Thanks for the response @msfujino! I tested the S3 with three AA batteries at 4.5V connected to the battery pads and I got the nominal 14uA current. This solves my problem!
Some thoughts, partly for my own record:
- This only works via the battery pads. Connecting to the 5V pin brings on the battery charging LED, just like when I power the board via USB.
- I didn’t expect the voltage regulator’s consumption to jump like this due to low voltage. The regulators I used in solar low-power projects in the past did not exhibit this behavior.
- I didn’t check if the battery input officially supports 4.5V, but as it’s only 0.3V above the fully charged LiPo voltage of 4.2V, I’m ready to just wing it.
Also thanks for the additional notes! They are all duly noted.
I forgot to include in my original post but here is the platformio.ini file I was using:
[env:seeed_xiao_esp32s3]
platform = platformio/espressif32@^6.9.0
board = seeed_xiao_esp32s3
board_build.mcu = esp32s3
framework = arduino
build_flags =
-DARDUINO_USB_MODE=1
-DARDUINO_USB_CDC_ON_BOOT=1
;-DCONFIG_PM_ENABLE=1
;-DCONFIG_ESP_SLEEP_FLASH_LEAKAGE_WORKAROUND=1
;-DCONFIG_ESP_SLEEP_PSRAM_LEAKAGE_WORKAROUND=1
;-DCONFIG_ESP_SLEEP_POWER_DOWN_FLASH=1
monitor_speed = 115200
This may be interesting to the extent that:
- Removing the USB related build options did not change anything. The content was not related to the USB chip.
- The build options I commented out above were all things I tried that made no difference. They came up in other posts I found about ESP32 deep sleep current.