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A new topology for designing low-voltage current feedback amplifiers (CFAs) is presented. By employing a second-generation positive current conveyor followed by an operational amplifier in an unconventional manner, the design circumvents the problem of trying to achieve large transimpedance in a low-voltage environment. It is shown that this CFA configuration also results in near gain independent closed-loop bandwidth defined by a single feedback resistor. The proposed amplifier was verified experimentally by a chip designed using Taiwan Semiconductor Manufacturing Company's 0.18-[micro]m digital CMOS process of a single-ended power supply of 1.8 V. Index Terms--Current feedback amplifier (CFA), low-voltage operational amplifier.

Summary: Measuring phase noise in oscillators is crucial in communication systems, vibration analysis, and frequency synthesizers. Traditionally, this measurement is done in frequency domain by estimating the ratio of the power density at an offset frequency from the carrier to the power of the carrier signal. This approach is hardware intensive and dependent on the the offset frequency, for which there exists no standard. Here, we propose an alternative method to quantify phase noise but in the time domain in the form of a root‐mean‐square true phase angle deviation. This is done using a self‐created reference signal and by applying the Hilbert transform to generate a complex analytic signal from the real time‐domain data sequence. This enables the computation of instantaneous metrics such as phase noise. Simulations and experimental results are provided to validate the proposed technique. In addition, its relationship to the origin of phase noise is mathematically explained. [ABSTRACT FROM AUTHOR]

This paper presents mathematical derivations for a type of maximum-likelihood sequence detector (MLSD), for decoding signals equalized to the ternary partial response fundamental polynomials--duobinary (1 + D) and dicode (1 - D); or part of decoders for higher-order class of partial response polynomials. Region-dependent but algorithmically directed thresholds with relatively simple updates for ternary duobinary (1 + D) and dicode (1 - D) channel decoders are hereby presented which depend only on state metric differences. The simplicity of the threshold updates makes the new proposition very attractive for hardware implementation. Derivations for a ternary duobinary and dicode partial-response signaling (PRS) channel decoder based on the true difference metric algorithm are included. Index Terms--Analog decoders, partial-response signaling (PRS), Viterbi algorithm.

This paper presents a comprehensive method and analysis on the design of two-transistor multi-output filters where three possible functions are simultaneously available. Although two transistors are employed at its core, proper biasing does not require additional passive components. A total of thirteen valid second-order filters are reported, and several of them are experimentally tested using discrete transistors as well as simulated using Spectre in a BiCMOS process. A fully differential realization of a MOS-C band-pass filter, based on one of the structures found, is designed and then used to realize a fourth-order Chebyshev band-pass filter. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]