### Lecture 1: AFD01 - Course overview and introduction.(Active Filter Design)

##### Lecture Details :

video lectures from iit professors.... not available in NPTEL.....

video Lectures on "Active Filter Design" by Dr.Shanthi Pavan , IIT Madras

for more videos .... www.satishkashyap.com

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Lecture 1 - Course overview and introduction.

Lecture 2 - The Butterworth approximation

Lecture 3 - The Chebyshev approximation

Lecture 4 - The Chebyshev approximation (contd)

Lecture 5 - The Chebyshev approximation (contd), the Inverse Chebyshev approximation

Lecture 6 - The Inverse Chebyshev approximation (contd).

Lecture 7 - Synthesis of doubly terminated all-pole LC ladders filters

Lecture 8 - Synthesis of doubly terminated LC ladders (contd).

Lecture 9 - Synthesis of doubly terminated LC ladders with finite zeros of transmission.

Lecture 10 - Network sensitivity - low sensitivity of doubly terminated ladders

Lecture 11 - Introduction to frequency transformations.

Lecture 12 - Frequency (reactance) transformations (contd) - properties of the driving

impedance of lossless LC networks- Tellegen's theorem and positive real functions.

Lecture 13 - Driving point impedance of LC networks (contd), Low Pass-to-Low Pass, Low

Pass-to-Band Pass, Low Pass-to-High Pass and Low Pass-to-Band Stop transformations

Lecture 14 - The Richard's Transformation, RC-CR transformation

Lecture 15 - Emulation of an inductor with a capacitor and controlled sources, the

gyrator, a second order transconductor capacitor filter.

Lecture 16 - Cascade of biquads realization of high order low pass filters, equivalence

of the parallel RLC and series RLC circuits with their Gm-C counterparts.

Lecture 17 - The idea of Dynamic Range in active filters - impedance scaling and its

effect on dynamic range

Lecture 18 - Introduction to noise in electrical networks.

Lecture 19 - Introduction to noise in electrical networks (contd), the idea of node

scaling.

Lecture 20 - Dynamic range scaling in active filters.

Lecture 21 - Biquad Ordering.

Lecture 22 - Active Ladder Emulation / Leapfrog Filters, Effect of Transconductor

nonidelaities (parasitic capacitance/output resistance).

Lecture 23 - Effect of Transconductor Nonidealities (contd) - parasitic poles.

Lecture 24 - Viewing the Gm-C biquad as a Double Integrator Loop, Revisiting the Effect

of Finite Gain of the Transconductors.

Lecture 25 - Single-ended Versus Differential Filters, Introducing the Differential-pair

Based Fully Differential Transconductor, the Need for Common-mode Feedback

Lecture 26 - Common-mode Feedback (continued).

Lecture 27 - Common-mode Feedback (continued), examples of Common-mode Detectors.

Lecture 28 - Stability of the Common-mode Feedback Loop

Lecture 29 - Common-mode Positive Feedback in Gyrators.

Lecture 30 - Common-mode Positive Feedback in Gyrators (contd), Noise in the

Differential Pair.

Lecture 31 - Noise in the Differential Pair (contd), Linearity of the Differential Pair,

Cascoding to Improve Output Impedance

Lecture 32 - Noise in Cascodes, Layout Considerations and Multi-finger Transistors.

Lecture 33 - Linearizing the Differential Pair, Resistive Degeneration.

Lecture 34 - Noise in Degenerated Transconductors, The Folded Cascode and Noise Analysis

Lecture 35 - Stabilizing filter bandwidth over process and temperature - the resistor

servo loop, master-slave loops.

Lecture 36 - Turning the filter into a VCO to estimate center frequency, example of a

practical precision fixed-gm bias circuit.

Lecture 37 - Introduction to accurate measurement and characterization techniques for

active filters.

Lecture 38 - Introduction to Active-RC filters.

Lecture 39 - Active-RC filters (contd), the use of an OTA instead of an opamp, swing and

noise considerations, single stage OTAs

Lecture 40 - Multistage OTAs for use in CMOS Active-RC filters.

Lecture 41 - The Miller compensated opamp in active-RC filters, noise considerations,

noise in active-RC filters .

Lecture 42 - Distortion and Intermodulation in filters, miscellaneous discussion on fixed gm-bias circuits

##### Course Description :

Contents:

Course overview and introduction,The Butterworth approximation,The Chebyshev approximation,The Chebyshev approximation (contd),The Chebyshev approximation (contd), the Inverse Chebyshev approximation,The Inverse Chebyshev approximation (contd),Synthesis of doubly terminated all-pole LC ladders filters,Synthesis of doubly terminated LC ladders (contd),Synthesis of doubly terminated LC ladders with finite zeros of transmission.

Network sensitivity - low sensitivity of doubly terminated ladders,Introduction to frequency transformations,Frequency (reactance) transformations (contd) - properties of the driving impedance of lossless LC networks- Tellegen's theorem and positive real functions,Driving point impedance of LC networks (contd), Low Pass-to-Low Pass, Low Pass-to-Band Pass, Low Pass-to-High Pass and Low Pass-to-Band Stop transformations,The Richard's Transformation, RC-CR transformation,Emulation of an inductor with a capacitor and controlled sources, the gyrator, a second order transconductor capacitor filter.

Cascade of biquads realization of high order low pass filters, equivalence of the parallel RLC and series RLC circuits with their Gm-C counterparts,The idea of Dynamic Range in active filters - impedance scaling and its effect on dynamic range,Introduction to noise in electrical networks,Introduction to noise in electrical networks (contd), the idea of node scaling,Dynamic range scaling in active filters. Lecture 21 - Biquad Ordering,Active Ladder Emulation / Leapfrog Filters, Effect of Transconductor nonidelaities (parasitic capacitance/output resistance),Effect of Transconductor Nonidealities (contd) - parasitic poles,Viewing the Gm-C biquad as a Double Integrator Loop, Revisiting the Effect of Finite Gain of the Transconductors,

Single-ended Versus Differential Filters, Introducing the Differential-pair Based Fully Differential Transconductor, the Need for Common-mode Feedback,Common-mode Feedback (continued) Common-mode Feedback (continued), examples of Common-mode Detectors,Stability of the Common-mode Feedback Loop,Common-mode Positive Feedback in Gyrators,Common-mode Positive Feedback in Gyrators (contd), Noise in the Differential Pair,Noise in the Differential Pair (contd), Linearity of the Differential Pair, Cascoding to Improve Output Impedance,Noise in Cascodes, Layout Considerations and Multi-finger Transistors. Lecture 33 - Linearizing the Differential Pair, Resistive Degeneration,

Noise in Degenerated Transconductors, The Folded Cascode and Noise Analysis Lecture 35 - Stabilizing filter bandwidth over process and temperature - the resistor servo loop, master-slave loops,Turning the filter into a VCO to estimate center frequency, example of a practical precision fixed-gm bias circuit,Introduction to accurate measurement and characterization techniques for active filters,Introduction to Active-RC filters,Active-RC filters (contd), the use of an OTA instead of an opamp, swing and noise considerations, single stage OTAs,Multistage OTAs for use in CMOS Active-RC filters,The Miller compensated opamp in active-RC filters, noise considerations,noise in active-RC filters,Distortion and Intermodulation in filters, miscellaneous discussion on fixed gm-bias circuits

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