Replacing MEGA 2560 standard crystal with higher precision crystal

Hi all,

I've read some articles on the forum about replacing crystals (and what the impact could be)

But I did'nt find a satisfying answer to my question.

1° - did anyone ever did it with succes (D-I-Y)? 2° - what would be a higher precision crystal for the MEGA 2560 ADK 3° - are there any "hands-on" articles on this issue (on the forum - or the internet), where I could learn to do something like that myself 4° - if its impossible, is there an alternative (higher speed MCU? still compatible with the arduino IDE)

For my project i can be no more than 50PPM off, it's a high precision,competition chronometer

I've read some articles that claim that the Mega 2560 is something like 1237ppm off !!?? Is this true? how does one measure something like that?

Grtz, Yves

Choice of 10ppm crystals

This one will do:- 16 MHz 10 ppm

3° - are there any "hands-on" articles on this issue (on the forum - or the internet), where I could learn to do something like that myself

I doubt it, it is just so simple. Unsolder the old one and replace it.

Hi Grumpy_Mike,

thanks for the specsheets on this one...

should I change the capacitor(s) too? or would that be OK with the original ones?

Grtz, Yves

YvesD: Hi Grumpy_Mike,

thanks for the specsheets on this one...

should I change the capacitor(s) too? or would that be OK with the original ones?

Grtz, Yves

There are no capacitors on the original part (which is a resonator).

YvesD:
I’ve read some articles that claim that the Mega 2560 is something like 1237ppm off !!?? Is this true? how does one measure something like that?

What I did, was compare millis() with a 1PPS signal from a GPS receiver.

should I change the capacitor(s) too?

Data sheet says:-

18 pF,

You should be able to sneak them in at the resistor adjacent to the crystal, by scraping off some resist to expose the ground plane. That's if the crystal is the same size as the resonator, I forgot to look. But it looks straightforward.