Enhancing its Web-based tools that help engineers design with its products, National Semiconductor has stitched together its power and analog Webench tools into a more or less seamless design environment.
The existing Webench switching converter tool now interfaces with a trio of tools that start by matching analog-to-digital converters (ADCs) and signal-conditioning amplifiers and go on to complete the signal path with multi-order anti-aliasing filters. The signal path tools are quite flexible, as circuit designers can start either with a set of specifications for the signal conditioning amplifier or the ADC. Filter options include Bessel, Butterworth, Chebyshev, Equiripple, and transitional Gaussian.
The graphical user interface creates a great learning tool, since students can graphically compare frequency, step, and phase response/group delay for various configurations, even taking component tolerances into account. Then it's on to a simulation model of the entire signal chain. For working designers, next-day delivery of a complete prototyping parts kit is possible.
At this point, the Webench tools handle designs based on sample rates from 50 ksamples/s to 1 Msample/s and third-order filters. By January, speeds will be up to 100 Msamples/s and filters up to ninth order. Use of the tools is free. Log on at www.national.com/appinfo/webench/scripts/my_webench.cgi/.