1,720,967 research outputs found
A 5-V Switch for Analog Multiplexers With 2.5-V Transistors in 28-nm CMOS Technology
No full textDespite the scaling of the supply voltage of deep-submicrometer CMOS technologies, many applications still require to deal with off-chip signals in high-voltage domains (e.g., 3.3 and 5 V). Hence, foundries offer fabrication processes with voltage-tolerant transistors, which are inherently protected from the electrical stress, at the expenses of compromising their performances, reducing the design portability, and augmenting the production costs in case of the customization of the process. As an alternative, circuit techniques, such as cascoding, adaptive biasing, and voltage shifting, result effective in designing analog circuits, such as amplifiers and voltage drivers at high supply voltage with voltage-scaled transistors. This article presents the architecture of a switch for analog multiplexers (MUXs) able to handle signals up to twice the nominal supply voltage of the employed transistors. To validate the circuit choice, a switch for a 5-V MUX has been designed with 2.5-V transistors in 28-nm CMOS technology. The comparison with a benchmark architecture with tailored 5-V devices shows that an about three times larger area and 4- μ A static current demand have to be considered. Moreover, an accelerated degradation test (ADT) showed a similar decay of the features of both types of switches
A 1.6-V Tolerant Multiplexer Switch with 0.96-V Core Devices in 28-nm CMOS Technology
No full textThe reduction of the nominal supply voltage of CMOS technologies with scaling comes with the decrease of the maximum tolerable voltage of the devices. This poses challenges in implementing circuit blocks that are compliant with standardized communication protocols or deal with off-chip signals in voltage domains larger than the nominal supply (e.g., 1.8 V, 3.3 V, 5 V). Design techniques such as cascoding, voltage shifting and adaptive biasing are effective at removing the need for customized voltage resistant input/output (I/O) devices since they prevent intolerable voltage drops. However, at the input of multiple-channel blocks, the design of switches of multiplexers results critical as the input and the output nodes can assume values beyond the signal range, causing harmful biasing configurations. This paper presents the architecture of a switch for input channel multiplexers able to handle signals up to twice the nominal supply voltage of the employed devices. Its effectiveness has been proved by implementing a 1.6V switch with the core MOS transistors of the 28nm CMOS technology with 0.96V nominal supply voltage. The comparison with a benchmark switch based on 1.8V I/O devices showed that both a larger area (slightly more than twice) and static current consumption ( 40mu text{A} ) are required
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Wideband chirp generation techniques in digital phase-locked loops
No full textIn this paper in-depth analysis and comparison of two popular FM techniques, namely, two-point modulation and pre-emphasis of the modulation signal are presented. Both modulation enhancement techniques were implemented in the time domain model of an all-digital phase-locked loop (ADPLL). Their performance is evaluated based on Matlab simulations for different type of chirps. Obtained results show that chirps with the period of 0.1ms and peak-to-peak bandwidth of 1GHz can be generated with linearity better than 1% by employing either of these techniques. Additionally, advantages of two-point modulation with respect to ADPLL building block requirements are demonstrated
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Analytical Modeling of Jitter in Bang-Bang CDR Circuits Featuring Phase Interpolation
Full text linkThis article proposes compact expressions for the jitter in clock and data recovery (CDR) circuits based on bang-bang phase detector including the phase noise of the transmitter and receiver oscillators as well as the quantization noise associated with the finite number of phases of the phase interpolator (PI) that align the receiver clock to the incoming data. Different approaches to perform the Early/Late detection on deserialized data and edge samples are compared: the use of majority voting degrades the CDR bandwidth, increasing the impact of the clock jitter on the CDR jitter; on the other hand, counting the single Early/Late occurrences does not degrade the bandwidth but increases the noise related to the finite phases of the PI. The proposed analytical formulas are validated against event-driven behavioral simulations of the CDR system including free-running oscillators as well as phase-locked loop (PLL) for clock generation
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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