nRF9160 schematic design questions

RE: nRF9160 schematic design questions

Nishantt — Thu, 09 Mar 2023 10:44:32 GMT

Thank you for your support. I will raise one private ticket once our schematic design will be done.

RE: nRF9160 schematic design questions

ketiljo — Tue, 07 Mar 2023 13:25:59 GMT

1. This is to be able to use an external, active antenna. It it's not needed, you can replace all this with a single 39 pF cap:

4. Reset is normally high so you can pull it down with any transistor but not directly connected to 2.2 V.

RE: nRF9160 schematic design questions

Nishantt — Tue, 07 Mar 2023 05:41:03 GMT

Hello,

Thank you for your answers.

I have still some doubts in questions 1 & 4.

1. Why in nRF9160 DK schematic it placed MHF connector before the LNA circuit? Please find below image from DK.
Also please note that we are using BGS01SF011398 GPS patch antenna.

4. About the RESET circuit. It works on 2.2V and nrf52832 GPIO works on 3.3V. So I have to add one BJT (P/N : BC847CT-7-F ) for level shifting purposes or I can directly connect both (with the resistor in series as per recommendation)?

RE: nRF9160 schematic design questions

ketiljo — Mon, 06 Mar 2023 15:10:47 GMT

1. Using a LNA is highly recommended: https://infocenter.nordicsemi.com/topic/nwp_033/WP/nwp_033/nwp_033_gps.html

An antenna tuner is normally not needed but the antenna needs a pi or T match.

2. https://infocenter.nordicsemi.com/topic/nwp_037/WP/nwp_037/coex_if.html

3. VDD_GPIO can be applied and removed together with VDD.

4. https://infocenter.nordicsemi.com/topic/nwp_037/WP/nwp_037/nreset.html