MSP430F6726A: Regarding 32K crystal accuracy

Hi,

The load caps need to be good enough to get the crystal oscillating. As long as the crystal starts(even if the loading caps are off by a few pFs) it shouldn't have a significant impact on the power consumption.

BR,
Leo

Hi,

Thank you for your response.

However, the frequency of 32KHz changes by changing the setting of the XCAP register.

At this time, setting XCAP = 00 and the oscillation frequency of the 32K crystal shifts by about 200Hz,

but the current consumption also becomes considerably larger than when other XCAP settings are made.

 What is the reason for this?

Best regards,

Hi,

You can find more information on 32kHz crystal integration here:

https://www.ti.com/lit/an/slaa322d/slaa322d.pdf

Section 4.1 describes the relationship between load capacitance and oscillating frequency. 

The data sheet also talks about setting XCAP in section 5.8.3.  

BR,

Leo