# Differences

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 university:courses:alm1k:alm-lab-11m [07 Feb 2022 15:02]Doug Mercer [Activity 11M: The Source follower (NMOS)] university:courses:alm1k:alm-lab-11m [07 Feb 2022 15:45]Doug Mercer [Procedure:] Both sides previous revision Previous revision 07 Feb 2022 15:45 Doug Mercer [Procedure:] 07 Feb 2022 15:02 Doug Mercer [Activity 11M: The Source follower (NMOS)] 20 May 2015 14:26 Doug Mercer [Hardware Setup:] 17 May 2015 19:27 Doug Mercer created 07 Feb 2022 15:45 Doug Mercer [Procedure:] 07 Feb 2022 15:02 Doug Mercer [Activity 11M: The Source follower (NMOS)] 20 May 2015 14:26 Doug Mercer [Hardware Setup:] 17 May 2015 19:27 Doug Mercer created Line 39: Line 39: {{ :​university:​courses:​alm1k:​alm_lab11m_e1.png?​150 |}} {{ :​university:​courses:​alm1k:​alm_lab11m_e1.png?​150 |}} - From the equation we can see that in order to obtain a gain close to one we can either increase R<​sub>​L​ or decrease r<​sub>​s​. We also know that r<​sub>​s​ is a function of I<​sub>​D​ and that as I<​sub>​D​ increases r<​sub>​s​ decreases. Also from the circuit we can see that I<​sub>​D​ is related to R<​sub>​L​ and that as R<​sub>​L​ increases I<​sub>​D​ decreases. These two effects work counter to each other in the simple resistive loaded ​emitter ​follower. Thus to optimize the gain of the follower we need to explore ways to either decrease r<​sub>​s​ or increase R<​sub>​L​ without effecting the other. It is important to remember that in MOS transistors I<​sub>​D​ = I<​sub>​S​ ( I<​sub>​G​ = 0 ). + From the equation we can see that in order to obtain a gain close to one we can either increase R<​sub>​L​ or decrease r<​sub>​s​. We also know that r<​sub>​s​ is a function of I<​sub>​D​ and that as I<​sub>​D​ increases r<​sub>​s​ decreases. Also from the circuit we can see that I<​sub>​D​ is related to R<​sub>​L​ and that as R<​sub>​L​ increases I<​sub>​D​ decreases. These two effects work counter to each other in the simple resistive loaded ​source ​follower. Thus to optimize the gain of the follower we need to explore ways to either decrease r<​sub>​s​ or increase R<​sub>​L​ without effecting the other. It is important to remember that in MOS transistors I<​sub>​D​ = I<​sub>​S​ ( I<​sub>​G​ = 0 ). {{ :​university:​courses:​alm1k:​alm_lab11m_e2.png?​400 |}} {{ :​university:​courses:​alm1k:​alm_lab11m_e2.png?​400 |}}