nrf54 high power consumption after NFC tap

We are running a nrf54l15 board that uses an NFC T2T tag to encode a URI to open an application. We have noticed that sometimes, the current stays higher (~200 uA) after the NFC tap is complete and we receive the NFC_T2T_EVENT_FIELD_OFF event and does not drop back to what is was before the NFC tap. 

I have reproduced this on the nrf54l15dk running the modified record launch app (attached) from the v3.0.1 SDK. The only change I made was to ensure the device will enter a low power state by stopping the shell. I observe the following when running this application on the nrf54l15dk (the released DK, not the preview):

1. After boot, the application enables nfc and sits in a low power state ~10 uA. 

2. After an NFC tap, the current will spike and then return to this low power state of ~10 uA. (see nfc_tap_good.png)

3. Sometimes, after the NFC tap, the device does not return to the low power state and will sit in the high current state of ~200+ uA. This high current state does not go away. (See nfc_tap_high_current.png) 

4. If I tap the device again, I do sometimes see the power drop back down to 10 uA after the NFC_T2T_EVENT_FIELD_OFF event but other times it does not. 

In my testing, usually with an iPhone tap, this high power state would not occur, but I could reproduce it occasionally. However with a USB NFC reader (ACR122U), this seemed to happen much more frequently (around 75%) of the time. 

Are there any known issues that could cause this? 

3005.record_launch_app.zip

Parents
  • Hello,

    It looks like the HFCLOCK doesn't get turned off properly. I am sorry for the delayed response, but we have had some public Holidays here in Norway, so we have a bit of a backlog.

    I believe I have seen something similar to this before (although not on the nRF54L15. Let me try to dig a bit, and run some tests tomorrow. 

    By the way, what NCS version are you using to replicate this issue? NCS v3.0.x?

    Best regards,

    Edvin

Reply
  • Hello,

    It looks like the HFCLOCK doesn't get turned off properly. I am sorry for the delayed response, but we have had some public Holidays here in Norway, so we have a bit of a backlog.

    I believe I have seen something similar to this before (although not on the nRF54L15. Let me try to dig a bit, and run some tests tomorrow. 

    By the way, what NCS version are you using to replicate this issue? NCS v3.0.x?

    Best regards,

    Edvin

Children
Related