Pipeline of Successive Approximation Converters with Optimum Power Merit Factor

In this paper, we present a low power 12 bit 5 MSPS, successive approximation converter architecture using pipeline technique. The converter consumes 4 mW at the Nyquist rate input with 1.8 V power supply. By combination of pipeline and successive architecture, the entire circuit, simulated at the transistor level in a 0.18 μ CMOS process, achieves a FoM (Figure of Merit) of 0.19 pJ/conversion. Jinghua Li was born in 1973. He received the MSEE and BSEE Degree from College of Electronics and information, Shanghai Jiaotong University and Harbin Engineering University in 1997 and 1994 respectively. He is currently pursuing Ph.D degree in Department of Electrical Engineering, Texas A&M University, College Station, TX, USA. In 1997, he joined Bell Laboratory (China), Lucent Technologies as a member of technical staff. He worked on single-chip HDTV decoder IC and Sonet/SDH SoC for various projects in Murray Hill, NJ, USA and Shanghai China. He also finished projects on hardware implementation of Video conference/Phone based on H.263 standard as his master thesis. Since 2000, he has been a research assistant in Analog Mixed Signal center, TAMU. Most currently his research interests are focused on low power analog to digital conversion IC design, CMOS implementation of 10 G/2.5 G clock data recovery IC for high speed serial communications. Franco Maloberti received the Laurea Degree in Physics (Summa cum Laude) from the University of Parma, Parma Italy, in 1968 and the Dr. Honoris Causa degree in electronics from the Instituto Nacional de Astrofisica, Optica y Electronica (Inaoe), Puebla, Mexico in 1996. In 1993 he was a Visiting Professor at ETH-PEL, Zurich. He was Professor of Microelectronics and Head of the Micro Integrated Systems Group University of Pavia, Pavia, Italy and the TI/J.Kilby Analog Engineering Chair Professor at the Texas A&M University. He is currently the Distinguished Microelectronic Chair Professor at University of Texas at Dallas and part-time Professor at the University of Pavia, Italy. His professional expertise is in the design, analysis and characterization of integrated circuits and analogue digital applications, mainly in the areas of switched capacitor circuits, data converters, interfaces for telecommunication and sensor systems, and CAD for analogue and mixed A-D design. He has written more than 250 published papers, three books and holds 15 patents. He was in 1992 recipient of the XII Pedriali Prize for his technical and scientific contributions to national industrial production. He was co-recipient of the 1996 Institute of Electrical Engineers (U.K.) Fleming Premium for the paper “CMOS Triode Transistor Transconductor for high-frequency continuous time filters.” He has been responsible at both technical and management levels for many research programs including ten ESPRIT projects and has served the European Commission as ESPRIT Projects' Evaluator, Reviewer and as European Union expert in many European Initiatives. He served the Academy of Finland on the assessment of electronic research in Academic institutions and on the research programs' evaluations. Dr. Maloberti was Vice-President, Region 8, of the IEEE Circuit and Systems Society from 1995 to 1997 and an Associate Editor of IEEE-Transaction on Circuit and System-II. He received the 1999 IEEE CAS Society Meritorious Service Award, the 2000 CAS Society Golden Jubilee Medal, and the IEEE Millenium Medal. He is the President of the IEEE Sensor Council and member of the Board of Governors of the IEEE CAS Society. He is a member of the Italian Electrothecnical and Electronic Society (AEI), the Editorial Board of Analog Integrated Circuits and Signal Processing, and Fellow of IEEE.     

Optimized reduction of spur tones in fractional frequency synthesizers

In this article the contribution of the digital \Upsigma\Updelta\Upsigma\Updelta modulator in fractional frequency synthesizers is explored. Due to the circuit’s non linear behavior, the spur tones generated by the digital \Upsigma\Updelta\Upsigma\Updelta modulation degrade the synthesizer’s phase noise even in regions where the charge pump noise is dominant. A new method to dither digital MASH \Upsigma\Updelta\Upsigma\Updelta modulators for fractional frequency synthesizers is proposed. The method barely increases the circuit complexity and has the same performance as more cumbersome architectures. Also, a new design consideration to linearize the voltage control oscillator is proposed. Experimental results are obtained in an on-chip fractional synthesizer manufactured in CMOS technology.     

Near‐Infrared (NIR) Organic Light‐Emitting Diodes (OLEDs): Challenges and Opportunities

The rapid development of the science and technology of organic semiconductors has already led to mass application of organic light‐emitting diodes (OLEDs) in television monitors of outstanding quality as well as in a large variety of smaller displays found in smartphones, tablets, and other gadgets, while introduction of the technology to the illumination sector is imminent. Notably, the requirements of all such applications for emission in the visible range of the electromagnetic spectrum are well tuned to the optical and electronic properties of typical organic semiconductors, thereby representing relatively “low‐hanging fruits,” in terms of material development and exploitation. However, the question arises as to whether developing materials suited for efficient near‐infrared (NIR, 700–1000 nm) emission is possible, and, crucially, desirable to enable new classes of applications spanning from through‐space, short‐range communications to biomedical sensors, night vision, and more generally security applications to name but a few. Here, the major fundamental hurdles to be overcome to achieve efficient NIR emission from organic π‐conjugated systems are discussed, recent progress is reviewed, and an outlook for further development of both materials and applications is provided.     

Thermal-lens and photo-acoustic methods for the determination of SiC thermal properties

In this paper we report the use of photothermal techniques such as Thermal lens (TL) spectrometry, Photoacoustic and heat capacity, ρc_p, to determine the thermo-optical parameters, such as thermal conductivity (K), thermal diffusivity (D), specific heat (c_p) and the optical path dependence with temperature (ds/dT), of an undoped polycrystalline 3C-SiC. To our knowledge, this is the first time that Thermal lens technique is used for wide band-gap systems. Results obtained for the polycrystalline sample with TL technique indicates that ds/dT is negative at room temperature. Moreover, the obtained values of thermal diffusivity and thermal conductivity are in good agreement with that found in the literature, indicating that the phototermal techniques can be used to obtain the referred parameters in circumstances where other techniques cannot be used, for example, in harsh environments.     

Synthetic Crystals of Silver with Carbon: 3D Epitaxy of Carbon Nanostructures in the Silver Lattice

Only minimum amounts of carbon can be incorporated into silver, gold, and copper in a thermodynamically stable form. Here, the structure of stable silver carbon alloys is described, which are produced by thermoelectrically charging molten silver with carbon ions. Transmission electron microscopy and Raman scattering are combined to establish that large amount of carbon is accommodated in the form of epitaxial graphene‐like sheets. The carbon bonds covalently to the silver matrix as predicted from density functional theory (DFT) calculations with bond energies in the range 1.1–2.2 eV per atom or vacancy. Graphitic‐like sheets embedded in the crystal lattice of silver form 3D epitaxial structures with the host metal with a strain of ≈13% compared to equilibrium graphene. The carbon nanostructures persist upon remelting and resolidification. A DFT‐based analysis of the phonon density of states confirms the presence of intense vibration modes related to the Ag? C bonds observed in the Raman spectra of the alloy. The solid silver–high carbon alloy, termed “Ag‐covetic,” displays room temperature electrical conductivity of 5.62 × 10⁷ S m^?1 even for carbon concentrations of up to ≈6 wt% (36 at%). This process of incorporation of carbon presents a new paradigm for electrocharging assisted bulk processing.     

Phase transmittance RBF neural networks

Presented is a new complex valued radial basis function (RBF) neural network with phase transmittance between the input nodes and output, which makes it suitable for channel equalisation on quadrature digital modulation systems.