MIT6_012s09_lec09

MIT6_012s09_lec09 - MIT OpenCourseWare http/ocw.mit.edu...

This preview shows pages 1–5. Sign up to view the full content.

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

View Full Document

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: MIT OpenCourseWare http://ocw.mit.edu 6.012 Microelectronic Devices and Circuits Spring 2009 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms . Lecture 9 MOSFET(II) MOSFET I-V CHARACTERISTICS(contd.) Outline 1. The saturation region 2. Backgate characteristics Reading Assignment: Howe and Sodini, Chapter 4, Section 4.4 6.012 Spring 2009 Lecture 9 1 1. The Saturation Region Geometry of problem Regions of operation: • Cut-off: V GS < V T – No inversion layer anywhere underneath the gate I = D • Linear: V GS >V T and 0 < V DS < V GS -V T : – Inversion layer everywhere under the gate W V DS = I D L • μ n C ox V GS − 2 − V T • V DS 6.012 Spring 2009 Lecture 9 2 The Saturation Region (contd.) • Saturation: V GS > V T , and V DS > V GS - V T : – Inversion layer “pinched-off” at drain end of channel I D = W • μ n C ox [ V GS − V T ] 2 2 L Output characteristics: • Last lecture : To derive the above equations for I D , we used for Q N (y), the charge-control relation at location y: Q ( y ) = − C [ V − V ( y ) − V ] N ox GS T for V GS – V(y) ≥ V T . . Note that we assumed that (a) V BS = ⇒ V GS = V GB , and (b) V T is independent of y. See discussion on body effect in Section 4.4 of text....
View Full Document

{[ snackBarMessage ]}

Page1 / 16

MIT6_012s09_lec09 - MIT OpenCourseWare http/ocw.mit.edu...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online