Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Filter Benchmarking system?

  1. Apr 16, 2017 #1
    Hi,
    Say I have a design for a filter, is there a method of bench-marking it's attenuation over a variety of loads and types of harmonics? (or even common and differential noises)

    For instance, say I wanted to compare a filter to an LC filter or a π filter, how does one evaluate how much better or worse these are to each other and to other filters?

    Cheers
     
  2. jcsd
  3. Apr 17, 2017 #2

    berkeman

    User Avatar

    Staff: Mentor

    In simulation, you would use one of the SPICE packages, preferably one that lets you use Monte Carlo variations to explore what happens over component tolerances.

    For actual circuits, you can use a Spectrum Analyzer with Tracking Generator Output to scan the input signal to the filter and plot the output response (gain, not phase). Alternately, you can use the Gain-Phase measurement capability of an Impedance/Gain-Phase analyzer instrument like the HP 4194 (we have several in our Lab)...

    http://www.testequipmentdepot.com/usedequipment/images/4194a.jpg
    4194a.jpg
     
  4. Apr 18, 2017 #3
    Thanks for the reply.
    Also, is there any testing methodology for performing assessment with more basic equipment like a signal generator and an oscilloscope?
    Cheers
     
  5. Apr 18, 2017 #4

    berkeman

    User Avatar

    Staff: Mentor

    Yes, you can certainly do basic testing with a signal generator and oscilloscope. You just end up using the cursors on the 'scope to make your amplitude and phase shift measurements, and putting them into a spreadsheet by hand for plotting. Display both the input and output waveforms on the display and make your measurements at frequencies of interest. I did that plenty back in my school days, before I had access to Gain-Phase instruments like the HP 4194. :smile:
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Filter Benchmarking system?
  1. System and filter (Replies: 1)

  2. Voltage Filter (Replies: 2)

  3. Highpass filter (Replies: 14)

Loading...