常见电路结构分析一：用二极管构成保护电路

一时失言乱红尘 2023-02-13 05:54 26阅读 0赞

### 一、开关二极管的典型应用：限制输入电压 ###

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电路分析：1、如果输入电压大于VCC，那上面的二极管导通，把A/D输入电压钳位在VDD加一个导通电压（一般0.2~~0.75伏左右），低于GND时，下面的二极管导通，把电位钳位在负的0.2~~0.75V之间，从而保护A/D输入不至于因输入电压太高而损坏。

2、两个二极管都是电压钳位，上端二极管把电池取样电压高端钳位到VDD+0.7V（即当电池取样电压低于VDD时二极管截止，高于VDD时，限定为VDD+0.7V），下端二极管把版电池取样低端电压权钳位到0-0.7V，以保护AD IN、端口。简单地说，上端二极防止取样电压过高，下端二极管防止取样电压出现负脉冲。一是保护IC，二是防止干扰。

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### 二、二极管保护电路的应用 ###

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###  三、用二极管电路极性保护 ###

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[https://www.cnblogs.com/sunshine-jackie/p/8794835.html][https_www.cnblogs.com_sunshine-jackie_p_8794835.html]

### 四、tvs二级管的电路应用 ###

分为单向和双向

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![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2d1dGllX2JhcnRob2xvbWV3_size_16_color_FFFFFF_t_70 4][]

[http://www.dzsc.com/showroom/tvs/news-1894.html][http_www.dzsc.com_showroom_tvs_news-1894.html]

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[https_www.cnblogs.com_sunshine-jackie_p_8794835.html]: https://www.cnblogs.com/sunshine-jackie/p/8794835.html
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