scholarly journals Digitally Controlled Oscillator with High Timing Resolution and Low Complexity for Clock Generation

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1377
Author(s):  
Duo Sheng ◽  
Wei-Yen Chen ◽  
Hao-Ting Huang ◽  
Li Tai

This paper presents a digitally controlled oscillator (DCO) with a low-complexity circuit structure that combines multiple delay circuits to achieve a high timing resolution and wide output frequency range simultaneously while also significantly reducing the overall power consumption. A 0.18 µm complementary metal–oxide–semiconductor standard process was used for the design, and measurements showed that the chip had a minimum controllable timing resolution of 4.81 ps and power consumption of 142 µW with an output signal of 364 MHz. When compared with other designs using advanced processes, the proposed DCO demonstrated the best power-to-frequency ratio. Therefore, it can output a signal at the required frequency more efficiently in terms of power consumption. Additionally, because the proposed DCO uses digital logic gates only, a cell-based design flow can be implemented. Hence, the proposed DCO is not only easy to implement in different processes but also easy to integrate with other digital circuits.

Electronics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 804
Author(s):  
Gibeom Shin ◽  
Kyunghwan Kim ◽  
Kangseop Lee ◽  
Hyun-Hak Jeong ◽  
Ho-Jin Song

This paper presents a variable-gain amplifier (VGA) in the 68–78 GHz range. To reduce DC power consumption, the drain voltage was set to 0.5 V with competitive performance in the gain and the noise figure. High-Q shunt capacitors were employed at the gate terminal of the core transistors to move input matching points for easy matching with a compact transformer. The four stages amplifier fabricated in 40-nm bulk complementary metal oxide semiconductor (CMOS) showed a peak gain of 24.5 dB at 71.3 GHz and 3‑dB bandwidth of more than 10 GHz in 68–78 GHz range with approximately 4.8-mW power consumption per stage. Gate-bias control of the second stage in which feedback capacitances were neutralized with cross-coupled capacitors allowed us to vary the gain by around 21 dB in the operating frequency band. The noise figure was estimated to be better than 5.9 dB in the operating frequency band from the full electromagnetic (EM) simulation.


2018 ◽  
Vol 7 (2.7) ◽  
pp. 647
Author(s):  
J Lakshmi Prasanna ◽  
V Sahiti ◽  
E Raghuveera ◽  
M Ravi Kumar

A 128-Bit Digital Comparator is designed with Digital Complementary Metal Oxide Semiconductor (CMOS) logic, with the use of Parallel Prefix Tree Structure [1] technique. The comparison is performed on Most Significant Bit (MSB) to the Least Significant Bit (LSB). The comparison for the lower order bits carried out only when the MSBs are equal. This technique results in Optimized Power consumption and improved speed of operation. To make the circuit regular, the design is made using only CMOS logic gates. Transmission gates were used in the existing design and are replaced with the simple AND gates. This 128-Bit comparator is designed using Cadence TSMC 0.18µm technology and optimized the Power dissipation to 0.28mW and with a Delay of 0.87μs. 


Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1617
Author(s):  
Ioannis Intzes ◽  
Hongying Meng ◽  
John Cosmas

Wireless Capsule Endoscopy is a state-of-the-art technology for medical diagnoses of gastrointestinal diseases. The amount of data produced by an endoscopic capsule camera is huge. These vast amounts of data are not practical to be saved internally due to power consumption and the available size. So, this data must be transmitted wirelessly outside the human body for further processing. The data should be compressed and transmitted efficiently in the domain of power consumption. In this paper, a new approach in the design and implementation of a low complexity, multiplier-less compression algorithm is proposed. Statistical analysis of capsule endoscopy images improved the performance of traditional lossless techniques, like Huffman coding and DPCM coding. Furthermore the Huffman implementation based on simple logic gates and without the use of memory tables increases more the speed and reduce the power consumption of the proposed system. Further analysis and comparison with existing state-of-the-art methods proved that the proposed method has better performance.


Electronics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 542 ◽  
Author(s):  
Haifeng Zhang ◽  
Zhaowei Zhang ◽  
Mingyu Gao ◽  
Li Luo ◽  
Shukai Duan ◽  
...  

A memristor is a nanoscale electronic element that displays a threshold property, non-volatility, and variable conductivity. Its composite circuits are promising for the implementation of intelligence computation, especially for logic operations. In this paper, a flexible logic circuit composed of a spintronic memristor and complementary metal-oxide-semiconductor (CMOS) switches is proposed for the implementation of the basic unbalanced ternary logic gates, including the NAND, NOR, AND, and OR gates. Meanwhile, due to the participation of the memristor and CMOS, the proposed circuit has advantages in terms of non-volatility and load capacity. Furthermore, the input and output of the proposed logic are both constant voltages without signal degradation. All these three merits make the proposed circuit capable of realizing the cascaded logic functions. In order to demonstrate the validity and effectiveness of the entire work, series circuit simulations were carried out. The experimental results indicated that the proposed logic circuit has the potential to realize almost all basic ternary logic gates, and even some more complicated cascaded logic functions with a compact circuit construction, high efficiency, and good robustness.


2014 ◽  
Vol 67 (1) ◽  
Author(s):  
Wong How Hwan ◽  
Vinny Lam Siu Fan ◽  
Yusmeeraz Yusof

The purpose of this research is to design a low power integrated complementary metal oxide semiconductor (CMOS) detection circuit for charge-modulated field-effect transistor (CMFET) and it is used for the detection of deoxyribonucleic acid (DNA) hybridization. With the available CMOS technology, it allows the realization of complete systems which integrate the sensing units and transducing elements in the same device. Point-of-care (POC) testing device is a device that allows anyone to operate anywhere and obtain immediate results. One of the important features of POC device is low power consumption because it is normally battery-operated. The power consumption of the proposed integrated CMOS detection circuit requires only 14.87 mW. The detection circuit will amplify the electrical signal that comes from the CMFET to a specified level in order to improve the recording characteristics of the biosensor. Self-cascode topology was used in the drain follower circuit in order to reduce the channel length modulation effect. The proposed detection circuit was designed with 0.18µm Silterra CMOS fabrication process and simulated under Cadence Simulation Tool. 


Electronics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1100
Author(s):  
Deeksha Verma ◽  
Khuram Shehzad ◽  
Danial Khan ◽  
Sung Jin Kim ◽  
Young Gun Pu ◽  
...  

A design of low-power 10-bit 1 MS/s asynchronous successive approximation register analog-to-digital converter (SAR ADC) is presented in this paper. To improve the linearity of the digital-to-analog converter (DAC) and energy efficiency, a common mode-based monotonic charge recovery (CMMC) switching technique is proposed. The proposed switching technique consumes only 63.75 CVREF2 switching energy, which is far less as compared to the conventional switching technique without dividing or adding additional switches. In addition, bootstrap switching is implemented to ensure enhanced linearity. To reduce the power consumption from the comparator, a dynamic latch comparator with a self-comparator clock generation circuit is implemented. The proposed prototype of the SAR ADC is implemented in a 55 nm CMOS (complementary metal-oxide-semiconductor) process. The proposed architecture achieves a figure of merit (FOM) of 17.4 fJ/conversion, signal-to-noise distortion ratio (SNDR) of 60.39 dB, and an effective number of bits (ENOB) of 9.74 bits with a sampling rate of 1 MS/s at measurement levels. The implemented SAR ADC consumes 14.8 µW power at 1 V power supply.


Circuit World ◽  
2019 ◽  
Vol 45 (4) ◽  
pp. 300-310
Author(s):  
Piyush Tankwal ◽  
Vikas Nehra ◽  
Sanjay Prajapati ◽  
Brajesh Kumar Kaushik

Purpose The purpose of this paper is to analyze and compare the characteristics of hybrid conventional complementary metal oxide semiconductor/magnetic tunnel junction (CMOS/MTJ) logic gates based on spin transfer torque (STT) and differential spin Hall effect (DSHE) magnetic random access memory (MRAM). Design/methodology/approach Spintronics technology can be used as an alternative to CMOS technology as it is having comparatively low power dissipation, non-volatility, high density and high endurance. MTJ is the basic spin based device that stores data in form of electron spin instead of charge. Two mechanisms, namely, STT and SHE, are used to switch the magnetization of MTJ. Findings It is observed that the power consumption in DSHE based logic gates is 95.6% less than the STT based gates. DSHE-based write circuit consumes only 5.28 fJ energy per bit. Originality/value This paper describes how the DSHE-MRAM is more effective for implementing logic circuits in comparison to STT-MRAM.


2015 ◽  
Vol 24 (03n04) ◽  
pp. 1550008 ◽  
Author(s):  
Bander Saman ◽  
P. Mirdha ◽  
M. Lingalugari ◽  
P. Gogna ◽  
F. C. Jain ◽  
...  

This paper presents the design and modeling of logic gates using two channel spatial wavefunction switched field-effect transistors (SWSFETs) it is also known as a twin-drain MOSFET. In SWSFETs, the channel between source and drain has two or more quantum wells (QWs) layers separated by a high band gap material between them. The gate voltage controls the charge carrier concentration in the two quantum wells layers and it causes the switching of charge carriers from one channel to other channel of the device. The first part of this paper shows the characteristics of n-channel SWSFET model, the second part provides the circuit topology for the SWSFET inverter and universal gates- NAND, AND, NOR,OR, XOR and XOR. The proposed model is based on integration between Berkeley Short-channel IGFET Model (BSIM) and Analog Behavioral Model (ABM), the model is suitable to investigate the gates configuration and transient analysis at circuit level. The results show that all basic two-input logic gates can be implanted by using n-channel SWSFET only, It covers less area compared with CMOS (Complementary metal–oxide–semiconductor) gates. The NAND-NOR can be performed by three SWSFET, moreover the exclusive-NOR “XNOR” can be done by four SWSFET transistors also AND, OR, XOR gates require two additional SWSFET for inverting.


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