Sampled-data modeling and dynamical effect of output-capacitor time-constant for valley voltage-mode controlled buck-boost converter

By analyzing the output voltage ripple of a buck-boost converter with large equivalent series resistance（ESR） of output capacitor, one valley voltage-mode controller for buck-boost converter is proposed. Considering the fact that the increasing and decreasing slopes of the inductor current are assumed to be constant during each switching cycle, an especial sampleddata model of valley voltage-mode controlled buck-boost converter is established. Based on this model, the dynamical effect of an output-capacitor time-constant on the valley voltage-mode controlled buck-boost converter is revealed and analyzed via the bifurcation diagrams, the movements of eigenvalues, the Lyapunov exponent spectra, the boundary equations,and the operating-state regions. It is found that with gradual reduction of output-capacitor time-constant, the buck-boost converter in continuous conduction mode（CCM） shows the evolutive dynamic behavior from period-1 to period-2, period-4, period-8, chaos, and invalid state. The stability boundary and the invalidated boundary are derived theoretically by stability analysis, where the stable state of valley voltage-mode controlled buck-boost converter can enter into an unstable state, and the converter can shift from the operation region to a forbidden region. These results verified by time-domain waveforms and phase portraits of both simulation and experiment indicate that the sampled-data model is correct and the time constant of the output capacitor is a critical factor for valley voltage-mode controlled buck-boost converter, which has a significant effect on the dynamics as well as control stability.

MISO-Type Voltage-Mode Universal Biquadratic Filter Using Single Universal Voltage Conveyor

A universal biquadratic filter using single universal voltage conveyor (UVC), two resistors and two capacitors is presented in this paper. The proposed structure has three inputs and one output and can realize all the five standard biquadratic filters: low-pass (LP), high-pass (HP), band-pass (BP), band-reject (BR) and all-pass (AP) from the same circuit configuration. The presented universal filter offers low active and passive sensitivities. SPICE (Version 16.5) simulation results using 0.18 μm TSMC technology have been included.

Voltage-Mode Universal Biquad Filter Employing Single Voltage Differencing Differential Input Buffered Amplifier

A new multi function voltage-mode universal biquadratic filter using single Voltage Differencing Differential Input Buffered Amplifier (VD-DIBA), two capacitors and one resistor is proposed. The proposed configuration has four inputs and one output and can realize all the five standard filters from the same circuit configuration. The presented biquad filter offers low active and passive sensitivities. The validity of proposed universal biquadratic filter has been verified by SPICE simulation using 0.35 μm MIETEC technology.

VDTA Based Electronically Tunable Voltage-Mode and Trans-Admittance Biquad Filter

In this paper, a biquad filter configuration based on two voltage differencing transconductance amplifiers (VDTAs) as newly active elements and only two capacitors as passive elements is proposed which can realize voltage-mode low pass (LP), band pass (BP), high pass (HP), band reject (BR) and all pass (AP) filtering responses using three voltage inputs. Simultaneously, the same configuration can also be used to obtain LP, BP and HP filtering responses in transadmittance-mode. The proposed biquad is capable of providing electronic control of quality factor independent of pole frequency through single transconductance parameter (biasing current). It also offers the advantage of low active and passive sensitivity. To support the theoretical analysis, the PSPICE simulation of the proposed circuit is done using 0.18 μm CMOS technology from TSMC.

CMOS VDIBAs-Based Single-Resistance-Controlled Voltage-Mode Sinusoidal Oscillator

In this communication, a new single-resistance controlled sinusoidal oscillator (SRCO) has been presented. The presented SRCO uses two voltage differencing inverting buffered amplifiers (VDIBAs), one resistor and two capacitors in which one is grounded (GC) and the other one is floating (FC). The proposed structure offers the following advantageous features: 1) independent control of oscillation condition (OC) and oscillation frequency (OF);2) low passive and active sensitivities and 3) very good frequency stability. The non-ideal effects of the VDIBA on the proposed oscillator have also been investigated. The proposed SRCO has been tested for its robustness using Monte-Carlo simulations. The check of the validity of the presented SRCO has been established by SPICE simulations using 0.18 μm TSMC technology.

Dual DVCC Based Voltage-Mode Digitally Programmable Biquadratic Filter

The recent advances in IC technology have led to the trend of designing hybrid systems to benefit both analog and the digital domain. Among analog circuits, multifunctional filter along with multiphase oscillator constitutes a building block of critical importance. In this paper, a digitally reconfigurable multi-input-multi-output voltage mode multifunctional biquadratic filter has been presented. The circuit comprises of two differential voltage current conveyors (DVCCs), two grounded capacitors and two floating resistors. The digital controllability is incorporated using a current-summing network (CSN). Tunability of quality factor is achieved by the use of a 3-bit digital control word while keeping the resonant frequency constant. PSPICE simulations using TSMC 0.25 μm CMOS technology have been performed to validate the theoretically predicted results.

A New Voltage-Mode Universal Biquadratic Filter Using Single UVC

The paper presents a new universal biquadratic filter using single universal voltage conveyor (UVC), two resistors and two capacitors. The offered structure has three inputs and one output and can realise all the five basic biquadratic filters: high-pass (HP), low-pass (LP), band-reject (BR), band-pass (BP) and all-pass (AP) from the same circuit topology. The proposed universal filter also provides following advantageous features, not available simultaneously in any UVC based universal biquadratic filter so far: (i) low active and passive sensitivities, (ii) independent control of natural frequency (ω0) and bandwidth (BW) and (iii) no requirement of any component matching condition and inversion of input signal(s) (as needed in most of the earlier reported structures). The workability of proposed structure has been presented by SPICE (Version 16.5) simulation using 0.18 μm TSMC technology.

Voltage-Mode Third-Order Quadrature Sinusoidal Oscillator Using VDBAs

This paper presents a third-order quadrature sinusoidal oscillator (TOQSO) using two voltage differencing buffered amplifiers (VDBAs), three capacitors and a resistor. The new topology provides two quadrature voltage outputs. The condition of oscillation (CO) and frequency of oscillation (FO) are electronically independently controllable by the separate transconductance of the VDBAs. The workability of the proposed TOQSO is confirmed by SPICE (Version 16.5) simulation using Taiwan semiconductor manufacturing company (TSMC) 0.18 μm process parameters.

Versatile Voltage-Mode Universal Filter Using Differential Difference Current Conveyor

A novel four-input three-output voltage-mode differential difference current conveyor (DDCC) based universal filter is presented. The circuit uses three DDCCs as active elements, two resistors and two capacitors as passive elements. The circuit along with its versatility enjoys the advantage of minimum number of passive elements employment. SPICE simulation results are given to confirm the theoretical analysis. The proposed circuit is a novel addition to the existing knowledge on the subject.

Voltage-Mode Lowpass, Bandpass and Notch Filters Using Three Plus-Type CCIIs

A single input and three outputs voltage-mode biquadratic filter using three plus-type second-generation current conveyors (CCII), two grounded capacitors and five resistors is presented. The proposed circuit offers the following features: realization of three filter functions, which are, lowpass, bandpass and notch filters, simultaneously, the use of only grounded capacitors. PSPICE simulation results are also included.

A low-power high-swing voltage-mode transmitter

A low-power voltage-mode-logic （VML） transmitter fabricated in TSMC 28 nm CMOS technology is presented. The VML driver outputs a high-swing signal and consumes less power than a current-mode-logic （CML） driver. To further reduce power, the driver is divided into two voltage domains by level shifters. Moreover, the proposed driver topology can achieve mutually decoupled impedance self-calibration and equalization control. The measurement result shows that the transmitter merely dissipates 23 roW/channel while exhibiting an 880 mV differential eye height at 4.488 Gb/s.

A voltage-mode DC–DC buck converter with fast output voltage-tracking speed and wide output voltage range

A high switching frequency voltage-mode buck converter with fast voltage-tracking speed and wide output voltage range has been proposed. A novel error amplifier （EA） is presented to achieve a high DC gain and get high phase margin, including a resistor and capacitor net, a unit gain block and a high gain block. The investigated converter has been fabricated with GF 0.35 μm CMOS process and can operate at 6 MHz with the output voltage range from 0.6 to 3.4 V. The experimental results show that the voltage-tracking speed can achieve 8.8 μs/V for up-tracking and 6 μs/V for down-tracking. Besides, the recovery time is less than 8 μs while the load current suddenly changes 400 mA.

Voltage/Current-Mode Multifunction Filters Using One Current Feedback Amplifier and Grounded Capacitors

One configuration for realizing voltage-mode multifunction filters and another configuration for realizing current-mode multifunction filters using current feedback amplifiers (CFAs) are presented. The proposed voltage-mode circuit exhibit simultaneously lowpass and bandpass filters. The proposed current-mode circuit exhibit simultaneously lowpass, bandpass and highpass filters. The proposed circuits offer the following features: no requirements for component matching conditions;low active and passive sensitivities;employing only grounded capacitors and the ability to obtain multifunction filters from the same circuit configuration.

Fully Uncoupled Electronically Controllable Sinusoidal Oscillator Employing VD-DIBAs

Recently, voltage differencing-differential input buffered amplifiers (VD-DIBA)-based electronically controllable sinusoidal oscillator has been presented that it does not have the capability of complete independence of frequency of oscillation (FO) and condition of oscillation (CO) as well as electronic control of both CO and FO. In this article, a new fully-uncoupled electronically controllable sinusoidal oscillator using two VD-DIBAs, two grounded capacitors and two resistors has been proposed which offers important advantages such as 1) totally uncoupled and electronically controlled condition of oscillation (CO) and frequency of oscillation (FO);2) low active and passive sensitivities;and 3) a very good frequency stability factor. The effects of non-idealities of the VD-DIBAs on the proposed oscillator are also investigated. The validity of the proposed formulation has been confirmed by SPICE simulation with TSMC 0.18 μm process parameters.

New VD-DIBA-Based Single-Resistance-Controlled Sinusoidal Oscillator

A new Single-Resistance-Controlled (SRC) sinusoidal oscillator using single Voltage Differencing-Differential Input Buffered Amplifier (VD-DIBA), only four passive components (two capacitors and two resistors), is presented. The proposed structure provides the following advantageous features: 1) independent control of oscillation frequency and condition of oscillation and 2) low active and passive sensitivities. The effects of non-idealities of the VD-DIBA on the proposed oscillator have also been investigated. The proposed SRC sinusoidal oscillator has been checked for robustness using Monte-Carlo simulation. SPICE simulation results have been included using 0.35 μm MIETEC technology to confirm the validity of the proposed SRC sinusoidal oscillator.

Electronically Controllable Quadrature Sinusoidal Oscillator Using VD-DIBAs

A new voltage-mode quadrature sinusoidal oscillator (QSO) using two voltage differencing-differential input buffered amplifiers (VD-DIBAs) and only three passive components (two capacitors and a resistor) is presented. The proposed QSO circuit offers advantages of independent electronic control of both oscillation frequency and condition of oscillation, availability of two quadrature voltage outputs and low active and passive sensitivities. SPICE simulation results have been included using 0.35 μm MIETEC technology to confirm the validity of the proposed QSO oscillator.

VDTA-Based Wave Active Filter

In this paper we present a wave active filter based on Voltage Differencing Transconductance Amplifiers (VDTAs). The synthesis of active filters basically based on processing of wave quantities. The wave method is presented for basic building blocks of active filters i.e. a series inductor and parallel capacitor through which realization of various active circuits is made by appropriate connections. The proposed wave active filter is verified by realizing a 4th order low pass Butterworth filter using SPICE simulation with 0.18 μm TSMC CMOS technology parameters.

New Voltage Mode Sinusoidal Oscillator Using Voltage Differencing Transconductance Amplifiers (VDTAs)

The purpose of this paper is to introduce a new electronically controlled voltage mode sinusoidal oscillator (VMSO) using Voltage Differencing Transconductance Amplifiers (VDTA). The proposed circuit provides electronic control of ω0 and independent condition of oscillation (CO). It is found that the oscillator works very satisfactorily and pure sinusoidal waveforms are available at the outputs. The PSPICE simulation confirms the theoretical results. The proposed oscillator circuit employs only two VDTAs, along with two grounded capacitor and single grounded resistor. The circuit exhibits low active and passive sensitivities for ω0. Simulation results are obtained by using PSPICE software with TSMC CMOS 0.18 um process parameters.

Realization of a New Current Mode Second-Order Biquad Using Two Current Follower Transconductance Amplifiers (CFTAs)

A new circuit for realization of universal current-mode filter using current Follower Transconductance Amplifiers (CFTAs) is presented. The proposed circuit realizes current-mode low pass, high pass and band pass filter functions simultaneously with a single current source at the input. The band reject and all pass filters can also be obtained from the proposed circuit without any extra hardware. The proposed circuit employs three passive grounded elements and two CFTAs. Linear electronic control of natural frequency ω0 is available in the proposed circuit. The quality factor can be independently adjusted through grounded resistor. The proposed circuit employs two grounded capacitors and a grounded resistor along with two CFTAs. The grounded resistor can be replaced by an OTA based circuit for linear electronic control of quality factor Q0. The circuit exhibits low active and passive sensitivities for ω0 and Q0. Simulation results are obtained using PSPICE software which is in conformity with the theoretical findings.

Precision Full-Wave Rectifier Using Two DDCCs

A new precision full-wave rectifier employing only two differential difference current conveyors, which is very suitable for CMOS technology implementation, is presented. The proposed rectifier is the voltage-mode circuit, which offers high-input and low-output impedance hence it can be directly connected to load without using any buffer circuits. PSPICE is used to verify the circuit performance. Simulated rectifier results based-on a 0.5 μm CMOS technology with ±2.5 V supply voltage demonstrates high precision rectification and excellent temperature stability. In addition, the application of proposed rectifier to pseudo RMS-to-DC conversion is also introduced.