Design of a Sub-mW 960-MHz UWB CMOS LNA

This paper presents a sub-mW ultra-wideband (UWB) fully differential CMOS low-noise amplifier (LNA) operating below 960 MHz for sensor network applications. By utilizing both nMOS and pMOS transistors to boost the transconductance, coupling the input signals to the back-gates of the transistors, and combining the common-gate and shunt-feedback topologies, the LNA achieves 13 dB of power gain, a 3.6 dB minimum noise figure, and -10 dBm of IIP3 with only 0.72 mW of power consumption from a 1.2 V supply     

BSIM模型的研究和最近进展

CMOS集成电路技术的进一步发展和不断出现的新技术应用要求我们持续地改进和增强VLSI电路设计和模拟的集约模型.基于此,美国Berkeley加州大学的BSIM团队对国际工业标准芯片仿真物理模型BSIM进行了一系列的研究和发展工作.本文分析和介绍了最近几年来本人参与其中的BSIM工程的研究和进展情况,包括BSIM5的研究,BSIM4的增强和BSIMSOI的发展.BSIM5是为满足RF和高速CMOS电路模拟要求而发展的新一代物理基础的BSIM模型,具有对称、连续和参数少的特点.BSIM4是一个成熟的工业标准仿真模型,在衬底电阻网络、隧穿电流、饱和电流原理和应力模型等方面有一系列的功能增强以支持技术进步的需求.BSIMSOI已经发展成可应用于SOI-PD和SOI-FD技术的普适模型,通过有效体电势△Vbi的改变进行器件工作模式的选择,可以帮助电路设计者实现PD和FD共存的设计趋势.     

Comparisons between experiment and theory for dropwise condensation of mercury

It is shown that convenient approximations, used in the theory of dropwise condensation to evaluate the integral giving the heat flux, lead to significant errors for the case of mercury. When these approximations are not adopted, and the integral is found numerically, agreement between theory and experiment is markedly improved.     

Thermosensitive biotinylated hydroxypropyl cellulose-based polymer micelles as a nano-carrier for cancer-targeted drug delivery

In this article, we report the synthesis of a novel amphiphilic hydroxypropyl cellulose-based polymer (HPC-PEG-Chol) that contained poly (ethylene glycol) and cholesterol-containing moieties with specific degrees of substitution. The resulting polymer was subsequently converted to a biotin conjugate (HPC-PEG-Chol-biotin), to develop a new potential cancer-targeted drug delivery system. The biotin conjugate was used to prepare micelles via the dialysis method. The polymeric micelles in aqueous solution presented a lower critical solution temperature (LCST) of 39.8 ^oC. The critical micelle concentration (CMC) values of the polymeric micelles at 25 and 45 °C were evaluated to be about 0.32 and 0. 25 g/L, respectively. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) analyses of the micelles revealed the spherical shapes of the micelles, with 84 nm mean diameters that increased with the increase of the temperature above LCST. The hydrophobic anticancer drug paclitaxel (PTX) was loaded in the micelles and the in vitro release behaviors of PTX were investigated at different temperatures. The release profile of PTX from the polymeric micelles revealed a thermosensitivity, since its release rate was higher at 41 °C than at 37 °C. Fluorescent microscopy analyses confirm that the PTX-loaded HPC-PEG-Chol-biotin is superior in cellular uptake, with very strong adsorption to both HeLa and MDA-MB-231 cancer cell lines. MTT assay in normal cells indicated that HPC-PEG-Chol-biotin micelles have great potential to be safely used in tumor-targeting chemotherapy.     

Effects of NO2 ? and NO3 ? Ions on Corrosion of AISI 4130 Steel in Ethylene Glycol?+?Water Electrolyte

The electrochemical behavior of steel alloy in ethylene glycol?Cwater mixture was investigated by electrochemical methods. The results obtained showed that corrosion rate was decreased with increasing ethylene glycol concentration. The effect of nitrite and nitrate as inhibitor was studied and higher inhibition efficiency was obtained for nitrite. It was found that surface passivation occurred in presence of inhibitor. The inhibiting effect of the nitrite was explained on the basis of the competitive adsorption between the inorganic anions and the aggressive Cl^? ions and the adsorption isotherm basically obeys the Flory?CHuggins adsorption isotherm. Thermodynamic parameters for inhibitor adsorption were determined and reveal that the adsorption process is spontaneous.     

A 1.8-GHz LC VCO with 1.3-GHz tuning range and digital amplitude calibration

A 1.8-GHz LC VCO designed in a 0.18-/spl mu/m CMOS process achieves a very wide tuning range of 73% and measured phase noise of -123.5 dBc/Hz at a 600-kHz offset from a 1.8-GHz carrier while drawing 3.2 mA from a 1.5-V supply. The impacts of wideband operation on start-up constraints and phase noise are discussed. Tuning range is analyzed in terms of fundamental dimensionless design parameters yielding useful design equations. An amplitude calibration technique is used to stabilize performance across the wide band of operation. This amplitude control scheme not only consumes negligible power and area without degrading the phase noise, but also proves to be instrumental in sustaining the VCO performance in the upper end of the frequency range.     

Embedding Mixed-Signal Design in Systems-on-Chip

With semiconductor technology feature size scaling below 100 nm, mixed-signal design faces some important challenges, caused among others by reduced supply voltages, process variation, and declining intrinsic device gains. Addressing these challenges requires innovative solutions, at the technology, circuit, architecture, and design-methodology level. We present some of these solutions, including a structured platform-based design methodology to enable a meaningful exploration of the broad design space and to classify potential solutions in terms of the relevant metrics.     

High-performance inductors using capillary based fluidic self-assembly

In this paper, a batch microfabrication process is presented for creating high aspect ratio, micron-sized helical and toroidal inductors with Q greater than or equal to 50 at multi-GHz frequencies. With a maximum processing temperature of only 220/spl deg/C, the inductors can be fabricated on top of standard CMOS wafers. This process can also be used to create "inductor chiplets", which are polymer-encapsulated inductors with the same form factor as an EIA (Electronics Industries Association) standard 0201 surface mount device. The chiplets can be assembled onto CMOS wafers using a fluidic microassembly technique. This technique allows for multiple electrical interconnects to the inductor chiplets. The 40-/spl mu/m gap between the substrate and assembled inductor increases the Q by a factor of /spl sim/3 compared to as-fabricated inductors. Assembled and as-fabricated inductors have been characterized on similar substrates and have maximum Q values of 50 and 15 with resonant frequencies of 10 GHz and 9 GHz, respectively. Performance of the assembled inductors is nearly comparable to that of inductors as fabricated and tested on quartz substrates.