High eDRX current consumption on NRF9161_DK and disable the UICC interface during eDRX not working

[mnjLC]

Hello all,

We are taking our power measurements on NRF9161 DK board PCA10153 0.9.1. We are using NB-IoT for the LPWAN conection  We are supplying power to the board using the source meter mode on the NRFPPK2. To confirm that sim shut off is possible on our sim, we captured the AT+CRSM command output as below. 

> AT+CRSM=176,28589,0,0,0

+CRSM: 144,0,"01000803"

OK

According to this post, our sim is capable of sim shutodown. But still our sim is consuming 62uA of current during the eDRX cycles. Below is the screen shot of the sim current measurement of ~62uA.

Next, we tried taking current measurement for the e-DRX cycle. Cycle of 81.92s and PTW of 5.12s.

> AT%XDATAPRFL?

%XDATAPRFL: 0
> at+cedrxs=2,5,"0101"

OK
> at+cfun=1

OK

+CEDRXP: 5,"0101","0101","0011"
> at%xptw=5,"0001"

OK

+CEDRXP: 5,"0101","0101","0001"
> at#xsleep=2

OK

We see that the NRF9161 is consuming high current as compatred to NRF9160. Below is the screenshot of measured current consumption

Average measured current over a period of 10 minutes is 208uA seen in the image above.

With all the above information, we would like to report two bugs

1. Sim is not turning off during the e-DRX cycle

2. Floor current too high assuming sim is off during the edrx cycle. Currently with sim in ON state the floor current is 81uA
   
   

I am attaching the modem trace logs on this thread. Can someone from nordic look into this issue?

trace-2024-02-09T05-59-48.207Z.mtrace

[Didrik Rokhaug]

Hi,

I have started to look into this, but need some more time to do some tests on my side as well.

Could you also share the PPK traces as well?

Best regards,

Didrik

[mnjLC]

Hi,

Can you share a link, elaborating the process to collect ppk traces?

Thanks!

[mnjLC]

Hello Didrik Rokhaug
Attached are the requsted traces and corresponding PPK2 output
Thanks!
ppk-20240212T053013-sourcemode.ppktrace-2024-02-12T05-20-12.975Z-sourcemode.mtrace

[Didrik Rokhaug]

Thanks.

Nothing in the traces stands out to me immediately, so I've asked our modem team to have a look at the traces as well.

I'll get back to you when I have more to share.

[papatel]

Thank you Didrik.  Please make this a priority as this is gating production of a high volume wearable product.

SIM shutoff is a deal breaker for many battery powered applications and I hope it is already high priority for the Nordic firmware team to track extensively and check in regression testing.  Without this feature, e-DRX feature is often negated altogether.  Most MVNO and carrier provided SIMs support this feature now (at least from our investigations) so we consider it a core feature.

Some perhaps useful information:

• SIM shutoff is working as expected with the ALT1250 chipset on the same network/SIM/configuration.
• We also couldn't get SIM shutoff with this network/sim on the 9160 working either.  Although, the floor current was good after accounting for the SIM consumption (~4uA as documented).

Thank you!

-Patrick

[Didrik Rokhaug]

According to the modem team, "it looks like the SIM card indicates support for suspend in EF-UMPC, but it does not really support the SUSPEND UICC command APDU".

Which application are you using?

If your application uses GPIO pin interrupts, could you test the current consumption of an application that doesn't, such as the udp sample?

The upd sample can be configured to use eDRX by setting CONFIG_UDP_EDRX_ENABLE to 'y' in the prj.conf. You might also have to change which eDRX parameters are requested with CONFIG_LTE_EDRX_REQ_VALUE_NBIOT (the default is "1001") and CONFIG_LTE_PTW_VALUE_NBIOT.

Also, you might want to request a longer eDRX period. With %XDATAPRFL=0, the modem will try to suspend the SIM card if it goes to sleep for longer than 1 minute. However, the trace showed that despite the eDRX interval being 81.96s, the actual sleep interval wasn't always long enough.