06-F10_TransconductorApps

06-F10_TransconductorApps - EE 541 Lecture Aid #6 Fall...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
EE 541 Lecture Aid #6 Fall Semester 2010 Operational Transconductor Characteristics And Applications Dr. John Choma, Professor Of Electrical Engineering Ming Hsieh Department of Electrical Engineering Powell Hall Of Engineering (PHE) Room #620 University of Southern California University Park; Mail Code: 0271 Los Angeles, California 90089-0271 (213) 740-4692 [Office] johnc@usc.edu [E-Mail] www.jcatsc.com [Course Notes]
Background image of page 1

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

View Full DocumentRight Arrow Icon
EE 541 Lecture Aid #6 Operational Transconductor Applications 323 Overview Of Lecture O Circuit Fundamentals Of Transconductor Amplifiers O Miscellaneous Applications ± Open Loop Integrator ± Active Tunable Resistance ± Lowpass Tunable Amplifiers ± Gyrator-Based Active Inductors ± Impedance Transformers ± Quadrature Oscillator O Biquadratic Filters ± Filter Examples ² Lowpass ² Highpass ² Bandpass ² Notch ² Delay ± Generalized Architecture
Background image of page 2
EE 541 Lecture Aid #6 Operational Transconductor Applications 324 + V s R s C V o + G m Phase Inverting + V s R s C V o + G m Non-Phase Inverting + + V s R s C V o Active Integrator Circuits O Conventional Op-Amp Integrator ± Feedback Demands Op-Amp Pole Dominance ± Band-Limited By Op-Amp Compensation ± Unity Gain Frequency ( ω m ) Dependent On Source Resistance O Transconductor Integrator (OTA-C) ± Open Loop; No Feedback ± Better Frequency Response Than Op-Amp ± Unity Gain Frequency Independent Of Source Resistance O Unity Gain Frequency Is Set By Transconductance G m , Whose Value Can Be Controlled By Applied Bias Voltage Or Current om s s V ω 1 Vs R Cs =− omm s VG ω ±± ==
Background image of page 3

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

View Full DocumentRight Arrow Icon
EE 541 Lecture Aid #6 Operational Transconductor Applications 325 Operational Transconductor-Capacitor Integrator O Ideal Integrator ± Infinite Input Impedance ± Infinite Output Impedance ± 90º Relative Phase Shift O Integrator Circuit Parasitics ± Input Capacitance (C i ) ± Output Capacitance (C o ) ± Feedback Capacitance (C r ) ± Output Resistance (r o ) ± Operational Transconductor Amplifier-Capacitor Known As OTA-C z Design Objectives ± Negligible C r (Plausible For Multistage) ± Small Source Resistance, R s ± Very Large r o ± Dominant Net Output Capacitance omu s VG ω Vs Cs =− mo r o s 12 s Gr 1 z V V ss 11 p p ⎛⎞ ⎜⎟ ⎝⎠ ++ + V s R s C V o V o + G m Phase Inverting GV mi r o C o C r C C i + V s R s + V i
Background image of page 4
EE 541 Lecture Aid #6 Operational Transconductor Applications 326 OTA-C Transfer Relationships O Pole Dominance ± Set At Output Port ± Large r o ± Appended Capacitance, C O Error Function V o GV mi r o C o C r C C i + V s R s + V i ( ) oo 12 1 11 1 rC C pp p +≈ + m r r G z C = () s i s i 2 Rr C CC RC p =+ mo r o s s Gr 1 z V H(s) V ss p p ⎛⎞ ⎜⎟ ⎝⎠ == ++ u r u 1 2 ω s 1 sz ω ε (s) s p s sp =− r 1 2 s 1 z ε (s) p s ± m u o G ω = +
Background image of page 5

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

View Full DocumentRight Arrow Icon
EE 541 Lecture Aid #6 Operational Transconductor Applications 327 OTA-C Error Function O Error Function ± Ideally Is Unity For All Signal Frequencies ± Unity Approximation Requires: O
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/22/2011 for the course EE 541 at USC.

Page1 / 58

06-F10_TransconductorApps - EE 541 Lecture Aid #6 Fall...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online