<p><b>C<sub>iss</sub>、C<sub>rss</sub>和C<sub>oss</sub>的电容特性是影响MOSFET开关特性的重要因素。</b></p>
<p><b><u>C<sub>iss</sub>:输入电容(C<sub>iss</sub>=C<sub>gd</sub>+C<sub>gs</sub>)</u></b></p>
<p> ⇒栅极-漏极和栅极-源极电容之和:它影响延迟时间;C<sub>iss</sub>越大,延迟时间越长。</p>
<p><b><u>C<sub>rss</sub>:反向转移电容(C<sub>rss</sub>=C<sub>gd</sub>)</u></b></p>
<p> ⇒栅极-漏极电容:C<sub>rss</sub>越大,漏极电流上升特性越差,这不利于MOSFET的损耗。高速驱动需要低电容。</p>
<p><b><u>C<sub>oss</sub>:输出电容(C<sub>oss</sub>=C<sub>gd</sub>+C<sub>ds</sub>)</u></b></p>
<p> ⇒栅极-漏极和漏极-源极电容之和:它影响关断特性和轻载时的损耗。如果<sub>Coss</sub>较大,关断dv/dt减小,这有利于噪声。但轻载时的损耗增加。</p>
<p><img alt="MOSFET的电容模型" data-entity-type="file" data-entity-uuid="3d326161-626e-4d5d-ba0a-e249ca9b39b3" src="/sites/default/files/inline-images/%E5%9B%BE3-11%EF%BC%88a%EF%BC%89MOSFET%E7%9A%84%E7%94%B5%E5%AE%B9%E6%A8%A1%E5%9E%8B.png" /></p>
<p>图3-11(a)MOSFET的电容模型</p>
<p><img alt="MOSFET的典型电容特性" data-entity-type="file" data-entity-uuid="c71754a1-0dc6-4ea9-8a62-9d2e85e4d91d" src="/sites/default/files/inline-images/%E5%9B%BE3-11%EF%BC%88b%EF%BC%89MOSFET%E7%9A%84%E5%85%B8%E5%9E%8B%E7%94%B5%E5%AE%B9%E7%89%B9%E6%80%A7.png" /></p>
<p>图3-11(b)MOSFET的典型电容特性</p>
<p>文章来源:<a href="https://toshiba-semicon-storage.com/cn/semiconductor/knowledge/e-learni…;