Using an external MEMs oscillator as 32.768KHz source

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SD_Michael
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Using an external MEMs oscillator as 32.768KHz source

Hi,

We have a question related to the DA14682 and the usage of an external 32.768KHz source.

For space-saving reasons, we would like to provide the 32.768KHz signal using an external MEMs oscillator (SiTime SiT1552). We intend to use this oscillator according to the guidelines in section 5.3.2 of "AN-B-061 DA1468x Application hardware design guidelines_v1.7."

Within section 5.3.2, there is an applicable paragraph that states:
"For applying a 32.768 KHz square wave clock signal having an amplitude of 1.8Vpp from an external source (e.g. MCU) to the P2_0 pin of the DA1468x, the following procedure needs to be applied..."

However, we wanted to ask a clarifying question related to P2_1:
In this scenario of providing the external 32.768 square wave source to P2_0, what should we do with P2_1 (XTAL32KM)? Can we leave it floating?

Thanks,
Michael

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PM_Dialog
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Hi SD_Michael,

Hi SD_Michael,

If you use an external source for the 32.768 KHz square wave clock signal generation, you use only the P2_0 and leave the P2_1 unconnected.

Thanks, PM_Dialog

SD_Michael
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Thanks for the clarification!

Thanks for the clarification!