EDN Access -- 8.03.95 design features

Design Features: August 3, 1995

Cover Story
PCs and telephones start to merge	All the hardware and software building blocks are there to turn your PC into a telephone. Those blocks still have rough edges, how-ever, so you have to fit them together carefully —Richard A Quinnell, Technical Editor
Design Features The hottest new technologies and the latest design techniques to help you work efficiently and effectively.
Converters restructure communication architectures	The superheterodyne-receiver structure has served designers well for more than 70 years. Now, its reign is being challenged by A/D converters, which push digital circuitry closer to the antenna. As a result, you must understand a different set of converter specifications, as well as the hardware trade-offs of a software-based solution. —Bill Schwebber, Technical Editor
Use your DSO to measure elusive waveform variations	The subtleties of how your DSO works can be just as important as the "banner" specs. The time you spend learning about the instrument's performance details can help you to spot waveform anomalies that you never suspected. —Robert Witte, Hewlett-Packard Co
Fixed or floating? a pointed question in DSPs	Designers considering DSP applications must first decide whether to commit their designs to fixed- or floating-point DSPs. The answer may seem to be a trade-off between cost and performance. However, designers must carefully consider a variety of factors before choosing a DSP. —Jim Larimer and Daniel Chen, Texas Instruments
Improved circuit-analysis techniques require minimum algebra	When designing circuits, most analog engineers rely largely on experience and trial-and-error methods, eschewing much of the matrix algebra they learned in college. Using the Extra Element Theorem, however, is a helpful analytical technique that can yeild insight into network design. —Vatché Vorpé, Jet Propulsion Laboratory, California Institute of Technology
Isochronous LAN standard brings real-time video collaboration to the desktop	IEEE-802.9a isoEthernet is the logical choice as the LAN standard of the future. It is interoperable with existing standards. It can provide seamless connectivity over public ISDN networks. And it can isolate local multimedia applications from a company's normal packet LAN/router data flow, thereby maximizing the performance of both local ISDN services and Ethernet packet traffic on the same LAN. —Rich Brand, National Semiconductor Corp