Groovy Posted April 29, 2004 Report Share Posted April 29, 2004 Hello everyone...i was actually supposed to be doing another project..but it didnt go as planned. so now im doingA stand alone sine wave generator using Atmel chipIt requires to run at frequency of at least 25kHz, but the harmonic distortion is not critical and may be as high as 3%.Preliminary Specifications(i) The device will operate from a dual supply of nominally 12V, onboard power regulation will be used where required.(ii) The microcontroller used will be the Atmel AT90S2313 employing a 4MHz resonator as the clock source.(iii) The output voltage required is 0dBm into 600 Ohms the output impedance is of course 600 Ohms.(iv) Some means of adjusting the frequency will be provided. (v) PCB size will not exceed 80mm by 50mm.So if anyone has any ideas..please let me know..me only a beginne :Dr...so any websites to learn would be great as well..thanx alot.thanx to everyone... Quote Link to comment Share on other sites More sharing options...
hotwaterwizard Posted April 29, 2004 Report Share Posted April 29, 2004 AT90S2313 Here are some links that may help!Datasheethttp://www.atmel.com/dyn/resources/prod_documents/DOC0839.PDFApplication Noteshttp://www.atmel.com/dyn/resources/prod_documents/doc2542.pdfhttp://www.qsl.net/zl1bpu/micro/Noise-Pulse/Noise-Pulse.htmhttp://users.cableaz.com/~cappels/dproj/syncdet/syncdet.htmlhttp://www.atmel.com/dyn/resources/prod_documents/doc2521.pdfhttp://www.circuitcellar.com/library/print/0201/ball127/ball-127.pdf Quote Link to comment Share on other sites More sharing options...
Groovy Posted April 29, 2004 Author Report Share Posted April 29, 2004 Thank you hotwaterwizard...that should give me a start.. Quote Link to comment Share on other sites More sharing options...
MP Posted April 29, 2004 Report Share Posted April 29, 2004 Groovy, are you making a sine wave inverter using the "magic sine waves" principal? If so, there was a discussion at Electronics Forums / Circuit/General Requests / True Sine Wave Inverter on this forum. You will find links posted there as well.MP Quote Link to comment Share on other sites More sharing options...
AVRFreakMan Posted April 29, 2004 Report Share Posted April 29, 2004 Groovy,you haven't seen this?http://www.myplace.nu/avr/minidds/index.htmKyriakos Quote Link to comment Share on other sites More sharing options...
audioguru Posted April 29, 2004 Report Share Posted April 29, 2004 Groovy,Here is a project that uses a mini-micro to digitally bandpass-filter its internally-divided clock and over-sample it. Although it was limited to a max freq of 20kHz it may give you ideas for use with faster chips. The project is here:http://www.web-ee.com/Schematics/Digital_Sine/DigitalSine.htm Quote Link to comment Share on other sites More sharing options...
audioguru Posted April 29, 2004 Report Share Posted April 29, 2004 Here is a programmable digital sine-wave chip developed by Fairchild awhile ago for telcos. They say that it uses "no external components". I haven't checked its availability. They talk about the phase-accumulators having interference causing distortion readings (0.1%) to be higher than it actually is, so I suspect that is has some phase-jitter. The data sheet is here:http://www.fairchildsemi.com/ds/ML/ML2035C.pdf Quote Link to comment Share on other sites More sharing options...
MP Posted April 30, 2004 Report Share Posted April 30, 2004 As AVRFreakMan has said...check out the link.MP Quote Link to comment Share on other sites More sharing options...
Kevin Weddle Posted April 30, 2004 Report Share Posted April 30, 2004 A sine wave is sometimes made from a triangle wave. This would mean the use of an integrator. I would use a transistor and a capacitor on the collector to construct the triangle wave. Then a simple filter would be required. The filter would be to attenuate the low frequency of the triangle. Use an oscilloscope. Simple. Quote Link to comment Share on other sites More sharing options...
audioguru Posted May 1, 2004 Report Share Posted May 1, 2004 Kevin,You can also make a sine-wave from a square wave, just filter out the harmonics. Then you don't need an integrator.Your simple filter attenuates the HIGH frequency harmonics by rounding-off the sharp corners. Quote Link to comment Share on other sites More sharing options...
Kevin Weddle Posted May 1, 2004 Report Share Posted May 1, 2004 I would bet there is a debate regarding sinewave generation. I have seen an example in this forum that uses a square wave, but with an added DC level during the middle part of the transistion. They called this a modified sinewave. I agree that a squarewave can be used to make a sinewave. But I know that an oscillator most resembles a triangle wave. Quote Link to comment Share on other sites More sharing options...
Groovy Posted May 2, 2004 Author Report Share Posted May 2, 2004 Thank you everyone so much....thats shud give me a good start.will keep u guys posted :)thank you again Quote Link to comment Share on other sites More sharing options...
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