A 12bit 300MHz Current-Steering CMOS D/A Converter

The proposed DAC consists of a unit current-cell matrix for 8MSBs and a binary-weighted array for 4LSBs,trading-off between the precision,speed,and size of the chip.In order to ensure the linearity of the DAC,a double Centro symmetric current matrix is designed by the Q2 random walk strategy.To achieve better dynamic performance,a latch is added in front of the current switch to change the input signal,such as its optimal cross-point and voltage level.For a 12bit resolution,the converter reaches an update rate of 300MHz.

A 10bit 2GHz CMOS D/A Converter for High-Speed System Applications

This paper presents a 2GS/s 10bit CMOS digital-to-analog converter （DAC） that consists of two unit current-cell matrixes for 6MSBs and 4LSBs, respectively, trading off between the precision and size of the chip. Current mode logic （CML） is used to ensure high speed,and a double centro-symmetric current matrix is designed by the Q^2 random walk strategy in order to ensure the linearity of the DAC. The DAC occupies 2.2mm × 2.2mm of die area and consumes 790mW with a single 3.3V power supply.

Some Tools to Model Ground or Supply Bounces Induced in and out of Heterogeneous Integrated Circuits

Electrical ground looks simple on a schematic; unfortunately, the actual performance of a circuit is dictated by its layout （and by its printed-circuit-board）. When the ground node moves, system performance suffers and the system radiates electromagnetic interferences. But the understanding of the physics of ground noise can provide an intuitive sense for reducing the problem. Ground bounce can produce transients with amplitudes of volts; most often changing magnetic flux is the cause; in this work, the authors use a Finite-Difference Time-Domain to begin to understand such phenomena. Additionally, predicting substrate cross-talks in mixed-signal circuits has become a critical issue to preserve signal integrity in future integrated systems. Phenomena that involve parasitic signal propagation into the substrate are discussed. A simple methodology to predict the substrate cross-talk and some associated tools are presented. Finally, the authors indicate a stochastic method which could grasp both outer or inner RF （Radio-Frequency） radiations and substrate parasites.

A Pragmatic Observational Feasibility Study on Integrated Treatment for Musculoskeletal Disorders：Design and Protocol

Background：Musculoskeletal disorders（MSD） comprise a wide range of conditions,associated with an enormous pain and impaired mobility,and are affecting people＇s lives and work.Management of musculoskeletal disorders typically involves a multidisciplinary team approach.Positive findings have been found in previous studies evaluating the effectiveness of complementary therapies,though little attention has been paid to evaluating of the effectiveness of integrated packages of care combining conventional and complementary approaches for musculoskeletal conditions in a National Health Service（NHS） setting.Objective：To determine the feasibility of all aspects of a pragmatic observational study designed：（1） to evaluate the effectiveness and cost effectiveness of integrated treatments for MSDs in an integrated NHS hospital in the UK;（2） to determine the acceptability of the study design and research process to patients;（3） to explore patients＇ expectation and experience of receiving integrated treatments.Methods：This is an observational feasibility study,with 1-year recruitment and 1-year follow-up,conducted in Royal London Hospital for Integrated Medicine,University College London Hospital Trust,UK.All eligible patients with MSDs newly referred to the hospital were included in the study.Interventions are integrated packages of care（conventional and complementary） as currently provided in the hospital.SF-36 Health Survey,short form Brief Pain Inventory,Visual Analogue Scale,and modified Client Service Receipt Inventory will be assessed at 4/5 time points.Semi-structured interview/focus group will be carried out before treatment,and 1 year after commence of treatment.Discussion：We intend to conduct a pragmatic observational study of integrated medical treatment of MSDs at a public sector hospital.It will inform the design of a future trial including recruitment,retention,suitability of the outcome measures and patients experiences.

Efficient approach and application of the Green's functions in spatial domain in multilayered media

Based on the dipole source method, all components of the Green＇s functions in spectral domain are restructured concisely by four basis functions, and in terms of the two-level discrete complex image method （DCIM） with the high order Sommerfeld identities, an efficient algorithm for closed-form Green＇s functions in spatial domain in multilayered media is presented. This new work enjoys the advantages of the surface wave pole extraction directly carried out by the generalized integral path without troubles of that all components of Green＇s function in spectral domain should be reformed respectively in transmission line network analogy, and then the Green＇s functions for mixed-potential integral equation （MPIE） analysis in both near-field and far-field in multilayered media are obtained. In addition, the curl operator for coupled field in MPIE is avoided conveniently. It is especially applicable and useful to characterize the electromagnetic scattering by, and radiation in the presence of, the electrically large 3-D objects in multilayered media. The numerical results of the S-parameters of a microstrip periodic bandgap （PBG） filter, the radar cross section （RCS） of a large microstrip antenna array, the characteristics of scattering, and radiation from the three-dimensional （3-D） targets in multilayered media are obtained, to demonstrate better effectiveness and accuracy of this technique.