E-series pmic charging problems

Troubleshooting
1

Hi,
I’m having some troubles once again with the charging circuit of the E-Series module on my pcb.
What I’m seeing now after purchasing a new higher current supplying charger (Insignia 2.4A usb charger), I’m getting unpredictable charging rates. Im still using your PMIC settings that you provided shown below:

#include "Particle.h"
// Resets bq24195 charge controller
void writeRegister(uint8_t reg, uint8_t value);

void setup() {
   Serial.begin(9600);

   // REG00 Input Source Control Register
    writeRegister(0, 0b00110000);

    // REG01 Power-On Configuration Register
    writeRegister(1, 0b00011011);

    // REG02 Charge Current Control Register
    writeRegister(2, 0b01100000);

    // REG03 Pre-Charge/Termination Current Control Register
    writeRegister(3, 0b00010001);

    // REG04 Charge Voltage Control Register Format
    writeRegister(4, 0b10110010);

    // REG05 Charge Termination/Timer Control Register
    writeRegister(5, 0b10011010);

    // REG06 Thermal Regulation Control Register
    writeRegister(6, 0b00000011);

    // REG07 Misc Operation Control Register Format
    writeRegister(7, 0b01001011);

}

void loop() {
}

void writeRegister(uint8_t reg, uint8_t value) {
   // This would be easier if pmic.writeRegister wasn't private
   Wire3.beginTransmission(PMIC_ADDRESS);
   Wire3.write(reg);
   Wire3.write(value);
   Wire3.endTransmission(true);
}

I’m monitoring the current to the single cell lipo battery through a voltmeter and able to see the current change when it is charging. The most current I see going to the battery to charge it is when the E-series is set to sleep (I call this in my code: System.sleep(D4,FALLING):wink: and a few devices are turned off through mosfets on the pcb that are being supplied power through the particle’s 3V3 line. After this is called, the battery is getting about 340 mA which is ok but still not anywhere near what the charger would be able to supply and what the current settings are set to from your suggested register reset settings from my previous message in this post.
When the device comes out of sleep mode, the battery is no longer charging, but instead it is supplying current to the E-series module. This is with the high current capacity charger connected to the usb (pins 3,13,and 14 on the E-series). The rest of my circuit that the E-series module is part of pulls between 230 mA and 400 mA which is all being supplied through pin 9 of the module (3V3) which is well under the max that the 3V3 can supply (800mA). I’ve been referencing the datasheet for the BQ24195 IC but is there a good example for how to configure the PMIC using Particle’s built in functions?

The odd thing is that when I connect the usb instead to my PC, i can actually charge the battery when it is not in sleep mode. It is able to supply ~180 mA to the battery while also supplying power to the rest of my circuit. I don’t understand why the PC is able to supply more current than the actual high current charger!

Very confused…
Thanks,
Craig

2

See this recent thread for some ideas. That thread is for the Boron, which uses the same BQ24195 Chip.

3

Thanks for the suggestion Rftop.
Their issues are similar to mine and it did provide some insight.
I’ve also observed that when I put the E-series into sleep mode, it seems to check for DPDM connection and if not there, it does not charge. I have a usb connection where I can short the D+ and D- together and it keeps charging (>300mA) when sleeping. Otherwise, charging current is very low (less than 20 mA going to battery). Is there a setting to make this happen?
I’m very dissapointed with the lack of documentation on the PMIC.
I hope Particle is planning on implementing some documentation soon for this.