The power.national.com collection of interactive online design tools, launched by National Semiconductor last fall, has been revamped. Its updated Webench 2.0 should accelerate development through automated design creation, virtual physical layouts, and Web-based simulations. This version incorporates three major changes: the EasyPLL tool for simulating PLL designs, an enhanced version of the power simulation tool unveiled last year, and the WebTHERM thermal simulator.
"The Webench enables a designer to choose parts, create a design, analyze it, and then build it," explains Phil Gibson, vice president of Web marketing at National. "The objective is to accomplish an optimal design in the shortest possible time. The new paradigm is going from from concept to a working prototype in few clicks."
EasyPLL targets designers of RF/analog front ends based on phase-locked loops (PLLs) for cell phones or other wireless communication systems. To access EasyPLL, National has created a separate Web location, wireless.national.com. En-gineers can enter specifications and select PLLs, voltage-controlled oscillators (VCOs), and passive components from a catalog of over 350 devices. Users create the design by entering loop-filter parameters and analyzing the design for loop-filter performance in terms of phase noise and margin, Bode plots, and lock time. All this can be done in minutes. Once satisfied, designers can order samples online.
For power-supply designers, the refurbished power.national.com offers the improved WebSim and the new WebTHERM. The enhanced WebSIM power-design flow now includes "switchers made simple" software. Developed in cooperation with Flomerics Corp., a company based in the U.K., WebTHERM combines physical layout with thermal modeling to generate full-color thermal images of the board design in minutes.
Together, a power designer can pick the desired circuit topology, select from over 2000 components including passives from dozens of vendors, perform online design analysis and simulation, and then create physical layouts and develop prototypes. In this process, engineers provide an input voltage range, an output voltage range, and the maximum current. Using these parameters, designers then select the switching regulator, analyze it, and generate the bill of materials for the intended design. The bill-of-materials table provides a list of part numbers and their manufacturers, with links to the distributors for purchasing.
The building process involves pc-board layout and thermal analysis. Sample evaluation boards and layout files are available. WebTHERM generates color thermal images of the populated board (see the figure). By calculating the heat transfer and interaction between components on the board and the surrounding environment, WebTHERM generates junction temperatures for the components and a thermal envelope for the design.
National says WebTHERM is faster and more accurate than the traditional infrared approach. Plus, it lets designers adjust environmental and air-flow parameters to optimize heat dissipation and electrical performance. "Readjustments and resimulation is only a matter of a few clicks," Gibson says. "In effect, these tools close the loop from online design to purchasing and prototyping."
The tool set can be accessed via Nationals' Web site, www.national.com, or by going directly to the desired site. For power-supply design, go to www.power.national.com. For wireless EasyPLL design, point your browser to www.wireless.national.com.