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This paper aims to model the coupled on-chip Copper (Cu) interconnects by using the multiresolution time-domain (MRTD) method.

The proposed model is a wavelet-based numerical method for analyzing signal integrity and propagation delay of coupled on-chip interconnects. Moreover, the dependency of crosstalk noise and delay on coupling parasitics (L12, C12) are analyzed.

The proposed MRTD method captures the behaviour of propagation delay and peak crosstalk noise on victim line against coupling parasitics, which is in close agreement with that of H simulation program with integrated circuit emphasis (HSPICE). The average error for the proposed model is less than 1 per cent with respect to HSPICE for the estimation of peak crosstalk noise voltage.

Simulations are performed using HSPICE and compared with those performed using the proposed MRTD method for global interconnect length with 130-nm technology, where the computations of the proposed model are carried out using Matlab.

The MRTD method with its unique features is tailored for modelling interconnects. To build further credence to this and its profound existence in the latest state-of-art works, simulations of crosstalk noise and propagation delay, for coupled Cu interconnect lines, using MRTD and finite-difference time-domain (FDTD) are executed. The results illustrated the dominance of MRTD method over FDTD in terms of accuracy.

An improved structure for adiabatic pseudo‐domino logic (APDL) family is presented in this paper. The modified dual‐rail improved APDL (MDIAPDL) exhibits lower power dissipation than the conventional static CMOS as shown in HSpice simulations. Comprehensive circuit simulations show that the MDIAPDL 4 bit shift register can recover over 95 per cent of the energy dissipated in conventional static CMOS 4 bit shift register.

The paper aims to present a simple rail‐to‐rail CMOS voltage follower.

The circuit is developed based on a complementary source follower with a common‐source output stage. The circuit is designed using a 0.13 μm CMOS technology, and operates under the supply voltage of 1.5 V. HSPICE is used to verify the circuit performance.

The simulations show output voltage swing of ±0.6 V (300 Ω load) with the total harmonic distortion of 0.55 per cent at the operating frequency of 3 MHz. The bandwidth and power dissipation are 657 MHz and 405 μW, respectively.

A simple rail‐to‐rail CMOS voltage follower is presented.

The performance of the conventional 6T SRAM cell can be improved by using GNRFET devices with multi-threshold technology. The proposed cell shows the strong capability to operate at the minimum supply voltage of 325 mV, whereas the conventional Si-CMOS 6 T SRAM unable to operate below 725 mV, which result in an acceptable failure rate.The advance of Si-CMOS (complementary metal-oxide-semiconductor) based 6 T SRAM cell faces inherent limitation with aggressive downscaling. Hence, there is a need to propose alternatives for the conventional cells.

This study aims to improve the performance of the conventional 6T SRAM cell using dual threshold technology, device sizing, optimization of supply voltage under process variation with GNRFET technology. Further performance can be enhanced by resolving half-select issue.

The GNRFET-based 6T SRAM cell demonstrates that it is capable of continued improve the performance under the process, voltage, and temperature (PVT) variations significantly better than its CMOS counterpart.

Nano-material fabrication technology of GNRFETs is in the early stage; hence, the different transistor models can be used to evaluate the parameters of future GNRFETs circuit.

GNRFET devices are suitable for implementing low power and high density SRAM cell.

The conventional Si-CMOS 6 T SRAM cell is a core component and used as the mass storage element in cache memory in computer system organization, mobile phone and other data storage devices.

This paper presents a new approach to implement an alternative design of GNRFET -based 6T SRAM cell with doped reservoirs that also supports process variation. In addition, multi-threshold technology optimizes the performance of the proposed cell. The proposed design provides a means to analyze delay and power of GNRFET-based SRAM under process variation with considering edge roughness, and offers design and fabrication insights for cell in the future.

This paper is an unprecedented effort to resolve the performance issue of very large scale integrated circuits (VLSI) interconnects encountered because of the scaling of device dimensions. Repeater interpolation technique is an effective approach for enhancing speed of interconnect network. Proposed buffers as repeater are modeled by using dual chirality multi-V_t technology to reduce delay besides mitigating average power consumption. Interconnects modeled with carbon nanotube (CNT) technology are compared with copper interconnect for various lengths. Buffer circuits are designed with both CNT and metal oxide semiconductor technology for comparison by using various combination of (CMOSFET repeater-Cu interconnect) and (CNTFET repeater-CNT interconnect). Compared to conventional buffer, ProposedBuffer1 saves dynamic power by 84.86%, leakage power by 88% and offers reduction in delay by 72%. ProposedBuffer2 brings about dynamic power saving of 99.94%, leakage power saving of 93%, but causes delay penalty. Simulation using Stanford SPICE model for CNT and silicon-field effective transistor berkeley short-channel IGFET Model4 (BSIM4) predictive technology model (PTM) for MOS is done in H simulation program with integrated circuit emphasis for 32 nm.

Usually, the dynamic power consumption dominates the total power, while the leakage power has a negligible effect. But with the scaling of device technology, leakage power has become one of the important factors of consideration in low power design techniques. Various strategies are explored to suppress the leakage power in standby mode. The adoption of a multi-threshold design strategy is an effective approach to improve the performance of buffer circuits without compromising on the delay and area overhead. Unlike MOS technology, to implement multi-V_t transistors in case of CNT technology is quite easy. It can be achieved by varying diameter of carbon nanotubes using chirality control.

An unprecedented approach is taken for optimizing the delay and power dissipation and hence drastically reducing energy consumption by keeping proper harmony between wire technology and repeater-buffer technology. This paper proposes two novel ultra-low power buffers (PB1 and PB2) as repeaters for high-speed interconnect applications in portable devices. PB1 buffer implemented with high-speed CML technique nested with multi-threshold (V_t) technology sleep transistor so as to improve the speed along with a reduction in standby power consumption. PB2 is judicially implemented by inserting separable sized, dual chirality P type carbon nanotube field effective transistors. The HSpice simulation results justify the correctness of schemes.

Result analysis points out that compared to conventional Cu interconnect, the CNT interconnects paired with Proposed CNTFET buffer designs are more energy efficient. PB1 saves dynamic power by 84.86%, reduces propagation delay by 72% and leakage power consumption by 88%. PB2 brings about dynamic power saving of 99.4%, leakage power saving of 93%, with improvement in speed by 52%. This is mainly because of the fact that CNT interconnect offers low resistance and CNTFET drivers have high mobility and ballistic mode of operation.

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.

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.

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.

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.

This paper aims to present an inexact 4:2 compressor cell using carbon nanotube filed effect transistors (CNFETs).

To design this cell, the capacitive threshold logic (CTL) has been used.

To evaluate the proposed cell, comprehensive simulations are carried out at two levels of the circuit and image processing. At the circuit level, the HSPICE software has been used and the power consumption, delay, and power-delay product are calculated. Also, the power-delaytransistor count product (PDAP) is used to make a compromise between all metrics. On the other hand, the Monte Carlo analysis has been used to scrutinize the robustness of the proposed cell against the variations in the manufacturing process. The results of simulations at this level of abstraction indicate the superiority of the proposed cell to other circuits. At the application level, the MATLAB software is also used to evaluate the peak signal-to-noise ratio (PSNR) figure of merit. At this level, the two primary images are multiplied by a multiplier circuit consisting of 4:2 compressors. The results of this simulation also show the superiority of the proposed cell to others.

This cell significantly reduces the number of transistors and only consists of NOT gates.

This paper aims to propose a new sleep signal controlled footless domino circuit for reducing the subthreshold and gate oxide leakage currents.

In the proposed circuit, a P channel MOSFET (PMOS) sleep switch transistor is inserted between the power supply and the output node. The sleep transistor, the source of the pull-down network, and the source of the N channel MOSFET (NMOS) transistor of the output inverter are controlled by this additional sleep signal to place the footless domino circuit in a low leakage state.

The authors simulate the proposed circuit by using HSPICE in 45-nm CMOS technology for OR and AND logic gates such as OR2, OR4, OR8, AND2 and AND4 at 25°C and 110°C. The proposed circuit reduces leakage power consumption as compared to the existing circuits.

The proposed circuit significantly reduces the total leakage power consumption up to 99.41 and 99.51 per cent as compared to the standard dual-threshold voltage footless domino circuits at 25°C and 110°C, respectively, and up to 93.79 and 97.98 per cent as compared to the sleep control techniques at 25°C and 110°C, respectively. Similarly, the proposed circuit reduces the active power consumption up to 26.76 and 86.25 per cent as compared to the standard dual-threshold voltage and sleep control techniques footless domino circuits at 25°C and 110°C, respectively.

The purpose of this paper is to investigate a more robust ring oscillator. Less sensitivity to power supply variations is a target. This is important since low-quality ring oscillators could be exploited in numerous systems to reduce die costs.

The method in this work is large signal analysis. Delay time as the large signal parameter is calculated symbolically to explore dependency on a power supply voltage. Then simulations are performed to make a comparison. In this work, mathematical justifications are verified via HSPICE circuit simulator outputs, while 0.18 µm TSMC CMOS technology is exploited.

At least two combined configurations are presented with higher robustness. These circuits are more appropriate in noisy conditions. Both theoretical calculations and simulation results verify less sensitive oscillation against supply voltage ripples and temperature variations.

Introducing a band-switched inverter in combined configurations is contribution. In this way, three structures are presented which both show higher stability in oscillation frequency. The band switched delay time calculations are quite new and also the validity of the symbolical delay time approach is verified by circuit simulations.