Hi,
So was thinking about using this crystal ABM3-8.000MHZ-B4Y-T for a prototype application but then i realized that the device isn’t heavily dependent on
accurate timing or perhaps it does ??. Basically it’s a device that in operation mode,
works for 2 hours max and depending on several external factors/conditions and battery health, the work time is automatically changed.
I have implemented this around the A-Star 8MHz board and a custom board running the A star bootloader several times and conditions without any issues.
the timing has been extremely precise when i run it right next to my smartphone’s clock
and it doesn’t lag behind or lead. maybe one of these situation might be present
but i have not run this application for more than 8hours so i wouldn’t know.
Thus, I wondered, perhaps looking for the perfect crystal clock is irrelevant.
I could simply use a similar low cost 8MHz crystal with a built-in load capacitance ??
the A- Star’s m328p crystal oscillator looks like a murata product and
I know microchip m328p datasheet recommends 11 - 22pF load capacitance
so i was wondering if CSTNE8M00G55Z000R0 would do the trick ?? 33pF/2 = 16.5pF which is in the 11 - 22pF range.
If there is no need for very precise timing, then a resonator should work. We do not commit to specific crystals or resonators on the A-Stars, and helping you choose one for your own design is generally beyond the scope of our technical support, but from a quick glance, the resonator you linked to would probably be okay to use with the ATmega328PB.
-Claire