BLE advertising stoped un expectedly

[Dinkar]

Hello support,

We are developing a battery-operated sensor. For that, we are using nrf5340. Also, we made an enclosure for the sensor.

While developing we found that the BLE has stopped advertising.

Case 1: During further debugging found that when we keep the sensor open(without enclosure) it is advertising.

Case 2: If I keep the sensor in the enclosure and keep the charger connected to the sensor. After some time (approximately 2-3 hours) advertising is stopped. As the charger is connected to the sensor the sensor is minor heat(not extremely heat). I feel that due to heat, the sensor stopped advertising. Or is there any other reason for this issue? (This is only my observation there may be other reasons for causing the issue.).

Can anyone help me solve this advertising issue?

Appreciate your help.

Thanks,

Dinkar

[JONATHAN LL]

Case 1: During further debugging found that when we keep the sensor open(without enclosure) it is advertising.

Does it always work when it is outside of the enclosure? even for 2-3 hours?

Case 2: If I keep the sensor in the enclosure and keep the charger connected to the sensor. After some time (approximately 2-3 hours) advertising is stopped. As the charger is connected to the sensor the sensor is minor heat(not extremely heat). I feel that due to heat, the sensor stopped advertising. Or is there any other reason for this issue? (This is only my observation there may be other reasons for causing the issue.).

Does a reset solve the issue ? 
Have you tested to heat the device up while not in enclosure to see if same problem happens?



Can you share the schematic and maybe explain how the device is put together, what is the enclosure made out of? What other things are in the enclosure? what sensor? 

Regards,
Jonathan

[Dinkar]

Hello Jonathan,

Thanks for your reply.

1. Yes, it is continuously advertising whenever a sensor is outside the enclosure. I never observed the advertising stopped in this condition.

2. Yes if I did the hard reset of the MCU it will solve this issue.

3. As we are testing it in an open environment we never tested it to heat the device.

4. I attached the MCU and charging circuit portion of the schematic below.

The enclosure is made of plastic material. In the Enclosure, There are Sensor PCB, Battery(3.7V, 65mAh), and haptic motor(it is not continuously on. It is on for 10-15 secs in 1 hr approx.).

[JONATHAN LL]

You seem to be using a module, so I suspect that the HW is ok. 

How many units have you tested and do all have the same issues?

What SW are you running?

I would recommend that you try to and use SW that is from NCS 2.6 or later. 

Have you tested with some other SW also?  

Using a simple sample to test if the issue persists with samples as wall, that would then indicate a HW problem.

Regards,
Jonathan

[Dinkar]

As we are in the prototype phase we have limited hardware. We tested this thing in 3-4 hardware and observed most of the time.

We are collecting temperature, and barometer data from the 2c sensor and stream over ble. also store information in an external flash file as well.

We are using NCS version 2.6.1.

We have to keep the sensor on a charger. If we use the sample example charging may stop and heat may not generate. But let me check with an example. could you please suggest the best example to test this?