①共源极(CS,Common-Source)放大电路
②共漏极(CD,Common-Drain)放大电路
③共栅极(CG,Common-Gate)放大电路
(1) 共源放大电路
a.直流分析:
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b.交流分析:
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(2)共漏放大电路(也称源极跟随器)
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(3)共栅放大电路
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总结:
- 场效应管种类很多,主要有结型和绝缘栅场效应管。Ø 结型有N沟道和P沟道两种, 栅源必须加反偏压才能工作,如N沟道在uGS<0下工作, P沟道在uGS>0下工作。Ø 绝缘栅场效应管MOSFET有N沟道增强型、 N沟道耗尽型、 P沟道增强型、P沟道耗尽型四种类型。增强型不存在原始导电沟道,uGS只在单一极性或正或负工作;而耗尽型存在原始沟道,uGS可正可负。
- 场效应管是单极型电压控制器件,具有输入电阻高, 般可达109W。
- 场效应管放大电路主要有共源、共栅和共漏三种基本组态放大器。
- 静态偏置电路主要有自给偏置电路和分压式偏置电路两种。自给偏置电路适用于结型和耗尽型场效应管。而对增强型场效应管只能采用分压式偏置电路。
- 静态分析可采用解析法和图解法。
- 动态分析与三极管基本相似,主要采用微变等效电路法进行分析。