CC1350STK: Strange temperature and humidity values while running on battery power

Anastasiia M.

Part Number: CC1350STK

Hello,

my team is doing a university project, and we have just discovered, that if we unplug the USB cable and let the sensor tag run on its battery power, we get strange temperature and humidity values. For temperature, it is about -40 °C, for humidity about 10%. With cable, we get the right values. Only the humidity sensor is affected, pressure and lux are okay. We tried out multiple sensor tags and could replicate the problem. Do you have any idea what could be the reason for this behavior?

Cheers

over 2 years ago

0 TER over 2 years ago

TI__Guru**** 317180 points

Do you have a picture of your setup, including the USB cable connection?

0 Anastasiia M. over 2 years ago in reply to TER

Prodigy 10 points

I can't see how showing a picture of the setup could help answer our question. Sensor tag communicates with the launchpad over Sub-1Ghz, launchpad communicates with a computer over UART. The USB cable we meant was a cable connecting the sensor tag with a mounted debugger to the laptop.

0 TER over 2 years ago in reply to Anastasiia M.

TI__Guru**** 317180 points

I asked to see a picture since the CC1350STK doesn't have a USB connector and I wanted to see how you actually are using the SensorTag. With "mounted debugger", do you mean https://www.ti.com/tool/CC-DEVPACK-DEBUG?

Have you tried to disconnect the debugger when you use battery power? Have you verified the VDD level on the STK when running on battery power.

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

Sub-1 GHz

Sub-1 GHz forum

CC1350STK: Strange temperature and humidity values while running on battery power