nRF9160 reset issue

RE: nRF9160 reset issue

Stian Røed Hafskjold — Tue, 19 Jan 2021 12:59:26 GMT

Ok, sounds good. Yes, it's weird that it works when you pull it to 3.3V. I can't really explain that.

You can click on "more -> verify answer" on the answer that solved the issue! Thanks

RE: nRF9160 reset issue

Grigor — Tue, 19 Jan 2021 12:53:13 GMT

One more thing,

How I can change the ticket/discussion solved?

Thank you.

RE: nRF9160 reset issue

Grigor — Tue, 19 Jan 2021 12:52:05 GMT

Hi Stian,

Thank you for your reply.

Yeah, I think this part of nRF9160 has been damaged, but what is interesting, when we are connecting it directly to 3.3V we can program it without any issue:))

We are powering nRF52832 from 3.3V and will use S0D1 for resetting.

Thank you very much for your kindly support.

Regards,

Grigor

RE: nRF9160 reset issue

Stian Røed Hafskjold — Tue, 19 Jan 2021 12:40:51 GMT

Hi Grigor,

It sounds to me that the nRF9160 is damaged. Please note that the internal voltage in the nRF9160 is 2.2V and this is also the nRESET active voltage. By pulling it to 3.3V you might damage the circuitry inside the nRF9160.

What is the VDD voltage on the nRF52832? It should be within 2.2V +/- 0.3 V. For setting up the GPIO which is connected to nRESET use S0D1 (standard drive low, and disconnect high) It will pull the reset to 0 for resetting, and allow the internal pullup on 91 to pull it back up to 2.2V when active.

Stian

RE: nRF9160 reset issue

Grigor — Fri, 15 Jan 2021 14:11:41 GMT

Yeah,

Actually it's strange issue, because we have developed more than 7 boards and produced more than 50 samples and this is first time we are facing the issue.

The most strange thing, is, that the same voltage exist in nRESET pin on nRF9160-DK but it's working.

Also, 'not able to program' I men, that nRF connect software can't detect nRF9160 module for programming. But once we are connecting nRESET pin to 3.3V we can program the device and it's working without any problem.

For this design it's the first board but we had a lot of boards with similar schematic and all were working perfectly.

I would expect, that either this nRF9160 is faulty or this batch of nRF9160 have some errata.

Regards,

Grigor

RE: nRF9160 reset issue

Andreas — Fri, 15 Jan 2021 14:00:17 GMT

Hi,

This sounds a little strange, I will have to look into it and get back to you. Just for my reference, how many boards have you verified this occurrence in? Also, I assume that in the 'not able to program' state, the loaded FW is also not running (i.e. nRF9160 stuck in a reset state)?

Best regards,
Andreas

RE: nRF9160 reset issue

Grigor — Fri, 15 Jan 2021 10:08:28 GMT

Hi Andreas.

Currently we have disconnected nRESET from both pull-up resistor and nRF52832 GPIO.

Even in this case we can't program or detect nRF9160. We can only program and detect nRF9160 when connecting to 3.3V directly.

It's not working in case if we connecting to nRF52832 and driving this pin to "HIGH".

Thank you .

RE: nRF9160 reset issue

Andreas — Fri, 15 Jan 2021 09:32:09 GMT

Hi Grigor,

[quote user="Grigor"]We can program nRF9160 only when connecting nRESET pin to 3.3V directly.[/quote]

And the alternative to this, which is not working, is pulling nRESET high using a GPIO from nRF52840? What if you disconnect the GPIO in your nRF52840 code?

Best regards,
Andreas

RE: nRF9160 reset issue

Grigor — Thu, 14 Jan 2021 12:37:06 GMT

Hi Andreas,

Thank you for your promptly reply.

We have tried to program the nRF9160 without pull-up resistor and there where no any result.

We can program nRF9160 only when connecting nRESET pin to 3.3V directly.

Best regards,

Grigor

RE: nRF9160 reset issue

Andreas — Thu, 14 Jan 2021 12:15:45 GMT

Hi,

nRESET should not be pulled up externally.

Source: https://infocenter.nordicsemi.com/topic/ps_nrf9160/pin.html?cp=2_0_0_9_0_0#

Best regards,
Andreas