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Shey-Shi Lu

Bio: Shey-Shi Lu is an academic researcher from National Taiwan University. The author has contributed to research in topics: CMOS & Noise figure. The author has an hindex of 30, co-authored 300 publications receiving 3431 citations. Previous affiliations of Shey-Shi Lu include National Chi Nan University & National Taiwan University of Science and Technology.


Papers
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Journal ArticleDOI
TL;DR: In this article, the design principles of CMOS low-noise amplifiers (LNAs) for simultaneous input impedance and noise matching by tailoring device size for R/sub opt/=50 /spl Omega/ are introduced.
Abstract: Design principles of CMOS low-noise amplifiers (LNAs) for simultaneous input impedance and noise matching by tailoring device size for R/sub opt/=50 /spl Omega/ are introduced. It is found that R/sub opt/ close to 50 /spl Omega/ can be obtained by using small devices (110 /spl mu/m) and small currents (5 mA). Based on the proposed approach, CMOS LNAs with on-chip input and output matching networks on thin (/spl sim/20 /spl mu/m) and normal (750 /spl mu/m) substrates are implemented. It is found that the noise figure (NF) (3.0 dB) of the CMOS LNA at 5.2 GHz with 10-mW power consumption on the normal (750 /spl mu/m) substrate can be reduced to 2.17 dB after the substrate is thinned down to /spl sim/20 /spl mu/m. The reduction of NF is attributed to the suppression of substrate loss of the on-chip inductors. The input return loss (S/sub 11/) is smaller than -22 dB across the entire band of interest (5.15-5.35 GHz). An input 1-dB compression point (P/sub 1 dB/) of -8.3 dBm and an input third-order intercept point of 0.8 dBm were also obtained for the LNA on the thin substrate.

156 citations

Journal ArticleDOI
TL;DR: In this paper, a wideband low-noise amplifier (LNA) based on the current-reused cascade configuration is proposed, which takes advantage of the resistive shunt-shunt feedback in conjunction with a parallel LC load to make the input network equivalent to two parallel RLC-branches.
Abstract: A wideband low-noise amplifier (LNA) based on the current-reused cascade configuration is proposed. The wideband input-impedance matching was achieved by taking advantage of the resistive shunt-shunt feedback in conjunction with a parallel LC load to make the input network equivalent to two parallel RLC-branches, i.e., a second-order wideband bandpass filter. Besides, both the inductive series- and shunt-peaking techniques are used for bandwidth extension. Theoretical analysis shows that both the frequency response of input matching and noise figure (NF) can be described by second-order functions with quality factors as parameters. The CMOS ultra-wideband LNA dissipates 10.34-mW power and achieves S 11 below -8.6 dB, S 22 below -10 dB, S 12 below -26 dB, flat S 21 of 12.26 ± 0.63 dB, and flat NF of 4.24 ± 0.5 dB over the 3.1-10.6-GHz band of interest. Besides, good phase linearity property (group-delay variation is only ±22 ps across the whole band) is also achieved. The analytical, simulated, and measured results agree well with one another.

147 citations

Journal ArticleDOI
TL;DR: In this paper, a wideband low-noise amplifier (LNA) based on the cascode configuration with resistive feedback is presented, which achieves S11 below -10 dB, S22 below - 10 dB, flat S21 of 9.6 ± 1.1 dB, and flat NF of 3.68 ± 0.72 dB over the 1.6-28 GHz band.
Abstract: This paper presents a wideband low-noise amplifier (LNA) based on the cascode configuration with resistive feedback. Wideband input-impedance matching was achieved using a shunt-shunt feedback resistor in conjunction with a preceding π -match network, while the wideband gain response was obtained using a post-cascode inductor (LP), which was inserted between the output of the cascoding transistor and the input of the shunt-shunt resistive feedback network to enhance the gain and suppress noise. Theoretical analysis shows that the frequency response of the power gain, as well as the noise figure (NF), can be described by second-order functions with quality factors or damping ratios as parameters. Implemented in 90-nm CMOS technology, the die area of this wideband LNA is only 0.139 mm2 including testing pads. It dissipates 21.6-mW power and achieves S11 below -10 dB, S22 below -10 dB, flat S21 of 9.6 ±1.1 dB, and flat NF of 3.68 ± 0.72 dB over the 1.6-28-GHz band. Besides, excellent input third-order inter-modulation point of +4 dBm is also achieved. The analytical, simulated, and measured results are mutually consistent.

114 citations

Journal ArticleDOI
TL;DR: A highly adaptive multi-sensor SoC comprising four on-chip sensors and a smart wireless acquisition system is first realized in standard CMOS process and Experimental results show that four physiological parameters can be simultaneously monitored using this chip.
Abstract: A highly adaptive multi-sensor SoC comprising four integrated on-chip sensors and a smart wireless acquisition system is realized in standard CMOS process for the first time. To intelligently process different types (C, R, I, and V) of sensor signals, a linear (R-square is 0.999) and reconfigurable sensor readout is proposed based on switched-capacitor circuit technology. In addition, a dual-input energy harvesting interface with conversion efficiency of 73% is also integrated to pick up light energy and RF power, which potentiates long-term use without battery replacement. The entire SoC occupies die area of 11.25 mm 2 and consumes only 942.9 μW. Experimental results show that four physiological parameters (temperature, glucose and protein concentration, and pH value) can be simultaneously monitored using this chip. This system can be seen as a universal sensor platform. Different types of sensors can be easily integrated into it for convenient use, which dramatically reduces time consuming of building a new sensor system.

104 citations

Journal ArticleDOI
TL;DR: In this article, a dual-feedback circuit methodology is proposed to explain the kink phenomenon of transistor scattering parameter S/sub 22/ in a Smith chart, which can predict the behavior of all transistors and calculate all S-parameters accurately.
Abstract: A novel theory based on dual-feedback circuit methodology is proposed to explain the kink phenomenon of transistor scattering parameter S/sub 22/. Our results show that the output impedance of all transistors intrinsically shows a series RC circuit at low frequencies and a parallel RC circuit at high frequencies. It is this inherent ambivalent characteristic of the output impedance that causes the appearance of kink phenomenon of S/sub 22/ in a Smith chart. It was found that an increase of transistor transconductance enhances the kink effect while an increase of drain-to-source (or collector-to-emitter) capacitance obscures it. This explains why it is much easier to see the kink phenomenon in bipolar transistors, especially heterojunction bipolar transistors, rather than in field-effect transistors (FETs). It also explains why the kink phenomenon is seen in larger size FETs and not in smaller size FETs. Our model not only can predict the behavior of S/sub 22/, but also calculate all S-parameters accurately. Experimental data of submicrometer gate Si MOSFETs and GaAs FETs are used to verify our theory. A simple method for extracting transistor equivalent-circuit parameters from measured S-parameters is also proposed based on our theory. Compared with traditional Z- or Y-parameter methods, our theory shows another advantage of giving deep insight into the physical meaning of S-parameters.

91 citations


Cited by
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01 Jan 2016
TL;DR: The design of analog cmos integrated circuits is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can download it instantly.
Abstract: Thank you for downloading design of analog cmos integrated circuits. Maybe you have knowledge that, people have look hundreds times for their chosen books like this design of analog cmos integrated circuits, but end up in malicious downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they juggled with some harmful virus inside their computer. design of analog cmos integrated circuits is available in our book collection an online access to it is set as public so you can download it instantly. Our digital library spans in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the design of analog cmos integrated circuits is universally compatible with any devices to read.

1,038 citations

Journal ArticleDOI
18 Jul 2011
TL;DR: An overview of the technological advances in millimeter-wave circuit components, antennas, and propagation that will soon allow 60-GHz transceivers to provide multigigabit per second (multi-Gb/s) wireless communication data transfers in the consumer marketplace is presented.
Abstract: This tutorial presents an overview of the technological advances in millimeter-wave (mm-wave) circuit components, antennas, and propagation that will soon allow 60-GHz transceivers to provide multigigabit per second (multi-Gb/s) wireless communication data transfers in the consumer marketplace. Our goal is to help engineers understand the convergence of communications, circuits, and antennas, as the emerging world of subterahertz and terahertz wireless communications will require understanding at the intersections of these areas. This paper covers trends and recent accomplishments in a wide range of circuits and systems topics that must be understood to create massively broadband wireless communication systems of the future. In this paper, we present some evolving applications of massively broadband wireless communications, and use tables and graphs to show research progress from the literature on various radio system components, including on-chip and in-package antennas, radio-frequency (RF) power amplifiers (PAs), low-noise amplifiers (LNAs), voltage-controlled oscillators (VCOs), mixers, and analog-to-digital converters (ADCs). We focus primarily on silicon-based technologies, as these provide the best means of implementing very low-cost, highly integrated 60-GHz mm-wave circuits. In addition, the paper illuminates characterization techniques that are required to competently design and fabricate mm-wave devices in silicon, and illustrates effects of the 60-GHz RF propagation channel for both in-building and outdoor use. The paper concludes with an overview of the standardization and commercialization efforts for 60-GHz multi-Gb/s devices, and presents a novel way to compare the data rate versus power efficiency for future broadband devices.

907 citations

01 Aug 2008
TL;DR: In this paper, a strain sensor was fabricated from a polymer nanocomposite with multiwalled carbon nanotube (MWNT) fillers, and the piezoresistivity of the sensor was investigated based on an improved three-dimensional (3D) statistical resistor network.
Abstract: A strain sensor has been fabricated from a polymer nanocomposite with multiwalled carbon nanotube (MWNT) fillers. The piezoresistivity of this nanocomposite strain sensor has been investigated based on an improved three-dimensional (3D) statistical resistor network model incorporating the tunneling effect between the neighboring carbon nanotubes (CNTs), and a fiber reorientation model. The numerical results agree very well with the experimental measurements. As compared with traditional strain gauges, much higher sensitivity can be obtained in the nanocomposite sensors when the volume fraction of CNT is close to the percolation threshold. For a small CNT volume fraction, weak nonlinear piezoresistivity is observed both experimentally and from numerical simulation. The tunneling effect is considered to be the principal mechanism of the sensor under small strains.

685 citations

Journal ArticleDOI
TL;DR: In this paper, the authors proposed a wideband ultra wideband (UWB) communication protocol with a low EIRP level (−41.3dBm/MHz) for unlicensed operation between 3.1 and 10.6 GHz.
Abstract: Before the emergence of ultra-wideband (UWB) radios, widely used wireless communications were based on sinusoidal carriers, and impulse technologies were employed only in specific applications (e.g. radar). In 2002, the Federal Communication Commission (FCC) allowed unlicensed operation between 3.1–10.6 GHz for UWB communication, using a wideband signal format with a low EIRP level (−41.3dBm/MHz). UWB communication systems then emerged as an alternative to narrowband systems and significant effort in this area has been invested at the regulatory, commercial, and research levels.

452 citations

Patent
08 Jun 2011
TL;DR: A system for designing a therapy or for treating a gastrointestinal disorder or a condition associated with excess weight in a subject comprising at least one electrode configured to be implanted within a body of the patient and placed at a vagus nerve is described in this article.
Abstract: A system for designing a therapy or for treating a gastrointestinal disorder or a condition associated with excess weight in a subject comprising at least one electrode configured to be implanted within a body of the patient and placed at a vagus nerve, the electrode also configured to apply therapy to the vagus nerve upon application of a therapy cycle to the electrode; an implantable neuroregulator for placement in the body of the patient beneath the skin layer, the implantable neuroregulator being configured to generate a therapy cycle, wherein the therapy cycle comprises an on time during which an electrical signal is delivered, the electrical signal comprising: a) a set of pulses applied at a first selected frequency of about 150-10,000 Hz, wherein each pulse of the set of pulses has a pulse width of at least 0.01 milliseconds and less than the period of the first selected frequency.

433 citations