Here is a rough demo program that draws approx 1uA when idle.
Seeed XIAO nRF52840 (not sense).
LEDs a turned on after a couple of push button switches are polled in Setup after switch interrupts.
Program needs an expert to comment and tidy up.
Hi !
Thank you for your advice.
My project uses a bare nRF52840 chip (there is no spi flash on the board and there is no microphone and there is no sense module).
But the current in sleep mode is still 8 µA.
Here are a couple my of tests and current results following NRF52 simple code for shutdown:
// Basic_Shutdown_20230522_01.ino
// 3.2 volts on 3V3 to GND
// current 21.2 uA during Delay
// current 18.0 uA after Delay
//
void setup()
{
delay(10000);
NRF_POWER->SYSTEMOFF = 1;
}
void loop()
{
}
// Basic_Shutdown_20230522_02.ino
// 3.2 volts on 3V3 to GND
// current 4.4 uA during Delay.
// Current 1.1 uA after Delay
//
#include <bluefruit.h>
#include <Adafruit_FlashTransport.h>
//
void setup()
{
//
Adafruit_FlashTransport_QSPI flashTransport;
Bluefruit.begin();
flashTransport.begin();
flashTransport.runCommand(0xB9);
flashTransport.end();
//
delay(10000);
NRF_POWER->SYSTEMOFF = 1;
}
void loop()
{
}
Thank you very much!
I 'll check it tonight !
AdamM68, Gordy7 !
Thank you very much for your help !
Everything worked out, the current is less than 1 µA!
When I run this, I get 733.77uA during the delay and 731.69uA After. Any Idea what I might be missing? Nothing else is attached.
I am not familiar with the Data Logger you are using.
I used a DMM on the uA range connected between the 3.2v battery and the 3V3 terminal on the XIAO nRF.
I was careful to make sure that the USB connection to the XIAO was removed.
Some questions regarding your set up but not sure if these will help:
- You have applied 4.097V but Gordy7 only applied 3.2V
- Gordy7 applied the voltage across 3V3 and GND pins
The Xiao board can only accept voltage > 3.6V at the battery pins, if you apply 4.097V at 3V3 pin you will be stressing your board.
Has anyone checked this issue ? :
- how do You connect xiao for making measurements ?
Maybe there is an issue when You power the xiao board via different paths
1: USB port with 5v
2: battery port with 3,6 - 4,2 v
3: 3v3 pin