Disabling the Electron red charging LED when not using the LiPo

Tutorials
6

I’m not sure why the LED is behaving that way for you. This is the circuit I tested with:

IMG_5936
IMG_59361600×1067 529 KB

  • The yellow wire is connected to D2 (sleep pin)
  • The orange wire is connected to D3 (wake pin)

Here’s the source I used:

#include "Particle.h"


void setCharging(bool enable);

const int SLEEP_PIN = D2;
const int WAKE_PIN = D3;

void setup() {
	Serial.begin();

	pinMode(SLEEP_PIN, INPUT_PULLUP);
	pinMode(WAKE_PIN, INPUT_PULLUP);

	setCharging(false);
}

void loop() {
	if (digitalRead(SLEEP_PIN) == LOW)  {
		System.sleep(WAKE_PIN, FALLING, 3600, SLEEP_NETWORK_STANDBY);
	}
}

void setCharging(bool enable) {

	PMIC pmic;

	// DisableCharging turns of charging. DisableBATFET completely disconnects the battery.
	if (enable) {
		pmic.enableCharging();
		pmic.enableBATFET();
	}
	else {
		pmic.disableCharging();
		pmic.disableBATFET();
	}

	// Disabling the watchdog is necessary, otherwise it will kick in and turn
	// charing at random times, even when sleeping.

	// This disables both the watchdog and the charge safety timer in
	// Charge Termination/Timer Control Register REG05
	// pmic.disableWatchdog() disables the watchdog, but doesn't disable the
	// charge safety timer, so the red LED will start blinking slowly after
	// 1 hour if you don't do both.
	byte DATA = pmic.readChargeTermRegister();

	if (enable) {
		DATA |= 0b00111000;
	}
	else {
		// 0b11001110 = disable watchdog
		// 0b11000110 = disable watchdog and charge safety timer
		DATA &= 0b11000110;
	}

	// This would be easier if pmic.writeRegister wasn't private (or disable
	// charge safety timer had an exposed method
	Wire3.beginTransmission(PMIC_ADDRESS);
	Wire3.write(CHARGE_TIMER_CONTROL_REGISTER);
	Wire3.write(DATA);
	Wire3.endTransmission(true);

}

I tested with 0.7.0.

After disconnecting the battery the red charging LED stayed off.

Connecting the yellow wire to GND caused the Electron to sleep; the red charging LED stayed off. After asleep I disconnected the yellow wire.

Connecting the orange wire to GND caused the Electron to wake up. I disconnected the orange wire.

I repeated a few cycles of this and it seemed to work fine.