LFCLK accuracy in smart beacon kit

[oceanide]

Dear all,

I have a question on the LFCLK accuracy in the smart beacon kit, which is pca20006. When I see the specification of LFCLK crystal 32.768kHz, this crystal has +-20ppm.

From smart beacon reference source v1.0.1, the ble_stack_init function is initialized as below: This means that LFCLK accuracy has +-20ppm.

SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_XTAL_20_PPM, true);

But, smart beacon reference source v1.1.0, the LFCK accuacry is changed from 20 to 50ppm.

SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_XTAL_50_PPM, true);

I think that the LFCLK accuracy should be initialized with 20ppm. I want to know why the LFCLK accuracy is changed in the latest smart beacon reference source even though the hardware is not changed.

Thanks in advance

oceanide

[Locky]

Likely for greater timing error margin with Smart phones. Alot of todays smartphones don't have the most accurate LFCLKs. Pretty sure the iPhone 6 doesn't even properly follow the SIG's BLE timing