{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

4902_C2009_Studio_5_short

4902_C2009_Studio_5_short - Studio 5 Review Current Source...

Info icon This preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Studio 5 Review Current Source Active Load Bandwidth of Common Source Amplifier
Image of page 1

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

View Full Document Right Arrow Icon
2 Current source Ideal goal Small signal model: Open circuit “R D =
Image of page 2
3 Realizing current source: MOSFET Large signal nonideality: "Compliance range" Looks like current source only for V DS >V GS -V TH V DS = V GS - V TH SATURATION
Image of page 3

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

View Full Document Right Arrow Icon
4 MOSFET I D -V DS characteristic for fixed V GS Small-signal nonideality: slope in active region V DS = V GS - V TH
Image of page 4
5 Modify small-signal model: Finite r ds current source Slope = I/ V Ideal: zero slope r o = r o = " V " I SLOPE = " I " V = 1 r o V DS = V GS - V TH r o
Image of page 5

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

View Full Document Right Arrow Icon
6 Caution: R on vs. r o confusion! R on Triode region Large signal True resistance (V-I through origin) r o Saturation region Small signal Models nonideality of current source V DS = V GS - V TH SATURATION TRIODE SLOPE = 1/r o SLOPE = 1/R on
Image of page 6
7 I D - V DS Characteristic for Different V GS "Family" of curves INCREASING V GS
Image of page 7

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

View Full Document Right Arrow Icon
8 I D - V DS Characteristic for Different V GS Extrapolate backward: intersect at V DS -axis
Image of page 8
9 1/slope provides small signal resistance r o Intersect at -1/ λ Slope: Typical λ values: 0.01 V -1 L > 1μm 0.2 V -1 L < 1 μm 1 r o = I D 1 " # r o = 1 " I D
Image of page 9

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

View Full Document Right Arrow Icon
10 MOSFET small signal model r o in parallel: Model nonideality of current source due to channel length modulation r o = 1 " I D g m = 2 I D V GS " V TH r o
Image of page 10
Image of page 11
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