SMT resonator

Can anyone suggest an 16mhz SMT resonator?

Are you hand soldering it yourself or is the device pick and placed by machine for flow soldering?

What tollerance does it need to be?

db2db: Can anyone suggest an 16mhz SMT resonator?

If it's for a microcontroller board (or an AVR circuit) I suggest:

  • Use a CRYSTAL, not a resonator. Resonators are not stable with temperature changes.
  • Use a frequency value that gives you an accurate serial baud rate such as 18.432 MHz.

The first thing I do when I get a new Arduino board is remove the 16 MHz. resonator and install a 22.1184 MHz. SMT crystal. 22.184 works just fine, but it's probably best you don't push your luck.

Riva:
Are you hand soldering it yourself or is the device pick and placed by machine for flow soldering?

What tollerance does it need to be?

If he’s going to use a RESONATOR, then the concept of “tolerance” is rather a joke… :slight_smile:

Since a crystal need two caps, why would anyone choose that unless timing is a big issue for the application?

I haven't seen serial issues using resonators, have you?

Yes, PNP, though some hand solder for prototypes, so nice if had leads beyond the body, though not essential.

Since a crystal need two caps,

So what great disadvantage is that? There seems to be an aversion amongst beginners in using passive components. Can you not afford $0.01 each?

I haven't seen serial issues using resonators, have you?

Yes and again so what?

unless timing is a big issue

This is a real time processor, timing is always an issue unless you are doing something trivial.

The difference between 0.5% accuracy and 0.002% accuracy is often important. If you want to keep wallclock time 0.002% (20ppm) means 10 seconds or so per week, 0.5% is an hour a week...

Anyway you can get a complete crystal oscillator in one package, no extra caps needed.

Actually the caps are a lot less than a cent each for production quantities I suspect, the cent is for the PCB area they take up - much more expensive than the components for typical passives!

The reason to not use more parts: another sku to stock, another PNP placement, and extra connections to fail. I've seen crystals that were quite picky about the caps chosen.

Resonators are ~ 50c single piece. Crystals 75 cents.

If I revise my question to ask for a complete crystal oscillator or osc that needs caps, do you have suggestions?

Since you do not seem to have any particular requirements in mind, any will most likely work fine.