Current source based standard-cell model for accurate timing analysis of combinational logic cells
Timing verification is an essential process in nanometer design. Therefore, static timing analysis (STA) is currently the main aspect of performance verification. Traditional STA is based on lookup tables with input slew and output load capacitance. It is becoming insufficient to accurately characterize many significant aspects of the conventional cell delays models, such as: the process variations, nonlinear waveforms, nonlinear loads, and multiple inputs switching (MIS). Therefore, the current trend in modern designs is to use current source based models (CSM), which model MOSFETs as a
Circuit Theory and Applications
A novel high throughput high resolution two-stage oscillator-based TDC
The modified single input Op-Amps memristor based oscillator
This paper introduces the modified single input Op-Amps memristor based oscillator. The oscillator is realized with ideal, LM741 and current feedback (AD844) Op-Amps where memristors replace resistors. The effect of memristor on the oscillation frequency and the oscillation condition that are totally independent is studied. This helped in studying the whole operation regime of the memristor. The effect of initial conditions on the circuit behavior is discussed. The dynamic poles of the oscillator after resistors replacement are illustrated. Sustained oscillation is obtained and simulated
Circuit Theory and Applications
Generalized hardware post-processing technique for chaos-based pseudorandom number generators
This paper presents a generalized post-processing technique for enhancing the pseudorandomness of digital chaotic oscillators through a nonlinear XOR-based operation with rotation and feedback. The technique allows full utilization of the chaotic output as pseudorandom number generators and improves throughput without a significant area penalty. Digital design of a third-order chaotic system with maximum function nonlinearity is presented with verified chaotic dynamics. The proposed post-processing technique eliminates statistical degradation in all output bits, thus maximizing throughput
Circuit Theory and Applications
A 2.5 μwatts two stage wake-up receiver for Wireless Sensor Networks
An ultra low power wake-up receiver for Wireless Sensor Network (WSN) applications is presented. The proposed wake-up receiver is composed of two stages. The first stage is a low-power low-sensitivity stage that acts as a 'sentinel' and continuously monitors the channel, while the second stage is a conventional low-power wake-up receiver. The 2.44GHz two-stage receiver has a sensitivity of -72dBm when the transmitted signal power is 0dBm. The power consumed during sleep mode is 2.5μWatts and 41μWatts in the wake-up receiver active mode with a 0.5V supply voltage. The power consumption is
Circuit Theory and Applications
A Novel Actuator Fault-tolerant Control Strategy of DFIG-based Wind Turbines Using Takagi-Sugeno Multiple Models
In this paper, a new combined fuzzy observer-based fault-tolerant tracking control scheme is proposed for a doubly fed induction generator (DFIG) based wind turbine (WT) subject to actuator faults. The main contribution consists of the proposal of a novel fault-tolerant fuzzy tracking controller combined with a nominal control law. The control objective is to ensure good state references tracking regardless of the actuator faults effects and simultaneous system state and faults estimation. This later requires the knowledge of the occurrence of actuator faults which are estimated from a Takagi
Circuit Theory and Applications
On the mathematical modeling of memcapacitor bridge synapses
Mem-element based synaptic bridge is very promising topic due to its learning capability where the synaptic bridge can be build using either memristors or memcapacitors. In this paper, the detailed mathematical analysis of memcapacitor bridge circuit is introduced. This mathematical analysis is build when a current input signal is applied to excite the bridge. Closed form expressions for the required pulse width; synaptic weight; and conditions for positive, negative and zero synaptic weight are derived. The obtained expressions are verified using SPICE simulations showing very good matching.
Circuit Theory and Applications
Spectral current-voltage analysis of kesterite solar cells
Current-voltage analysis using different optical band pass filters has been performed on Cu2ZnSnSe4 and Cu2ZnSn(S,Se) 4 thin-film solar cells. When using red or orange light (i.e. wavelengths above 600 nm), a distortion appears in the I-V curve of the Cu 2ZnSnSe4 solar cell, indicating an additional potential barrier to the current flow in the device for these conditions of illumination. This barrier is reduced when using a Cu2ZnSn(S,Se)4 absorber. Numerical simulations demonstrate that the barrier visible under red light could be explained by a positive conduction band offset at the front
Circuit Theory and Applications
Memristor-less current- and voltage-controlled meminductor emulators