CubeCell Power Consumption

Hi,

using the sketch “LowPower_WakeUpByTimer.ino” example with CubeCell Board I meassure battery current:

  • 11,26mA during on Time
  • 0,83mA during sleep time

The current is meassured at SH1.25-2 battery interface. On https://heltec.org/project/htcc-ab01/ I read: Ultra low power design, 3.5uA in deep sleep;. What do I have to do to reduce current to max. 50uA or even better to 3.5uA?

On CubeCell Potential Issues Sleep Power and Settings Use I read about 20uA which would be OK for me. Is this not possible with wakeuptimer running?

After I have connected USB and diconnected the current changes from 19mA to 0,83mA during wakeup / sleep. Maybe something get initialized with usb connected? How can I disable this behavior?

I think there must have some problem during testing…

When you are testing, are you only powered by batteries? And how did you test it?

Did you connect an ammeter in series with the positive electrode of SH1.27-2?

I tested with another board (and same software). With this I get 24uA during sleep an 11mA during run mode which is OK.
There seems something wrong with the first board. Thanks for your help.

@memo5 Something I have just discovered thanks to a couple of other guys. When you are testing the low power mode make sure you unplug the USB and cycle the power. If you just unplug the USB the chip seems to stay active and consumes a lot more power.

Yes, you are right. I also had discovered this behavior. My current meassurements are all after a complete power cycle.