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Text File  |  1997-06-29  |  2KB  |  60 lines

  1. <html>
  2.  
  3. <head>
  4. <title>HwB: Active Filter: Butterworth 24dB Lowpass</title>
  5. <meta name="Author" content="Joakim Ögren">
  6. <meta name="Description"
  7. content="Formulas for a 4th order Butterworth active lowpass filter.">
  8.  
  9. <meta name="Keywords"
  10. content="HwB, pinout, hardware, butterworth, filter, active, lowpass, 4th, 24">
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  14. </head>
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  18. link="#0000EE" vlink="#551A8B" alink="#FF0000">
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  21. <p align="center"><a href="menu_Misc.html"><img
  22. src="images/mini_Back.GIF" alt="GoTo Misc" border="0" width="64"
  23. height="48"></a><img src="images/menu_Misc.GIF" alt="MISC"
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  27.  
  28.  
  29. <h1>Active Filter: Butterworth<br>
  30. (4th order, 24 dB/octave, Lowpass)</h1>
  31.  
  32. <p><img src="images/misc_ActiveFilter4L.GIF" align="bottom"
  33. width="371" height="121"></p>
  34.  
  35. <p>R=4.7k-10 kOhm<br>
  36. Ca=1.0824/(2*pi*Fc*R)<br>
  37. Cb=0.9239/(2*pi*Fc*R)<br>
  38. Cc=2.6130/(2*pi*Fc*R)<br>
  39. Cd=0.3827/(2*pi*Fc*R)</p>
  40.  
  41. <p><font size="2"><i>Units: R [Ohm], Cx [F], Fc [Hz]</i></font></p>
  42.  
  43. <address>
  44.     <font size="2">Contributor: </font><a
  45.     href="mailto:qtech@mailhost.net"><font size="2">Joakim Ögren</font></a>
  46. </address>
  47.  
  48. <address>
  49.     <font size="2">Source: ?</font>
  50. </address>
  51.  
  52.  
  53. <address>
  54.     <font size="1">Please send any comments to </font><a
  55.     href="mailto:qtech@mailhost.net"><font size="1">Joakim Ögren</font></a><font
  56.     size="1">.</font>
  57. </address>
  58.  
  59. </body>
  60. </html>