Dynamic Translinear and Log-Domain Circuits - Mulder, Jan

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Résumé :
Log-domain and translinear filters provide a competitive alternative to the challenges of ever increasing low-voltage, low-power and high frequency demands in the area of continuous-time filters. Since translinear filters are fundamentally large-signal linear, they are capable of realizing a large dynamic range in combination with excellent tunability characteristics. Large-signal linearity is achieved by exploiting the accurate exponential behavior of the bipolar transistor or the subthreshold MOS transistor. A generalization of the dynamic translinear principle exploiting the square law behavior of the MOS transistor is theoretically possible, but not practically relevant. Translinear and log-domain filters are based on the dynamic translinear principle, a generalization of the conventional (static) translinear principle. Besides their application for linear filters, dynamic translinear circuits can also be used for the realization of non-linear dynamic functions, such as oscillators, RMS-DC converters and phase-locked loops. Dynamic Translinear and Log-Domain Circuits: Analysis and Synthesis covers both the analysis and synthesis of translinear circuits. The theory is presented using one unifying framework for both static and dynamic translinear networks, which is based on a current-mode approach. General analysis methods are presented, including the large-signal and non-stationary analysis of noise. A well-structured synthesis method is described greatly enhancing the designability of log-domain and translinear circuits. Comparisons are made with respect to alternative analysis and synthesis methods presented in the literature. The theory is illustrated and verified by various examples and realizations. Dynamic Translinear and Log-Domain Circuits: Analysis and Synthesis is an excellent reference for researchers and circuit designers, and may be used as a text for advanced courses on the topic.

Sommaire:
1 Introduction.- 2 Design principles.- 2.1 A general approach to companding.- 2.2 Translinear principles based on the exponential law.- 2.3 Voltage-translinear principles based on the square law.- 3 Analysis of translinear circuits.- 3.1 Analysis of static translinear circuits.- 3.2 Analysis of dynamic translinear circuits.- 3.3 Characteristics of different translinear filter classes.- 4 Synthesis of translinear circuits.- 4.1 Overview of the synthesis method.- 4.2 Translinear transfer functions.- 4.3 Definition of capacitance currents.- 4.4 Translinear function decomposition.- 4.5 Hardware implementation.- 4.6 Alternative synthesis methods for dynamic translinear circuits.- 4.7 Class-AB operation.- 5 Device non-idealities.- 5.1 Base currents.- 5.2 Parasitic resistances.- 5.3 Body effect.- 5.4 Early effect.- 5.5 Parasitic capacitances.- 5.6 Mismatch.- 6 Noise.- 6.1 Definitions of dynamic range and signal-to-noise ratio.- 6.2 Transistor noise sources.- 6.3 Noise in non-linear circuits.- 6.4 Noise in static translinear circuits.- 6.5 Noise in translinear filters.- 7 Voltage-translinear circuits.- 7.1 Square law conformance.- 7.2 Designability.- 7.3 Analysis of dynamic voltage-translinear circuits.- 7.4 Characteristics of different voltage-translinear filter classes.- 8 Realisations.- 8.1 Subthreshold MOS translinear circuits.- 8.2 A translinear integrator for audio filter applications.- 8.3 A 1-volt class-AB translinear integrator.- 8.4 A dynamic translinear RMS-DC converter.- 8.5 A 3.3-volt current-controlled voltage-translinear oscillator.- 9 Conclusions.- A Additional design examples.- A.1 A syllabic companding translinear filter.- A.1.1 Distortionless syllabic companding.- A.1.2 Translinear implementation.- A.1.3 Simulation results.- A.2 A harmonic mean class-AB integrator.- A.2.1 Capacitance currents.- A.2.2 Design of the integrator.- A.3 A second-order low-pass filter.- A.3.1 Design of the filter.- A.3.2 Simulation results.