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A high-performance current-mode, multi-input winner-take-all maximum circuit is introduced. Owing to low-impedance low-capacitance input nodes involved, the speed of the new circuit is higher than major counterparts. Simulation results show that the new circuit exhibits superior performance compared with well-known rival counterparts in terms of speed, area, dynamic range and power dissipation.

An innovative theory on the passive circuits capable to generate low-pass negative group delay (NGD) behaviour is introduced. An identification method enabling to identify the first-order NGD simple cells built with resistor-inductor (RL)- and resistor-capacitor (RC)-networks is elaborated. The fundamental characteristics as the NGD level and cut-off frequency are formulated from the low-pass NGD circuit canonical transfer function. The NGD existence conditions are derived in function of the established topology parameters. Despite the attenuation systematically related to the passive cell nature, low-pass NGD behaviours with tens ns NGD level and tens MHz bandwidth were obtained with an example of lumped RL-network-based L-topology circuit. Transient analysis was performed to illustrate that the NGD phenomenon enables to exhibit baseband signal advance effect. The proposed NGD topology simplicity promises their potential applications especially in term of signal correction and the modern electronic system improvement.

The operation of a self-oscillating switched-mode circuit topology for low-voltage thermal energy harvesting is analysed and experimental efficiency results are presented. Circuit self-start-up function as well as high-efficiency power transfer are obtained by using only one transformer without additional inductors. It is shown that even without using a maximum power point tracking (MPPT) tracking circuit, it is possible to achieve efficiencies up to 65% over a relatively broad input voltage range which can be optimised by properly varying the transformer turns ratio n.

A reliable and methodical solution to restrain transient undershoot on VS pin for a high-voltage gate drive circuit with a transient negative voltage detector circuit (TNVDC) is proposed. The proposed TNVDC circuit does not consume any quiescent current while the chip works normally and it is totally integrated in a high-voltage integrated circuit (HVIC) without any additional discrete devices in the system. The proposed circuit could send a control signal to the drive stage of the HVIC for decreasing the sink current while the transient undershoot of the VS is excessive. The measurement shows that the negative voltage surge tolerance is −98 V of the HVIC with TNVDC.

Presented is a modified parallel-circuit class-E amplifier that operates above the theoretical maximum frequency, recovering the class-E operating conditions. The finite inductor in the parallel circuit topology is replaced by a more suitable network composed of four transmission lines. The theory formula of the circuit elements of the proposed network is derived in detail, and an example is designed and measured to validate the analysis. The measured maximum output power of 40 dBm, drain efficiency of 77.5%, and power-added efficiency of 70.8% at 2.8 GHz were obtained, showing excellent efficiency compared to that obtained by other amplifiers using the same device.

An on-chip CMOS current-sensing circuit for a DC-DC buck converter is presented. The circuit can measure the inductor current through sensing the voltage of the switch node during the converter on-state. By matching the MOSFETs, the achieved sense ratio is almost independent of temperature, model and supply voltage. The proposed circuit is suitable for low power DC-DC applications with high load current.

A new current-mode multi-input looser-take-all minimum circuit is presented. The circuit has very compact and simple architecture with only three transistors per input. It is shown that the proposed circuit exhibits better performance and is more robust to parametric variations compared to its previous counterparts.

A method to implement a square-rooting circuit is described. The proposed circuit employs operational transconductance amplifiers (OTAs) as the only active elements. The implementation technique is based on an electronically variable resistor formed by the OTA, where the magnitude of the resistance is controlled by the output current, to provide the square-rooting function. The proposed scheme can operate with both a voltage input and a current input signal. The purpose of the circuit is emphasised in terms of simple configuration, high accuracy and low cost. Experimental results showing the circuit performance are presented.

A low-voltage pseudo-differential double-sampled track-and-hold circuit with low hold pedestal based on the Miller-effect scheme is proposed. Rail-to-rail operation of bootstrapped switches allows the low-voltage T/H circuit implementation. Simulation results confirm that the proposed circuit is effective in low-voltage applications with low hold pedestal.

A full-wave equivalent circuit model for any arbitrary 2D conductor has been developed. The SPICE-compatible full-wave circuit model could be easily integrated into any circuit-based simulator to study the influence of any conductor on high-speed circuit performance.

A new current-mode multiple input maximum circuit designed with 2n+1 transistors for n inputs is proposed. The output impedance of this circuit is the same order as that of a Wilson current source. This circuit has been fabricated using 0.8 mu m CMOS technology. The experimental result has verified the function of the circuit and shown the merit of high speed and high accuracy.

A nonlinear circuit driven by a square wave voltage source and comprising a series combination of a resistor, capacitor and nonlinear inductor, whose core displays saturation and hysteresis, is realistically modelled for the first time. Period multiplication and chaos are observed and excellent agreement is obtained between experiment and simulation.

Median filters are very important nonlinear filters, finding many applications in image and speech processing. A novel CMOS analogue median circuit is proposed with a design that employs a combination of current-mode circuits such as a current absolute value circuit and a current minimum circuit.

A temperature stable external reference resistor is used to accurately control and tune the transconductance of an integrated current-mirror. The technique can be used to tune and optimise the bandwidth of the current-mirror for application in CMOS filters.

A current-mode divide-by-two circuit is presented which does not rely on well matched components and a high gain opamp. The circuit can be employee as a reference-generating circuit of an algorithmic current-mode A/D convertor.< >

A new skin effect equivalent circuit and a propagation line equivalent circuit for time domain simulation on a single line have been presented in previous work (T. Vu Dinh et al., 1990) SPICE simulations have proved the accuracy and efficiency of the proposed method. This concept is extended for coupled line modelling. A dual line device is analysed as a typical example of the usual cases. The method has successfully been extended to N lossy coupled lines. The results show a good agreement with those obtained by other methods. >

A relationship is obtained for the nonsingular T transformation that exists between two minimal realisations of the state equations and the Howitt transformation between the corresponding 2-element-kind networks. It is proved that the Howitt transformation can generate all the passive minimal RC or RL equivalent networks that can be generated by the nonsingular T transformation.

The letter presents a simple new circuit for the correction of amplitude deviations arising from the sample-and-hold effect in switched-capacitor filters. The new circuit is first-order and is connected in cascade at the output of the filter. Unlike a previous circuit, the new circuit is stray-free and has a bi-linera transfer function. Design information is given in the form of a table.

A simple circuit that gives a linear relation between input DC control voltage and an average load voltage is described. This circuit depends on a simple vector difference circuit based on inverse sine evaluation. The load voltage is found to be independent of the supply line voltage and of frequency fluctuations.

The d.c. behaviour of the negative-impedance circuit, including temperature effects, is explained. The frequency behaviour is shown by means of an equivalent circuit. Linearity as a function of the frequency and the direct current is given in graphical form. This negative-impedance circuit is shown to be preferable in many respects to existing ones. Frequency-selective filter-amplifier circuits are described.

A set of three conditions which are necessary and sufficient for the RC: RL decomposition of a 4th-order polynomial is derived. The conditions are expressed in terms of the Qs and the coefficients of each quadratic factor, and the method thus offers a computational advantage over a previous method.

The relative circuit gain of two configurations of common-emitter antisaturation-feedback circuit is derived as a function of circuit parameters.