Wireless Stick Lite Low Power Mode

[amir]

Hi All,

I recently got a Wireless Stick Lite board for prototyping a Lora end device. Previously was using a WiFi Lora 32 (v2).

The board does in general consume less power. But when tested the deep sleep mode in the provided in the examples (same code @hunter8801 used here WiFi LoRa 32(V2) deep sleep low power test) I get about 2.67 mA when the board is powered from a 3.7v 750mAh RCR123a battery. The description claims 35 microAmps in deep sleep mode.

Only changes I made to the example was disable the display in the Heltec.begin() method, since this board doesn’t have a display and I increased the sleep/active period to 30 seconds, so I have some time to read the values from my multimeter.
In active time, the board is drawing around 44mA.
Setting RTC peripherals to sleep also didn’t make much difference. Is there anything specific that needs to be configured besides running that test?

Amir.

[amir]

After some more changes I can get to about 1.5mA in deep sleep. But I don’t think the 0.35uA is achievable unless you can run some of the code in ULP processor and that isn’t trivial to do.
So at this point I don’t think any of the ESP32 are suitable as battery operated end device.

[Saber]

Hi
I don’t think there is any chip with a low power mode that can reach 0.35uA.

But we did get a sleep current of 30uA in the low-power test of Wireless Stick Lite.
Have you updated to the latest low-power example, or did you choose the right board?

[amir]

Hi,

Sorry, I meant to say 35uA. Could you provide a link to the latest version of the example? I believe I am using the latest one, I copied it directly from the repo here:

HelTecAutomation/Heltec_ESP32

I am not sure what in the example would be specific to the stick lite.

Amir.

[Saber]

Hi:
I have tested this example.
It works fine.
When using a 3.7V 1A lithium battery, the current is about 30uA.

Please check again if it is a development board selection error?