RF design considerations for nRF9160

[Yaniv Reibenbach]

Hi,

I am developing a new design using your nRF9160(using LTE ONLY targeted for the US /FCC) + NRF52840 (using BLE ONLY)

I have noticed that in both the reference designs(THINY 91 & starter9160DK) have RF related components that are typically not mandatory for designs.

Kindly advise which of the following is required for the described design (keep in mind no GPS and no NFC are included):

- SAFFB2G45MA0F0A (BPF)

- QM12038

Regards,

Yaniv

[Hung Bui]

Hi Yaniv,

You are right, there are some extra component that's not in the reference design. 

1. SAFFB2G45MA0F0A : This is a SAW filter to attenuate signals from outside of the 2.4GHz ISM band. This is added to avoid the interference from the LTE activity of the NRF91 to the BLE radio. 

2. QM12038: This is a RF switch. It's needed on the Thingy91 because we use the small antenna from Fractus. This is to switch the antenna between bands. You can find the explanation in this video:  https://youtu.be/rjPd0sFuAyU?t=654