A 0.1 MHz to 200 MHz high-voltage CMOS transceiver for portable NMR systems with a maximum output current of 2.0 App

We proposed a new method for designing the CMOS differential log-companding amplifier which achieves significant improvements in linearity, common-mode rejection ratio (CMRR), and output range. With the new nonlinear function used in the log-companding technology, this proposed amplifier has a very small total harmonic distortion (THD) and simultaneously a wide output current range. Furthermore, a differential structure with conventionally symmetrical configuration has been adopted in this novel method in order to obtain a high CMRR. Because all transistors in this amplifier operate in the weak inversion, the supply voltage and the total power consumption are significantly reduced. The novel log-companding amplifier was designed using a 0.18 μm CMOS technology. Improvements in THD, output current range, noise, and CMRR are verified using simulation data. The proposed amplifier operates from a 0.8 V supply voltage, shows a 6.3 μA maximum output current range, and has a 6 μW power consumption. The THD is less than 0.03%, the CMRR of this circuit is 74 dB, and the input referred current noise density is166.1 fA/Hz. This new method is suitable for biomedical applications such as electrocardiogram (ECG) signal acquisition.

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AlGaN/GaN High Electron Mobility Transistors on Semi-Insulating Ammono-GaN Substrates with Regrown Ohmic Contacts

Micromachines ◽

10.3390/mi9110546 ◽

2018 ◽

Vol 9 (11) ◽

pp. 546 ◽

Cited By ~ 10

Author(s):

Wojciech Wojtasiak ◽

Marcin Góralczyk ◽

Daniel Gryglewski ◽

Marcin Zając ◽

Robert Kucharski ◽

...

Keyword(s):

Electron Mobility ◽

Ohmic Contacts ◽

High Electron Mobility Transistors ◽

High Electron Mobility Transistor ◽

Maximum Output ◽

High Electron ◽

Output Current ◽

High Electron Mobility ◽

Electron Mobility Transistors ◽

Access Resistance

AlGaN/GaN high electron mobility transistors on semi-insulating bulk ammonothermal GaN have been investigated. By application of regrown ohmic contacts, the problem with obtaining low resistance ohmic contacts to low-dislocation high electron mobility transistor (HEMT) structures was solved. The maximum output current was about 1 A/mm and contact resistances was in the range of 0.3–0.6 Ω ·mm. Good microwave performance was obtained due to the absence of parasitic elements such as high access resistance.

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Optoelectronic CMOS Transistors: Performance Advantages for Sub-7nm ULSI, RF ASIC, Memories, and Power MOSFETs

MRS Advances ◽

10.1557/adv.2019.211 ◽

2019 ◽

Vol 4 (48) ◽

pp. 2585-2591

Author(s):

James N. Pan

Keyword(s):

Low Power ◽

High Voltage ◽

Series Resistance ◽

Access Time ◽

Cmos Process ◽

Output Current ◽

Process Flow ◽

Power Mosfets ◽

Cmos Transistors ◽

Low Power Cmos

AbstractSubstantial increase of output current, and Ion / Ioff ratio for sub-7nm low power CMOS transistors, can be accomplished using a novel optoelectronic technology, which is 100% compatible with existing CMOS process flow. For RF or mixed signal ASICs, adding photonic components may improve the cut-off frequency, and reduce series resistance. Products that utilize power regulating devices, such as power MOSFETs, will benefit from the optoelectronic configuration to achieve much lower Rdson and high voltage at the same time. For semiconductor memories, such as DRAM or FLASH, the photonic technique may reduce the ERASE / WRITE / access time and improve the reliability.

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Fast True RMS Algorithm Using in the High-Voltage General Inverter

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.614-615.1244 ◽

2012 ◽

Vol 614-615 ◽

pp. 1244-1249

Author(s):

Zhi Fei Yu ◽

Bing Li ◽

Wei Wang ◽

Shi Bao Qian

Keyword(s):

Control System ◽

Real Time ◽

High Voltage ◽

Computation Time ◽

Current Signal ◽

Output Current ◽

Safe Operation ◽

Harmonic Current ◽

Overload Protection ◽

Mean Filter

The high-voltage general inverter which has the advantage of the structure， has become the key equipment to saving energy in recent years. The inverter output current is the key variable of overload protection, over current protection and V/F control compensation, so the real-time accurate measurement of its RMS is extremely important. In this paper, the output current signals preprocess by hardware filter firstly, and then find the RMS of the current signal in the period of the waveform. Meanwhile, this algorithm belong to true RMS algorithm category, which suitable for testing harmonic current signal, and can avoid mean filter to reduce the computation time. By using this algorithm, the inverter control system provides accurate reference for overload protection reduces the systematic disoperation rate and sets the more accurate security allowance to ensure the safe operation of equipment.

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Acoustic wave-driven oxidized liquid metal-based energy harvester

The European Physical Journal Applied Physics ◽

10.1051/epjap/2018180011 ◽

2018 ◽

Vol 81 (2) ◽

pp. 20902 ◽

Cited By ~ 4

Author(s):

Jinpyo Jeon ◽

Sang Kug Chung ◽

Jeong-Bong Lee ◽

Seok Joo Doo ◽

Daeyoung Kim

Keyword(s):

Liquid Metal ◽

Acoustic Wave ◽

Double Layer ◽

Electrical Double Layer ◽

Energy Harvester ◽

Metal Droplet ◽

Acoustic Energy ◽

Maximum Output ◽

Output Current ◽

Liquid Metal Droplet

We report an oxidized liquid metal droplet-based energy harvester that converts acoustic energy into electrical energy by modulating an electrical double layer that originates from the deformation of the oxidized liquid metal droplet. Gallium-based liquid metal alloy has been developed for various applications owing to the outstanding material properties, such as its high electrical conductivity (metallic property) and unlimited deformability (liquid property). In this study, we demonstrated energy harvesting using an electrical double layer between the acoustic wave-modulated liquid metal droplet and two electrodes. The proposed energy harvester consisted of top and bottom electrodes covered with the dielectric layer and a Gallium-based liquid metal droplet placed between the electrodes. When we applied an external bias voltage and acoustic wave to the proposed device, the contact area between the liquid metal droplet and the electrodes changed, leading to the variation of the capacitance in the electrical double layer and the generation of electrical output current. Using the proposed energy harvester, the maximum output current of 41.2 nA was generated with an applied acoustic wave of 30 Hz. In addition, we studied the relationships between the maximum output current and a variety of factors, such as the size of the liquid metal droplet, the thickness of the hydrophobic layer, and the distance between the top and bottom electrode plates.

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