Current measurement for a Nordic Thingy 91 device

[Adeel]

Hi Dev Zone Team,

I had a question regarding the current measurement of Nordic Thingy 91. I am following the steps provided in the Thingy91 documentation. 

I have a Joulescope (https://www.joulescope.com/) for the current measurement and viewing. 

I have cut the SB3 Jumper and wish to connect the Vdd and GND pins. I have also deattached the battery.

I wanted to know the voltage to be applied at the VDD_nRF91 pin and if possible a connection picture.

I have attached the schematic that I was following for reference and also my module that I wish to measure.

. 

Thanks :).

[helsing]

Hi Adeel,

Sorry for the late reply. I have found the way to do this and will get back to you shortly.

Best Regards,

Håkon

[Adeel]

Hi Håkon,

Thanks for the reply. I managed to work around with it and got the connections done.

I needed to do this in order to check the idle power consumption when AT+CFUN=0 i.e: when modem is off.

I noticed that the current at the modem-off mode is 1.2 mA which is quite more than I anticipated.

Can you give me some tips on how could I try and reduce this current consumption at the modem off mode.  

Thanks :)

[helsing]

Hi Adeel,

Which application are you running? When it comes to current consumption it is probably also worth mentioning the Online Power Profiler for nRF91.

Here is a blog post on how to achieve and measure the lowest current consumption with PSM mode.

I will get back to you over the weekend.

Best Regards,

Håkon

[Adeel]

Hi Hakon,

I was running the asset tracker application. I noticed that modem off mode current is quite higher when (about 1.2 mA) for the Nordic thingy91 device. I can share you the screenshot on monday so that you can have a look. I will also try your method as suggested in the Online Power Profiler as i have a nRF9160DK with me.

Regards,

Adeel.

[helsing]

Hi Adeel,

Are you measuring the current consumed by the whole thingy, or are you interested in the current consumed by nrf91 itself?

Please see the notes on Low Power in the README.rst of the asset_tracker application(assuming you are on NCS v1.3.0). Using PSM or eDRX mode will help you save power.

I have updated my previous message with the link that was missing.

Best regards,

Håkon