{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# lec11 - 6.012 Microelectronic Devices and Circuits Fall...

This preview shows pages 1–6. Sign up to view the full content.

6.012 - Microelectronic Devices and Circuits - Fall 2005 Lecture 11-1 Lecture 11 - MOSFET (III) MOSFET Equivalent Circuit Models October 18, 2005 Contents : 1. Low-frequency small-signal equivalent circuit model 2. High-frequency small-signal equivalent circuit model Reading assignment: Howe and Sodini, Ch. 4, § 4.5-4.6

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

View Full Document
6.012 - Microelectronic Devices and Circuits - Fall 2005 Lecture 11-2 Key questions What is the topology of a small-signal equivalent cir- cuit model of the MOSFET? What are the key dependencies of the leading model elements in saturation?
6.012 - Microelectronic Devices and Circuits - Fall 2005 Lecture 11-3 1. Low-frequency small-signal equivalent cir- cuit model Regimes of operation of MOSFET: V GS V BS V DS I D V DS I D V GS V GS =V T V DSsat =V GS -V T 0 0 linear saturation cutoff Cut-oﬀ : I D =0 Linear : I D = W L μ n C ox ( V GS - V DS 2 - V T ) V Saturation : I D = I Dsat = W 2 L μ n C ox ( V GS - V T ) 2 [1+ λ ( V - V DSsat )] Eﬀect of back bias: V T ( V BS )= V To + γ ( ± - 2 φ p - V - ± - 2 φ p )

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

View Full Document
6.012 - Microelectronic Devices and Circuits - Fall 2005 Lecture 11-4 Small-signal device modeling In many applications, interested in response of device to a small-signal applied on top of bias: V GS V BS V DS I D +i d v gs v bs v ds + - + + - - Key points: Small-signal is small response of non-linear components becomes linear Can separate response of MOSFET to bias and small signal. Since response is linear, superposition can be used eﬀects of diﬀerent small signals are independent from each other
6.012 - Microelectronic Devices and Circuits - Fall 2005 Lecture 11-5 V GS V BS V DS I D +i d v gs v bs v ds + - + + - - V GS V BS V DS I D i d v gs v bs

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.

{[ snackBarMessage ]}

### Page1 / 18

lec11 - 6.012 Microelectronic Devices and Circuits Fall...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online