折叠式共源共栅结构/折叠式共源共栅放大器-KIA MOS管

折叠式共源共栅结构

共(gong)(gong)源共(gong)(gong)栅级由(you)共(gong)(gong)源级实现电(dian)压到(dao)(dao)电(dian)流的转换，然后电(dian)流信(xin)号加到(dao)(dao)共(gong)(gong)栅级的源端。因此，构(gou)成共(gong)(gong)源共(gong)(gong)栅级时共(gong)(gong)源管(guan)和共(gong)(gong)栅管(guan)类型可以不同。

如图(tu)3.0.2.1，M1是输入器件：PMOS；M2是共(gong)源共(gong)栅(zha)器件：NMOS；I1为(wei)直流偏置电流源。

折叠式共源共栅放大器

折叠式(shi)共(gong)(gong)源共(gong)(gong)栅结(jie)构具(ju)有输出阻抗(kang)高、增(zeng)益高等(deng)优点，但同时折叠式(shi)共(gong)(gong)源共(gong)(gong)栅级(ji)直流功耗大(da)。

共源共栅放大器频率特性分析

节(jie)点(dian)近似法分(fen)析三个节(jie)点(dian)：A、X、Y，如(ru)图3.1.1.1所示。

折叠式共源共栅放大器

在这三个(ge)极点(dian)(dian)(dian)中，其中Win一般不(bu)考虑，在设计(ji)电路时，Wx选(xuan)择在高频处。因此：Wy是主极点(dian)(dian)(dian)，传(chuan)输函(han)数(shu)是单极点(dian)(dian)(dian)函(han)数(shu)。

折叠式共源共栅放大器

目前(qian)共(gong)(gong)(gong)源共(gong)(gong)(gong)栅(zha)放大器已(yi)经逐渐取代了传统(tong)的套筒(tong)式运放，因(yin)为(wei)共(gong)(gong)(gong)源共(gong)(gong)(gong)栅(zha)放大器的输出(chu)摆幅明显比它更大，而且易于(yu)对输入与输出(chu)进(jin)行操作(zuo)如图3.1.2.4所示，为(wei)一个PMOS的共(gong)(gong)(gong)源共(gong)(gong)(gong)栅(zha)放大器。

折叠式共源共栅放大器