Connect with us

frequency synthesizer

Discussion in 'Electronic Design' started by Lost'n Found, Aug 8, 2006.

Scroll to continue with content
  1. Lost'n Found

    Lost'n Found Guest


    I was reading about frequency synthesizers and it seems I am missing some

    These synthesizers can generate higher frequency. On the specification
    sheets, I read that we can divide the reference frequency by certain
    factors. My question is: If we are dividing the frequency, why are we
    getting much higher frequencies at the output?
  2. Tim Wescott

    Tim Wescott Guest


    You can find out amazing amounts of stuff doing web searches, like on
    "frequency synthesizer theory".


    You can only get frequencies out that are multiples of the reference
    frequency going to the phase detector (unless you're using a fractional
    N synthesizer -- You can find out amazing amounts of stuff doing web
    searches). It's easier to make a good clock source from a crystal, so
    if you want to have a synthesizer work in 5kHz steps you'll want to
    generate a clock at (say) 5MHz, divide it by 1000, then synthesize a
    frequency from that in 5kHz steps.


    Tim Wescott
    Wescott Design Services

    Posting from Google? See

    "Applied Control Theory for Embedded Systems" came out in April.
    See details at
  3. Rich Grise

    Rich Grise Guest

    This might be helpful:
    That's just one of "about 381,000 for 'frequency synthesizer'" at"frequency+synthesizer"

    Have Fun!
  4. Andrew Holme

    Andrew Holme Guest

    Because we divide down and then multiply up. A common reason for doing so
    is to reduce the step size / comparison frequency.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day