INA219 Current Sensor with an Arduino Uno

// INA219 Current Sensor on Arduino Uno: wiring and a free simulation at https://www.tinkered.ai/components/ina219-current-sensor/arduino-uno
#include <Arduino.h>
#include <Wire.h>
#include <Adafruit_INA219.h>

Adafruit_INA219 ina219;   // 0x40: the module's A0/A1 jumpers open

void setup() {
  Serial.begin(115200);
  if (!ina219.begin()) {
    Serial.println("INA219 not found: check VCC, SDA/SCL and its address jumpers");
    while (true) delay(10);
  }
  // begin() calibrates for 32 V / 2 A (0.1 mA steps); for loads under 400 mA:
  // ina219.setCalibration_16V_400mA();
}

void loop() {
  float shuntMv = ina219.getShuntVoltage_mV();
  float busV = ina219.getBusVoltage_V();     // VIN- against GND: the load's voltage
  float currentMa = ina219.getCurrent_mA();
  float powerMw = ina219.getPower_mW();
  float supplyV = busV + shuntMv / 1000.0;   // VIN+: the supply's voltage

  Serial.print("Load: ");
  Serial.print(busV, 3);
  Serial.print(" V  Supply: ");
  Serial.print(supplyV, 3);
  Serial.print(" V  Current: ");
  Serial.print(currentMa, 1);
  Serial.print(" mA  Power: ");
  Serial.print(powerMw, 0);
  Serial.println(" mW");
  delay(500);
}