缩套管防止其爆裂产生的碎玻璃；在试机时最好串入一只60瓦左右的白炽灯泡。你的这个故障原因我感觉在TL431以及其附属电路当中，你再仔细查看一下
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| | | | | | | | | | | | | |  | | | | | | | | | | | | | | | | | | | 保险丝的建议太感谢了，为了安全，我再去买个空气开关。那个灯泡我接哪啊，我怕把灯泡也弄爆了。。。。，你再我看看电路图，我已经把全部的贴上去了，谢谢啦
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 要是短路或者烧坏器件造成的短路，灯泡会炸嘛  ，现在我用1A的保险丝有问题吗，不行想办法就换个2A的 本帖最后由 新手01号 于 2015-11-18 11:06 编辑
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 220V的市电直接加灯泡上面都没有问题，怎么会炸呢？你就用那种常用的白炽灯就行了。
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| | | | | | | | | | | | | | | | | | |  | | | | | | | | | | | | | | | | | | | | | | 后面短路都不会炸？那我就放心了，我还得买啊，现在手头没有啊
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 楼主你的问题太可爱了，下面的版主已经将白炽灯的用法告诉你了
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你改动哪里了？？？做一个红框，或者文字说明比较好~
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 图中画圈了。为什么UC3842的8脚接的灯会闪，我测过电压，8脚电压在1.3或者2.1v跳变，就不是5v
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 下午给你回复，我下午找个75k的功率电阻行吧
本帖最后由 新手01号 于 2015-11-20 10:49 编辑
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 看你输入电压的高低了，可以试试两个75K的并联使用。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 接灯闪，你最好吧实测的输出电压、电流波形也贴出来~
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 对啊，用电压表测的电压，但是上电想看UC3842的8脚波形时，是用示波器看的，然后保险丝就炸了，不知道是不是我用1A保险丝的原因。电流超量程才炸的
本帖最后由 新手01号 于 2015-11-23 14:16 编辑
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 别闹~如果10W+的输入功率的抗不了，那这保险也太烂啦~
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 示波器的地线主要要拔掉，或者你用隔离探头去测试波形。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
你的意思是我用探头测试呗，然后黑色的夹子不用呗，谢谢
本帖最后由 新手01号 于 2015-11-23 15:07 编辑
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 是示波器的交流输入线的地线拔掉，也就是指两PIN输入，当然你示波器有隔离变压器也是可以的。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 楼主你说的太职业了，我听不懂啊。。。。我发的示波器图片了，这台比较老，好使的话，我再用新的，你看看我刚刚上面说的对嘛
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你示波器后面不是有一根接市电的线吗？线有三个脚，把接地的那个脚剪掉就可以了。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 为什么要这样啊，不这样为什么不行啊，我这可是公司仪器啊，我怕老板说我，有没有输出是2脚输出是3脚的电源线啊
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 一个电源线而已，这也能挨说？？？去掉是因为这样的示波器探头的夹子是和电源线的地线相通的，当你测试MOS的DS间电压或者别的无隔离的波形，就相当和地短接...后果...夹子炸黑是小事，就怕示波器也坏了...
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 明白了，你的意思是，我用探头测UC3842的8脚电压时，夹子夹在数字GND上。这样一上电，就相当我的探头和夹子短路了，所以保险丝管才会爆炸的，对吧，我先出去下，一会回来马上回复你
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 谢谢大哥教导，等下晚上回来我就做实验，告诉你结果，顺便我私密你了
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 小部长，让我把报告给他，今天整理了一天报告，他问我了一个问题:我这个是自激式还是反激式开关电源电路呢？我现在有点拿不准了。应该是自激式吧
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你确定你这样可以测出来实际波形？？？你应该能测试出一个不大的交流波...  让你把示波器的电源线换成两项的插头，或者3项插头把地线剪断
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你的意思是让我用2插头的公头插在220V插座上呗，电源线另一侧插在示波器上吧
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你觉得那根地线有何保护作用？？？外壳部分几乎都是塑料的~！！
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 等晚上，我做下实验，现在做不了，做完告诉你结果哈，顺便我私密你了，你看看
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我的意思是，我换电阻，换线，看看能不能出波形啊。。。。。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 小部长，让我把报告给他，今天整理了一天报告，他问我了一个问题:我这个是自激式还是反激式开关电源电路呢？我现在有点拿不准了。应该是自激式吧 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我想灯闪可不可能是3脚电流过大，我是不是得测3脚附近R12的上端电压是否大于1v吧。我小组小部长，把我的板子拿去研究了，坑爹啊，今天一天又没能测试，我就擦了
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 一般情况下的自激都是反激式的，这两种说法不是对立的分类，反激是一种拓扑的方式，对应的还有正激，半桥、全桥，自激是一种利用RC振荡产生开关信号的方式 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 那这种自激式的反激拓扑，大体应用在什么场合？？为什么会从反激拓扑中分出一块？有何优缺点？？期待版主讲解一下~  |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 自己找找RCC的资料看看就明白了。论坛里面有很多关于这方面的的介绍的。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 现在小头头让我研究指示灯跳转电路，你看看我说的对嘛。 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你看看，我研究的指示灯跳转电压对嘛，小头头真烦人，拿着我的板子不给我，让我研究理论，哎
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 原理图看不太清楚，大概的原理，就是几个比较器在哪里切换。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我做了个word，这回能看清了，主要是我这个跟别人的不一样，别人的我都能看明白，到我这就不行了
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 主要是你这个运放都集成在一起了，看的比较费劲，自己拆开看看，就很明白了。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 今天突然有一想法。我单独接24直流电压源的时候（把mos管拆了，别的一点没动），LED2指示灯正常，8脚输出5V。那灯闪主要问题就是7脚供电问题吧。现在灯闪，说明UC3842启动没问题，芯片已经启动了。只是反馈线圈输出正常供电有问题。是不是伴随MOS管开断，在初级线圈电流也是开断的，形成交流。然后在反馈线圈感应出13v的电压对吧。如果对的话，岂不是反馈线圈9脚输出高频13V交流电压吧，那我D5用的1N4007，岂不是很傻。由于反应不够迅速，才会使7脚电压不稳定，导致LED2灯闪对吧。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 这个是可以的。不过注意耐压不要超了
本帖最后由 hlp330 于 2015-12-9 11:31 编辑
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你想的有点多哦~。器件的反应速度应该是nS级别的，你3842的驱动MOS应该也是50KHZ以上的~然而人眼是有占留的~50HZ以上的频率，人眼已经识别不到闪烁了~ |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 你的意思是，我的灯闪，并不是因为我用的是1N4007，没用快速整流管而导致的呗
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 额~才注意看到你用的是1N4007，这不是快管~你换一个快管试试~！！
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 我可不可以用IN4148暂时代替下D5快速恢复二极管呢 |
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 今天突然有一想法。我单独接24直流电压源的时候（把mos管拆了，别的一点没动），LED2指示灯正常，8脚输出5V。那灯闪主要问题就是7脚供电问题吧。现在灯闪，说明UC3842启动没问题，芯片已经启动了。只是反馈线圈输出正常供电有问题。是不是伴随MOS管开断，在初级线圈电流也是开断的，形成交流。然后在反馈线圈感应出13v的电压对吧。如果对的话，岂不是反馈线圈9脚输出高频13V交流电压吧，那我D5用的1N4007，岂不是很傻。由于反应不够迅速，才会使7脚电压不稳定，导致LED2灯闪对吧。
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 输出端没有电压，UC3842的8脚电压在1.3和2.1v左右跳变
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| | | | | 这个故障楼主解决了没有？请将最后处理的经验分享一下，我们共同提高一下嘛，谢谢了
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| | | | | | | 没有呢，手头没有快速恢复二极管，这两天才到货，不知道能不能用IN4148 暂时代替下D5呢，我怕烧管
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| | | | | | | | | 不行的，4148只是开关管而已，其特性参数和快反二极管有很大的差异
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