The Designer's Guide Community
Forum
Welcome, Guest. Please Login or Register. Please follow the Forum guidelines.
Sep 30th, 2024, 6:14am
Pages: 1
Send Topic Print
pure sine wave generator (Read 1659 times)
analog2000
Junior Member
**
Offline



Posts: 21

pure sine wave generator
Jul 22nd, 2007, 7:36am
 
Hello,
I have to design a blockthat can generate spectrally pure sine waves voltages around 10KHz. I am contemplating using a high Q bandpass filter to convert a square wave into a sine wave, would anyone like to share their thoughts about this problem ?
thanks a lot
Best Regards
analog2000
Back to top
 
 
View Profile   IP Logged
jp314159
New Member
*
Offline



Posts: 3

Re: pure sine wave generator
Reply #1 - Aug 2nd, 2007, 1:07pm
 
Generate a clock signal at (say) 16x the 10kHz, and use a DAC to stairstep approximate the sine. At 16x, you will only have harmonics present that are > 160kHz, and so very easy to filter.

At 16x, in fact,  you only need 4 or 5 DAC values, assuming you do the 180°-360° portion by inverting the first half. You can build the DAC with just a string of a few resistors and tapping off (taps at sin(15°), sin(30), sin(45) etc.). Send the output of the DAC simultaneously through 2 opamps -- one a follower, and the other a gain of -1. Using logic, alternativerly select the +1 and the -1 path.


Back to top
 
 
View Profile   IP Logged
Pages: 1
Send Topic Print
Copyright 2002-2024 Designer’s Guide Consulting, Inc. Designer’s Guide® is a registered trademark of Designer’s Guide Consulting, Inc. All rights reserved. Send comments or questions to editor@designers-guide.org. Consider submitting a paper or model.