Choosing a crystal.

Discussion in 'Embedded Systems and Microcontrollers' started by Gibson486, Jun 16, 2016.

  1. Gibson486

    Thread Starter Active Member

    Jul 20, 2012
    I am trying to pick a crystal for an ARM processor.

    Originally, I was going to use this:

    but I ran out of space. As a result, I am thinking of using this:

    I am sort of confused, because I am not sure what I lose from going to one to another. I noticed that the first one listed Microprocessors as an application, but I am guessing that is for marketing and the other one will work as well? Also, I am assuming that the ARM cannot drive over 200 uW spec on the 2nd crystal. I am hoping that it really does not matter just as long as I get the caps to go with it correctly.
  2. joeyd999

    AAC Fanatic!

    Jun 6, 2011
    Underdriving a crystal is rarely a problem. Overdriving fractures the crystal. The second choice should work fine.

    Crystal circuits on modern MCUs are easy today. Not like the old days. Just about anything works well.
  3. Gibson486

    Thread Starter Active Member

    Jul 20, 2012
  4. AlbertHall

    AAC Fanatic!

    Jun 4, 2014
  5. dannyf

    Well-Known Member

    Sep 13, 2015
    It is unlikely wise to assume. In general, you look for frequency, stability, packaging, price, etc.

    I typically look for small load capacitance, 5 or 6pf ones are good in that the parasiticc capacitance would be sufficient.