Lora SX1278 sleep current high.

[anandspathak]

Dear jgromes,
i am using lora sx1278 with STM32G070KBT6 microcontroller on custom pcb with only lora connected. Using stm32 official core.
Successfully initialized and working on SPI_2. No issue on sending and receiving using interrupt mode. Everything is working good except I am facing strange issue when I put lora to sleep. In sleep mode current is 56 milli amp...
My test code is below for your kind reference:

#include "STM32LowPower.h"
#include <IWatchdog.h>
#include <SPI.h>
#include <RadioLib.h>
#include <HardwareSerial.h>

SPIClass SPI_2(PB7, PB6, PB8);
SX1278 radio = new Module(PB9, PB3, PA15, PB4, SPI_2);

HardwareSerial Serial1(PA10, PA9);

void setup() {
Serial1.begin(9600);
SPI_2.begin();
LowPower.begin();
Serial1.print(F("[SX1278] Initializing ... "));

int state = radio.begin();
if (state == RADIOLIB_ERR_NONE) {
Serial1.println(F("success!"));
} else {
Serial1.print(F("failed, code "));
Serial1.println(state);
while (true)
;
}

}

void loop() {

delay(2000);
radio.sleep();
LowPower.deepSleep(5000); // during this time i get 56 milli amp current.
}

i replaced lora module with new one...still same issue of high sleep current.

Earlier when i was using atmega328 the sleep current was under 10uA. But i migrated to STM32 I am facing this issue.

**Please note that I tested sleep current of bare microcontroller, its below 5uA... I think that i am using SPI2 while library is using SPI1 default so this might be some issue i am unaware of.

I need your kind suggestion in this matter. By the way i am using your encryption and decryption ECB mode methods, working good...

Thanks,
Regards,
Anand Pathak,
"BHARAT"

[HeadBoffin]

56mA is way high for a do-nothing sketch with a radio on idle, do you have a schematic to show what & how you've wired up?

[anandspathak]

Dear HeadBoffin,
As a last resort i went furthur and relaced the microcontroller itself with brand new one...the problem solved... the whole system now sits at 15uA in sleep sleep mode and its now good for me...it was microcontroller that went bad somehow....
Thanks for your reply,
Thanks,
Regards,
Anand Pathak,
"BHARAT"