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1 – 10 of over 2000Reza Chavoshisani, Mohammad Hossein Moaiyeri and Omid Hashemipour
Current-mode approach promises faster and more precise comparators that lead to high-performance and accurate winner-take-all circuits. The purpose of this paper is to present a…
Abstract
Purpose
Current-mode approach promises faster and more precise comparators that lead to high-performance and accurate winner-take-all circuits. The purpose of this paper is to present a new high-performance, high-accuracy current-mode min/max circuit for low-voltage applications. In addition, the proposed circuit is designed based on a new efficient high-resolution current conveyor-based fully differential current comparator.
Design/methodology/approach
The proposed design detects the min and max values of two analog current signals by means of a current comparator and a logic module. The comparator compares the values of the input current signals accurately and generates two digital control signals and the logic module determines the min and max values based on the controls signals. In addition, an accurate current copy module is utilized to copy the input current signals and convey them to the comparator and the logic module.
Findings
The results of the comprehensive simulations, conducted using HSPICE with the TSMC 90 nm CMOS technology, demonstrate the high-performance and robust operation of the proposed design even in the presence of process, temperature, input current and supply voltage variations. For a case in point, for 5 μA differential input current the average propagation delay and power consumption of the proposed circuit are attained as 150 ps and 150 µW, respectively, which leads to more than 64 percent improvement in terms of power-delay product as compared with the most efficient design, previously presented in the literature.
Originality/value
A new efficient structure for current-mode min-max circuit is proposed based on a novel current comparator design which is accurate, high-performance and robust to process, voltage and temperature variations.
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Keywords
Mohammad Faseehuddin, Norbert Herencsar, Musa Ali Albrni, Sadia Shireen and Jahariah Sampe
Abstract
Purpose
This paper aims to achieve two main objectives. First, to introduce to the literature a new versatile active building block, namely, voltage differencing differential voltage current conveyor (VD-DVCC) for analog signal processing applications. Second, to design a novel electronically tunable mixed-mode universal filter. The designed filter provides low-pass, high-pass, band-pass, band-reject and all-pass responses in voltage-mode (VM), current-mode (CM), trans-impedance-mode (TIM) and trans-admittance-mode (TAM).
Design/methodology/approach
The proposed filter uses two VD-DVCCs, three resistors and two capacitors. All the capacitors used are grounded, which is advantageous from the monolithic integration point of view. The VD-DVCC is designed and validated in Cadence software using CMOS 0.18 µm process design kit from Silterra Malaysia at a supply voltage of ±1 V.
Findings
The proposed novel filter enjoys many attractive features including as follows: the ability to operate in all four modes, no requirement of capacitive matching, tunability of quality factor (Q) independent of pole frequency, availability of both inverting and non-inverting outputs for VM and TIM mode, high output impedance explicit current output for CM and TAM, no requirement for double/negative input signals (voltage/current) for response realization and low active and passive sensitivities. The filter is designed for a pole frequency of 5.305 MHz. The obtained results bear a close resemblance with the theoretical findings.
Originality/value
The proposed novel filter structure requires a minimum number of active and passive components and provides operation in all four operating modes. The filter will find application in structures of mixed-mode systems.
Details
Keywords
To provide new structures and applications of CCII for analog signal processing.
Abstract
Purpose
To provide new structures and applications of CCII for analog signal processing.
Design/methodology/approach
New structure and new applications suitable for low voltage analog signal processing.
Findings
These structures developed for CCII can be used in development for future low voltage applications.
Research limitations/implications
Structures cannot be realized due to unavailability of funding at place of research.
Practical implications
Can be useful information for future low voltage analog designs.
Originality/value
The paper presents new ideas for CCII applications.
Details
Keywords
Mehdi Habibi, Yunus Dawji, Ebrahim Ghafar-Zadeh and Sebastian Magierowski
Nanopore-based molecular sensing and measurement, specifically DNA sequencing, is advancing at a fast pace. Some embodiments have matured from coarse particle counters to enabling…
Abstract
Purpose
Nanopore-based molecular sensing and measurement, specifically DNA sequencing, is advancing at a fast pace. Some embodiments have matured from coarse particle counters to enabling full human genome assembly. This evolution has been powered not only by improvements in the sensors themselves, but also in the assisting microelectronic CMOS readout circuitry closely interfaced to them. In this light, this paper aims to review established and emerging nanopore-based sensing modalities considered for DNA sequencing and CMOS microelectronic methods currently being used.
Design/methodology/approach
Readout and amplifier circuits, which are potentially appropriate for conditioning and conversion of nanopore signals for downstream processing, are studied. Furthermore, arrayed CMOS readout implementations are focused on and the relevant status of the nanopore sensor technology is reviewed as well.
Findings
Ion channel nanopore devices have unique properties compared with other electrochemical cells. Currently biological nanopores are the only variants reported which can be used for actual DNA sequencing. The translocation rate of DNA through such pores, the current range at which these cells operate on and the cell capacitance effect, all impose the necessity of using low-noise circuits in the process of signal detection. The requirement of using in-pixel low-noise circuits in turn tends to impose challenges in the implementation of large size arrays.
Originality/value
The study presents an overview on the readout circuits used for signal acquisition in electrochemical cell arrays and investigates the specific requirements necessary for implementation of nanopore-type electrochemical cell amplifiers and their associated readout electronics.
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T. Parveen, S.S. Rajput and M.T. Ahmad
Aims to present a new low voltage CCII‐based high frequency performance voltage mode multifunctional filter, which can realize standard biquadratic low pass, band pass and high…
Abstract
Purpose
Aims to present a new low voltage CCII‐based high frequency performance voltage mode multifunctional filter, which can realize standard biquadratic low pass, band pass and high pass functions through appropriate selection of admittances.
Design/methodology/approach
Describes the filter which consists of a CMOS plus type CCII along with five passive components out of which four components are grounded while one is floating.
Findings
Simulation results indicate matching between theoretical and simulated performances over a wide dynamic range.
Originality/value
Provides simulation results that confirm the excellent performance of a multifunctional CCII+ filter.
Details
Keywords
Chiemeka Loveth Maxwell, Dongsheng Yu and Yang Leng
The purpose of this paper is to design and construct an amplitude shift keying (ASK) modulator, which, using the digital binary modulating signal, controls a floating memristor…
Abstract
Purpose
The purpose of this paper is to design and construct an amplitude shift keying (ASK) modulator, which, using the digital binary modulating signal, controls a floating memristor emulator (MR) internally without the need for additional control circuits to achieve the ASK modulated wave.
Design/methodology/approach
A binary digital unipolar signal to be modulated is converted by a pre-processor circuit into a suitable bipolar modulating direct current (DC) signal for the control of the MR state, using current conveyors the carrier signal’s amplitude is varied with the change in the memristance of the floating MR. A high pass filter is then used to remove the DC control signal (modulating signal) leaving only the modulated carrier signal.
Findings
The results from the experiment and simulation are in agreement showed that the MR can be switched between two states and that a change in the carrier signals amplitude can be achieved by using an MR. Thus, showing that the circuit behavior is in line with the proposed theory and validating the said theory.
Originality/value
In this paper, the binary signal to be modulated is modified into a suitable control signal for the MR, thus the MR relies on the internal operation of the modulator circuit for the control of its memristance. An ASK modulation can then be achieved using a floating memristor without the need for additional circuits or signals to control its memristance.
Details
Keywords
T. Parveen and M.T. Ahmed
Aims to present a simple circuit for the realization of electronically tunable ideal grounded inductor, which consists of two current controlled conveyors along with a grounded…
Abstract
Purpose
Aims to present a simple circuit for the realization of electronically tunable ideal grounded inductor, which consists of two current controlled conveyors along with a grounded capacitor. Also its application for realization of multifunctional filter is demonstrated.
Design/methodology/approach
Multifunctional filter (low pass, band pass and high pass filters) is designed using proposed grounded inductor realization which provides standard responses without any constrains in terms of matching conditions.
Findings
The multifunctional filter designed using the proposed realization has many attractive features such as low component count, high‐Q, low sensitivity performance, independent Q‐tuning of the filter without affecting its pole frequency.
Originality/value
Simulation results show excellent performance with low power consumption of 1.87 mW at ±2.5 supply voltage.
Details
Keywords
Hongying Shan, Mengyao Qin, Cungang Zou, Peiyang Peng and Zunyan Meng
To respond to customer needs and achieve customized manufacturing, the manufacturing industry, as represented by electronics assembly companies, has embarked on a path of business…
Abstract
Purpose
To respond to customer needs and achieve customized manufacturing, the manufacturing industry, as represented by electronics assembly companies, has embarked on a path of business model transformation (customer to manufacturer [C2M]). The purpose of this paper is to examine the practical application of assembly line-Seru conversion in a Chinese electronics assembly company during the C2M transition.
Design/methodology/approach
To begin with, this paper proposed a production line improvement scheme suitable for the conversion of C2M manufacturing enterprise assembly line-Seru based on an analysis of the difficulties encountered in the existing production line of A company in China. Then, a mathematical model was presented for the minimum value of the makespan and the maximum workers’ expenditure between Serus. Finally, the SA-NSGA-II algorithm and the entropy-weight TOPSIS approach were used to determine the optimal scheme for Seru unit, batch, product type and worker distribution.
Findings
Seru production and multiskilled workers are more suited to the C2M business model. The most effective strategy for worker allocation can reduce the number of employees and makespan in Serus. Additionally, the performance of the SA-NSGA-II algorithm and the method of selecting the optimal solution from the Pareto solution by the entropy-weighted TOPSIS method is also demonstrated.
Practical implications
Through a detailed study of how to transform the production line, other companies can apply the methods outlined in this article to shorten the delivery time, make full use of the abilities of workers and assign workers to specific positions, thereby reducing the number of workers, workers’ expenditure and improving the balance rate of production lines.
Originality/value
Given the scarcity of studies on the production method of C2M-type firms in the prior literature, this paper examined the assembly line-Seru conversion problem with the goal of minimizing the makespan and worker expenditure. To address the NSGA-II algorithm’s insufficient convergence, the simulated annealing process is incorporated into the method, which improves the optimization performance.
Details
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A central problem of industrial robotics today is the development of systems for real‐world automatic assembly operations. Research groups in the US, UK, and Japan are currently…
Abstract
A central problem of industrial robotics today is the development of systems for real‐world automatic assembly operations. Research groups in the US, UK, and Japan are currently taking a systems approach to computer‐controlled manipulation and are emphasizing hand/sensor/assembly‐task interactions. This paper surveys memory + sensory control prototypes and eye‐hand coordination prototypes at IBM, University of Nottingham, Hitachi, and Mitsubishi.
The purpose of this paper is to present two new follower‐based current‐mode multifunction filters. Each of the proposed circuits can realize highpass, bandpass and lowpass…
Abstract
Purpose
The purpose of this paper is to present two new follower‐based current‐mode multifunction filters. Each of the proposed circuits can realize highpass, bandpass and lowpass filters, simultaneously.
Design/methodology/approach
The input terminals of the proposed current‐mode biquadratic filters are virtual grounded. The output terminals of the proposed circuits can be easily cascaded with the similar sections.
Findings
Highpass, bandpass and lowpass filters can be obtained simultaneously from the proposed circuits using only one or two followers.
Originality/value
The paper presents new ideas for follower applications.
Details