25_Lecutre - EE 114 Lecture 25 Lecture 25 OTA Feedback...

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
EE 114 Lecture 25 R. Dutton, B. Murmann 1 EE114 (HO #29) Lecture 25 OTA Feedback Circuits (Part III) R. Dutton, B. Murmann Stanford University R. Dutton, B. Murmann 2 Poor Man’s OTA Circuit With Cascodes Objective: increase low frequency loop gain precision EE114 (HO #29) V DD V xm V xp V o V BN I TAIL /2 I TAIL C s C f v o v i Magic battery biasing Magic battery biasing
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
EE 114 Lecture 25 R. Dutton, B. Murmann 3 AC Equivalent Model Cascodes help increase low frequency loop gain roughly by the intrinsic device gain ~100 in the EE114 technology EE114 (HO #29) v i v o C L C f C s G m =g m /2 C gdn C gs /2 2r on R op Z c R on C x x s f f C C C C + + = ! ( ) ( ) ( ) op on r int v op on o r int v on on m on on m on on r int v op op mp op op mp op op r r a R R R a r r g r r ' g r R a r r g r r g r R 2 2 2 2 1 1 ! = " ! " ! " + = " ! " ! + = o m R G T ! = 0 R. Dutton, B. Murmann 4 Impact of C gdn Z c ~ 1/g m ’ if R op < r on But this is not the case here Using the result from lecture 10 EE114 (HO #29) v i v o C L C f C s G m =g m /2 C gdn C gs /2 2r on R op Z c R on C x s frequencie high at 1 DC near 1 1 1 ' g Z r r ' g R Z r sC R ' g Z m c op on m op c on Ltot op m c ! ! ! " " " " # $ % % % % & + ! [ ] ( ) c on m gdn gs x Z r G ) s ( K ; C ) s ( K C C 2 1 2 ! " ! + =
Image of page 2
EE 114 Lecture 25 R. Dutton, B. Murmann 5 10 0 10 5 10 10 10 -1 10 0 10 1 10 2 f [Hz] | K ( f ) | K versus Frequency
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern