Cadence Design Systems

About: Cadence Design Systems is a company organization based out in San Jose, California, United States. It is known for research contribution in the topics: Circuit design & Routing (electronic design automation). The organization has 3139 authors who have published 3745 publications receiving 66410 citations. The organization is also known as: Cadence Design Systems, Inc.

Fast simulation algorithms for RF circuits

Abstract: RF integrated circuit designers make extensive use of simulation tools which perform nonlinear periodic steady-state analysis and its extensions. However, the computational costs of these simulation tools have restricted users from examining the detailed behavior of complete RF subsystems. Recent algorithmic developments, based on matrix-implicit iterative methods, is rapidly changing this situation and providing new faster tools which can easily analyze circuits with hundreds of devices. In this paper we present these new methods by describing how they can be used to accelerate finite-difference, shooting-Newton, and harmonic-balance based algorithms for periodic steady-state analysis.

The best of both worlds: the efficient asynchronous implementation of synchronous specifications

Abstract: The desynchronization approach combines a traditional synchronous specification style with a robust asynchronous implementation model. The main contribution of this paper is the description of two optimizations that decrease the overhead of desynchronization. First, we investigate the use of clustering to vary the granularity of desynchronization. Second, by applying temporal analysis on a formal execution model of the desynchronized design, we uncover significant amounts of timing slack. These methods are successfully applied to industrial RTL designs.

Intravenous acetaminophen for pain after major orthopedic surgery: an expanded analysis.

Abstract: Background and Methods: From the time that Sinatra et al. (Anesthesiology. 2005;102:822) was published to FDA apaproval of intravenous (IV) acetaminophen, an expanded analysis of the original raw study data became necessary for the regulatory submission. The following analyses were conducted: (1) sum of pain intensity differences over 24 hours (SPID24) using currently accepted imputation methods to account for both missing data and the effects of rescue; (2) efficacy results after the first 6 hours; (3) effects of gender, race/ethnicity, age, weight, surgical site, ASA Class, and serotonin antagonists; and (4) a stepwise regression analysis of why adverse events of nausea and vomiting were numerically (although not statistically) higher in the IV acetaminophen group compared with placebo. Results: Sum of pain intensity differences over 24 hours using a 0- to 100-mm visual analog scale was statistically significantly (P < 0.001) in favor of IV acetaminophen (n = 49) compared with placebo (n = 52). Time to rescue was found to be 3.9 and 2.1 hours, respectively, for total hip and knee arthroplasty compared with 0.8 hours for the placebo group. Rescue medication consumption, requests, and actual administration were all significantly lower in the IV acetaminophen group compared with placebo for each dosing interval, except in the 6- to 12-hours interval where a numerical trend was observed. Analysis of various subset variables demonstrated similar efficacy for each variable. A stepwise regression analysis demonstrated that AE reports of nausea and vomiting were most likely due to prerandomization events, particularly opioid consumption and presence of nausea prior to randomization. Conclusion: Repeated-dose 24-hours end points were found to be as robust as previously published results. IV acetaminophen efficacy and safety appeared to be unaffected by specific subset variables.▪

Ultra-low power switching regulator method and apparatus

Abstract: A low-power controller for a discontinuous switched mode power converter. The controller has an inductor current sensing circuit to measure the inductor current flowing through an inductive charge storage element as well as an output voltage sensing circuit to monitor output voltage. The controller monitors both the converter output voltage and the inductor current and uses this information to modulate a peak inductor current trip point and controller switching frequency according to a control law curve in order to regulate converter output voltage. The controller prevents the switching frequency from falling below a predetermined minimum frequency. The control law curve is selectable to specify controller operation according to a desired combination of minimum switching frequency and maximum peak inductor current.