NRF9160 Temperature and Voltage Sampling Rate

[Thomas]

Hi,

The XTEMP, XPOFWARN and XVBATLOWLVL commands all allow you to set thresholds for temperature/voltage at which the modem sends a notification. When is the voltage/temperature sampled for these? Does it sample them periodically, if so how frequent;y? Does it perhaps use a voltage comparator instead to give instant feedback the moment temperature/voltage reaches a certain level?

Do the warnings get sent in AT+CFUN=0 or AT+CFUN=4 modes?

Kind regards,

Thomas

[helsing]

Hi Thomas,

Thank you for the question. I will take a look and get back to you tomorrow.

Best regards,

Håkon

[helsing]

Hi Thomas,

I have not been able to figure this out yet and I am checking with our experts. Please expect a delay. In the mean time, may I ask why you need to know this? Perhaps we could suggest another way to solve what you are trying to achieve?

Best regards,

Håkon Helsing

[Thomas]

Hi Håkon,

I wish to perform a health check for the battery (e.g temperature is too low, so the device should enter a low power state to avoid excess drain, or the battery voltage is too low to operate the modem reliably). If I can rely on the notifications from the modem then I will use that, otherwise I will need to sample the temperature and battery periodically.

You already have the commands for this purpose but since there is no documentation on how they work, its hard to know how to make use of them?

Kind regards,

Thomas

[helsing]

Thank you for the background info, I have forwarded this to our experts as well. Please expect a few days delay before we get back to you.

[helsing]

Hi Thomas,

Here are comments from our team:

For XVBATLOWLVL the voltage is the latest voltage measured automatically during wakeup or reception. The measured value is reliable.

XVBATLOWLVL and XTEMP: modem reads sensors periodically in connected mode, default period is 60 seconds. If temperature or voltage gets close to set threshold shorter period is used.

XPOFWARN based on voltage level detection without any delay. When this warning has happened once, it need to be enabled again by sending AT%XPOFWARN=1,<voltage>.

I hope this helps. Please let me know if you need any more information.

Best regards,

Håkon