Class-E amplifier has the potential to deliver high efficiency required for the next generation wireless systems. In this journal, we discuss a novel load pull analysis technique to characterize the efficiency performance of Class-E amplifier in an outphasing power combining scheme. Class-E amplifier is not an ideal current or voltage source as is required for the traditional analysis of outpha...

An analytical modelling approach for fully differential amplifiers is presented and validated through examples. Separation of the analysis into two steps coupled with linear superposition techniques leads to concise mathematical expressions. An added benefit of the two-step approach is that the usual symmetry assumptions are not needed. As a consequence, the results hold for arbitrary element v...

Howland circuits have been widely used as powerful source for exciting tissue over a wide frequency range. When a Howland source is designed, the components are chosen so that the designed source has the desired characteristics. However, the operational amplifier limitations and resistor tolerances cause undesired behaviors. This work proposes to take into account the influence of the random di...

This paper presents a dynamic range boosting technique for wireless optical receivers. This technique changes the feedback impedance of the transimpedance amplifier by the control of multiple parallel transistors in the triode region. This strategy results on a wide controllable gain amplifier, without extra signalto-noise ratio penalties. A front-end with 20MHz bandwidth, maximum transimpedanc...

Using a nonlinear black-box model based on the Volterra theory it is possible to describe the nonlinear behavior of a high frequency amplifier. Acquiring only a strongly reduced set of measurements it is easy to predict the load impedance curves anywhere on a Smith Chart. The classic load-pull approach involves the acquisition of a large amount of data and still lacks a description of the nonli...

In this paper, a low power and high CMRR Instrumentation Amplifier is presented. It has been designed for use in Bio-Impedance (BI) applications that operate within the beta dispersion frequency range. An IA with a high CMRR and input impedance allows the extraction of the low amplitude BI signal while reducing the error signals and noise associated with the tissue and instrument interface. The...

Our findings indicate that the impedance cardiogram spectrum extends from DC to 50 Hz. Any amplifier with an upper band limit less than 50 Hz can be expected to produce attenuation and distortion of the impedance cardiogram. This signal attenuation may be systematically enhanced under conditions of high heart rate when a greater proportion of signal energy will be in the upper frequency range o...

Four-terminal impedance meters based on pseudo-bridges yield unexpected uncertainties when using high-contact-impedance electrodes. Adding a front-end amplifier to the impedance meter and rearranging the connection of the meter terminals overcome the contact impedance problem. However, because the compensation provisions in the instrument are meant to compensate only impedance residuals of test...

The dipolar method associated with a nonlinear time domain simulation program make up a powerful tool to analyze high Q-factor circuits like quartz crystal oscillators. After a brief remainder of the dipolar method, the paper will attempt to identify the main amplifier characteristics such as limitation mechanism, input and output impedances, etc. and to point out their influence on the amplifi...

This paper reports the design of a highly-linear CMOS amplifier for Variable Gain Amplifier (VGA) applications. A better than –60dB 3rd harmonic distortion at differential output level of 1V peak-to-peak is obtained by utilizing a linearization scheme that does not rely on the active devices. The amplifier maintains 3dB bandwidth over 300MHz. A noise figure at 8.6dB is obtained with source impe...