Problems with nRF9151 - cannot connect over SWD - higher current consumption

[Walerij]

Hello,

we have produced 10 Boards with nRF9151. Unfortunately, 3 device shows a false behavior. We cannot connect over SWD an they have a larger power consumption (whole circuit) of 24mA instead of 5mA in case of the good one (measured without firmware). 

Also nReset is permanently low without connection though other components in the circuit. VDD has 3.3V but error message says "Low voltage 0"

Component NRF9151 reacts to external heat and external cold temperature in form of other error messages. 

Do you have an idea ? 

Error Messages: 

1:

[error] [ Client] - Encountered error -12: Command connect_to_emu_with_snr executed for 111 milliseconds with result -12
164210439  - UNKNOWN
[error] [ Worker] - Low voltage 0 detected in target device.

2:

[error] [ Client] - Encountered error -102: Command connect_to_emu_with_snr executed for 173 milliseconds with result -102
164210439  - UNKNOWN
[error] [ Worker] - An unknown error.

3: 

08:51:25.871

Failed "reading readback protection status for application core". Error: code: 1, description: Generic, message: Batch task protection-get failed, [Probe] Device error: Failed to configure Coresight: LOW_VOLTAGE

08:51:25.997

Error: Failed with exit code 1. One or more batch tasks failed: - [Probe] Device error: Failed to configure Coresight: LOW_VOLTAGE, code: Generic. Message: Batch task protection-get failed, [Probe] Device error: Failed to configure Coresight: LOW_VOLTAGE.

10:17:38.426

Error: Failed with exit code 1. Failed to device info one or more devices: * 164210439: [Probe] Device error: Failed to write DebugPort register 2: Unknown Error in J-Link DLL (error code =-1), code: Generic. Message: Operation device-info failed, [Probe] Device error: Failed to write DebugPort register 2: Unknown Error in J-Link DLL (error code =-1).

[Asbjørn]

Hello Walerijm

the situation you describe sounds like there's one or more shorts between pins/pads on the nRF9151 package on your PCB. I assume the numbers you are using (1-3) referes to the units with faults?

1: This error message we often see when the device to be programmed doesn't have the right voltage or that the reference on the SWD/JTAG interface isn't there. You have checked VDD all around this unit and they are all as epxtected? What about the VDD_REF on the JTAG, is that the level that you expect? 

2: This could be many issues again, the VDD is first thing to check, is it as expected on all? If VDD is stable and at the right level, could you check the SWD interface compared to GND to see if you might have a short betweeon one of them and GND?

3: Which commands are you using here? Which tools are you using to program it? Once again, the low voltage claim makes me initially want to check the VDD and SWD pins. 

I'm sorry not to be able to give you a better answer, but the errors you see matches the behaviour of units where there are shorts between some functional pin(s) and GND. Have you looked at the boards in microscope? Hows the assembly looking, any shorts that you can see around the edged of the package? 

Best regards

Asbjørn