high frequency sawtooth oscillator

Discussion in 'General Electronics Chat' started by DominusDRR, May 25, 2009.

  1. DominusDRR

    Thread Starter Member

    May 25, 2009
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    Is there a diagram of a high frequency sawtooth oscillator? 100MHz​

    I'm going to use HFA1109 Amp Op.​

    Fabián​
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    At that frequency it is going to be hard. You know how harmonics relate to waveforms, right?
     
  3. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    Indeed....that's even pushing the recovery time of a xenon relaxation oscillator!

    eric
     
  4. beenthere

    Retired Moderator

    Apr 20, 2004
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    Perhaps you could say why a sawtooth waveform is necessary?
     
  5. DominusDRR

    Thread Starter Member

    May 25, 2009
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    Yes. Definitely, I know about harmonics. I am not an expert in high frequency electronics, but I hope I will generate voltage signal​
     
  6. DominusDRR

    Thread Starter Member

    May 25, 2009
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    I need to generate this signal to compare with other lower frequency signal. Something like a PWM or SPWM

    Fabian​
     
  7. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    Why do you need 100 Mhz?
    What is the maximum frequency you use for the other comparing part?

    Greetings,
    Bertus
     
  8. DominusDRR

    Thread Starter Member

    May 25, 2009
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    The other is 1MHz @ 10 MHz
     
  9. Wendy

    Moderator

    Mar 24, 2008
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    Thing is, you're frequency response is going to be way past 500Mhz. That is the 5X harmonic. For a decent waveform you'll need really high frequency response.

    At that frequency making a square wave is even harder, for the same exact reason. Square waves are usually used to generate triangle waves, but I think we can say this won't be practical at this frequency. The logic family ECL operates in this region, and gets around it by deliberately rounding the edges. A continuous logic chain in ECL resembles a sine wave more than a square wave.
     
  10. DominusDRR

    Thread Starter Member

    May 25, 2009
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    And.. a DDS. Is it best?
     
  11. bertus

    Administrator

    Apr 5, 2008
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  12. millwood

    Guest

    that's an interesting design.

    1) the mcu takes usb signal and sends out i2c. I would love to see their source code, :) for that.

    2) the si570 is quite amazing. programmable oscillator. conceiveably, you can just take a mcu to control that with up/down buttons but controlling it with a pc through usb must be fun.
     
  13. millwood

    Guest

    the way they do tempco compensation is very smart.

    it looks like a well thought-out and well designed package.
     
  14. eblc1388

    Senior Member

    Nov 28, 2008
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