XIAO ESP32S3 deep sleep current higher than expected

Products & Technology XIAO
#1

Hello!
Recently I bought one Xiao Esp32C3, one Xiao Esp32S3 and one Xiao Esp32C6 to test them for the current consumption in deep sleep mode.
I was expecting for Esp32C3 not to be able to compete with the other two, so from the beginning I have removed the voltage regulator&battery charger ICs from the board. Now, my modified Xiao Esp32C3 consumes about 11uA while in deep sleep and supplied via 3v3 pin from Nordic Power Profiler Kit II.
Today I had some time to play with Xiao Esp32S3. After I removed the annoying charging LED, I did my measurements and I got a very unpleasant surprise. If I supply it on 3V3 pin, I measure about 34mA during active state and about 298uA during sleep. If I supply it on 5V pin, I measure again about 34mA while active and about 63uA during sleep. Active current is really fine, but the deep sleep current is way too high than I was expecting. I thought it should be less than 20uA. Xiao board is not connected to anything else, just voltage supply wires from PPK II.
My program is written in Arduino platform in Platform IO and is simple like this:

#include <Arduino.h>

#define TIME_TO_SLEEP  2        /* Time ESP32 will go to sleep (in seconds) */


void setup()
{
  delay(1000);
  esp_sleep_enable_timer_wakeup(TIME_TO_SLEEP * 1000000);
  esp_deep_sleep_start();
}

void loop()
{
}

Now, the main question: what should I do more in SW to get below 20uA during deep sleep?
My next step would be to apply the same “operation” like I did for Xiao ESP32C3: remove the metallic shield and get rid of voltage regulator and charging ICs. But I still hope there should be a solution just from software…

I would appreciate any suggestion that can help me to reduce the current consumption of Xiao ESP32S3 just from code.

Thank you!

#2

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This is my measurement setup.

#3

I made the same measurement and observed almost the same sleep current as the datasheet. The only difference in the setup is that I am applying 3.8V from ppk2 to the battery pad.
The link below is my post. For reference!
‘Comparison of Sleep Currents for XIAO ESP32C6, S3, and C3’

#4

Hi, thank you for your answer.
I did today the measurement as you did and I manage to get ~12uA in deep sleep while supplying 4.1V from PPK2 to battery pads.
I really wanted to use 5V pin because I don’t need to solder additional wires on the PCB to power the Xiao. I’m still wandering who’s causing the additional 50uA when powering on 5V pin compared to battery pads.
It would be nice if Seeed Studio would write directly in the wiki page that the smallest sleep current can be achieved only when powering from battery pads. It would save many hours of trial and error for people like me who want to use 5V pin or 3V3 pin.

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