NICLA Sense ME battery charging current

Official Hardware Nicla Family Nicla Sense ME
1

Hello everyone!
I would appreciate any help on this subject - i can read and write BQ25120A registers without a problem, but whatever value i write into Fast Charge Control Register it is allways charging with approx 15mA (measured with DMM)...
Did anyone manage to set higher current and how?
To be clear - i can write any value into Fast Charge Control Register and that value will be stored - checked by reading the register...
Lower values like 10mA also do not work...

Many thanks,

Josip

2

Hello again!
I have made a more precise measurement, charging current is in fact 11mA (do not believe it is important, but just in case...)
one of the codes i used to test this is :



#define BQ25120A_FAST_CHG_AFTER_BOOT 176 //charging current = 120mA
#define BQ25120A_ILIM_UVLO_CTRL_AFTER_BOOT 56 //BUVLO = 3V

#include "Nicla_System.h"


constexpr auto printInterval { 1000ul };
float voltage = -1.0f;
int x;



void setup(){
  Serial.begin(115200);
  

  for (const auto timeout = millis() + 2500; millis() < timeout && !Serial; delay(250));
  nicla::begin(); // Initialise library
  nicla::leds.begin(); // Start I2C connection to LED driver

  initBQ25120A();

  nicla::leds.setColor(blue);
}

void loop(){

  static auto updateTimestamp = millis();

  if (millis() - updateTimestamp >= printInterval) {
    updateTimestamp = millis();

    float currentVoltage = nicla::getCurrentBatteryVoltage();
    if(currentVoltage != voltage){
      voltage = currentVoltage;    
      Serial.print("\nVoltage: ");
      Serial.println(voltage);      
    } else {
      Serial.print(".");
    }

    auto operatingStatus = nicla::getOperatingStatus();

    switch(operatingStatus) {
      case OperatingStatus::Charging:
      nicla::leds.setColor(255,100,0); // Yellow
        break;
      case OperatingStatus::ChargingComplete:
        nicla::leds.setColor(green);
        
        // This will stop further charging until enableCharging() is called again.
        nicla::disableCharging();
        break;
      case OperatingStatus::Error:
        nicla::leds.setColor(red);
        break;
      case OperatingStatus::Ready:
        nicla::leds.setColor(blue);
        break;
      default:
        nicla::leds.setColor(off);
        break;
    }

  }
 
}




void initBQ25120A(){
  Serial.println("BQ25120A Register Map Values after BOOT...");
  printBQ25120ARegisterMap();
  
  setBQ25120ARegisterMapValues();
  Serial.println("BQ25120A Register Map Values after SETUP");
  printBQ25120ARegisterMap();
}


void setBQ25120ARegisterMapValues(){
  nicla::setBatteryNTCEnabled(false); 
  nicla::configureChargingSafetyTimer(ChargingSafetyTimerOption::ThreeHours);

  BQ25120A().writeByte(BQ25120A_ADDRESS, BQ25120A_ILIM_UVLO_CTRL, BQ25120A_ILIM_UVLO_CTRL_AFTER_BOOT); 
  BQ25120A().writeByte(BQ25120A_ADDRESS, BQ25120A_FAST_CHG, BQ25120A_FAST_CHG_AFTER_BOOT);   
}




void printBQ25120ARegisterMap(){
  uint8_t value = 0;
/*
  // Register Map
  #define BQ25120A_STATUS             0x00
  #define BQ25120A_FAULTS             0x01
  #define BQ25120A_TS_CONTROL         0x02
  #define BQ25120A_FAST_CHG           0x03
  #define BQ25120A_TERMINATION_CURR   0x04
  #define BQ25120A_BATTERY_CTRL       0x05
  #define BQ25120A_SYS_VOUT_CTRL      0x06
  #define BQ25120A_LDO_CTRL           0x07
  #define BQ25120A_PUSH_BUTT_CTRL     0x08
  #define BQ25120A_ILIM_UVLO_CTRL     0x09
  #define BQ25120A_BATT_MON           0x0A
  #define BQ25120A_VIN_DPM            0x0B
*/
  Serial.println("*********** BQ25120A Register Map Values ***********");
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_STATUS );
  Serial.print("BQ25120A_STATUS = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_FAULTS );
  Serial.print("BQ25120A_FAULTS = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_TS_CONTROL );
  Serial.print("BQ25120A_TS_CONTROL = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_FAST_CHG  );
  Serial.print("BQ25120A_FAST_CHG  = ");
  Serial.println(value);  
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_TERMINATION_CURR );
  Serial.print("BQ25120A_TERMINATION_CURR = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_BATTERY_CTRL );
  Serial.print("BQ25120A_BATTERY_CTRL = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_SYS_VOUT_CTRL );
  Serial.print("BQ25120A_SYS_VOUT_CTRL = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_LDO_CTRL );
  Serial.print("BQ25120A_LDO_CTRL = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_PUSH_BUTT_CTRL );
  Serial.print("BQ25120A_PUSH_BUTT_CTRL = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_ILIM_UVLO_CTRL );
  Serial.print("BQ25120A_ILIM_UVLO_CTRL = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_BATT_MON );
  Serial.print("BATT_MON = ");
  Serial.println(value);
  value = BQ25120A().readByte(BQ25120A_ADDRESS, BQ25120A_VIN_DPM );
  Serial.print("BQ25120A_VIN_DPM = ");
  Serial.println(value);  
  Serial.println("****************************************************");
  Serial.println("");
}