Hi,
We have our product with TI chip MSP430FR2433IRGER sometimes doesn't work, or it works but don't work again.
It is a crystal issue? We are using AS75-32768D-PF 32.768kHz Crystal, 1.6x1.0mm 9pF 20ppm -40/+85°C ESR max 90k.
Is the the crystal well chosen?
The configuration for the crystal is:
- AGC is enabled (XT1AGCOFF = 0)
- XT1DRIVE value is 3 (default value)
- Low frequency mode
- XT1AUTOOFF = 1
We detect the duty cycle is near 50%.
We test the crysal's stability according your application note with negative resistance (SLAA322D §4.2),
we found the safety factor >6. Our design is very safe according to the application note.
Please don't hesite to comment our test.
Thank you in advance
Best regards
Liang