Compensated Current Injection circuit, theory and applications

This paper presents a detailed description, analysis and example of practical application of a wide frequency band voltage-to-current converter. The converter is characterized by a combination of positive and negative feedback loops. This feature allows compensation for parasitic impedance connected in parallel with the useful load, which in turn keeps an excitation current flowing through the useful load independent of its impedance. The simplicity of the circuit and its good electrical properties are additional advantages of the scheme.Comment: 9 pages and 7 figures in one PDF fil

Operational amplifiers for use in nuclear spectroscopy

Operational amplifiers for nuclear spectroscop

Comparative analysis of VDMOS/LDMOS power transistors for RF amplifiers

A comparison between the RF performance of vertical and lateral power MOSFETs is presented. The role of each parasitic parameter in the assessment of the power gain, 1-dB compression point, efficiency, stability, and output matching is evaluated quantitatively using new analytical expressions derived from a ten-element model. This study reveals that the contribution of the parasitic parameter on degradation of performance depends upon the specific technology and generic perceptions of source inductance and feedback capacitance in VDMOS degradation may not always hold. This conclusion is supported by a detailed analysis of three devices of the same power rating from three different commercial vendors. A methodology for optimizing a device technology, specifically for RF performance and power amplifier performance is demonstrated

Distributed Integrated Circuits: An Alternative Approach to High-Frequency Design

Distributed integrated circuits are presented as a methodology to design high-frequency communication building blocks. Distributed circuits operate based on multiple parallel signal paths working in synchronization that can be used to enhance the frequency of operation, combine power, and enhance the robustness of the design. These multiple signal paths usually result in strong couplings inside the circuit that necessitate a treatment spanning architecture, circuits, devices, and electromagnetic levels of abstraction

Very high frequency CMOS OTA-C quadrature oscillators

An approach to the design of high-frequency monolithic voltage-controlled oscillators using operational transconductance amplifiers and capacitors is given. Results from two 3 μm CMOS prototypes are presented. Both frequency and amplitude of the oscillations can be tuned by means of control voltages. Programmable oscillator frequencies up to 56.1 MHz are obtained, and the amplitudes are adjustable between 1 V peak-to-peak and 100 mV peak-to-peak. Total harmonic distortions from 2.8% down to 0.2% were experimentally measured

Progress of analog-hybrid computation

Review of fast analog/hybrid computer systems, integrated operational amplifiers, electronic mode-control switches, digital attenuators, and packaging technique