Overview

The INA260 is a 16-bit precision digital current, voltage, and power monitor manufactured by Texas Instruments. Unlike traditional power monitor ICs (such as the INA219 or INA226) that require external discrete sense resistors, the INA260 features a factory-calibrated, integrated 2 mΩ2\ \text{m}\Omega precision shunt resistor directly inside its 16-pin TSSOP package.

Capable of measuring continuous bidirectional currents up to ±15 A\pm 15\text{ A} (and peak currents up to ±36 A\pm 36\text{ A}) across bus voltages from 0 V to 36 V, the INA260 eliminates trace resistance errors, component selection math, and thermal calibration drift. It is widely used in Adafruit STEMMA QT modules, robot motor power tracking, and USB-C power delivery monitoring.

Quick reference

Operating voltage (VCC)2.7 V to 5.5 V DC
Bus voltage range (VBUS)0 V to 36 V DC
Continuous current rating±15 A\pm 15\text{ A} continuous (±36 A\pm 36\text{ A} peak)
Integrated shunt resistance2.0 mΩ±0.1%2.0\ \text{m}\Omega \pm 0.1\%
Resolution & LSB16-bit ADC (1.25 mA/LSB1.25\text{ mA/LSB} Current, 1.25 mV/LSB1.25\text{ mV/LSB} Voltage, 10 mW/LSB10\text{ mW/LSB} Power)
InterfaceI2CI^2C (Fast Mode up to 400 kHz, High-Speed up to 3.4 MHz)
Default I2CI^2C address0x40 (A0,A1→GNDA_0, A_1 \to \text{GND})
Operating current310 μA310\ \mu\text{A} active / 2 μA2\ \mu\text{A} power-down

Pinout & High-Current Terminal Block

Breakout board screw terminal & 6-pin logic header:

PinNameTypeDescription
1VCCPowerLogic power supply (+2.7 V to +5.5 V DC)
2GNDPowerGround reference (0 V)
3SCLDigital InputI2CI^2C Serial Clock
4SDADigital Input / OutputI2CI^2C Serial Data
5ALERTDigital OutputProgrammable alert / over-current interrupt output
6VBUSAnalog InputBus voltage sense pin (0 to 36V DC)
Screw 1IN+ / V+Heavy Current InputPositive current input terminal (connect to supply +)
Screw 2IN- / V-Heavy Current OutputNegative current output terminal (connect to load +)

Specifications

ParameterSymbolMinTypMaxUnitConditions
Supply VoltageVCCV_{CC}2.73.3 / 5.05.5VDC
Bus Voltage RangeVBUSV_{BUS}0—36.0VIndependent of VCCV_{CC}
Continuous CurrentICONTI_{CONT}-15.0—+15.0ATA≤85∘CT_A \le 85^\circ\text{C} continuous
Peak CurrentIPEAKI_{PEAK}-36.0—+36.0Atpulse<1 sect_{pulse} < 1\text{ sec}
Shunt ResistanceRshuntR_{shunt}1.9982.02.002mΩInternal silicon shunt
Shunt Thermal DriftTCshuntTC_{shunt}—10—ppm/°CLow thermal drift
Bus Voltage AccuracyEbusE_{bus}-0.1%±0.05%\pm 0.05\%+0.1%—Full scale
Current AccuracyEcurrE_{curr}-0.5%±0.15%\pm 0.15\%+0.5%—Full scale

Direct Reading Fixed Scales (No Math Required!)

Because the 2 mΩ2\ \text{m}\Omega internal shunt is factory-calibrated inside the IC, no custom calibration registers need to be calculated:

  • Current Register (0x01): 1.25 mA1.25\text{ mA} per LSB.

Current (A)=Raw Current Code×0.00125\text{Current (A)} = \text{Raw Current Code} \times 0.00125

  • Bus Voltage Register (0x02): 1.25 mV1.25\text{ mV} per LSB.

Bus Voltage (V)=Raw Bus Voltage Code×0.00125\text{Bus Voltage (V)} = \text{Raw Bus Voltage Code} \times 0.00125

  • Power Register (0x03): 10 mW10\text{ mW} per LSB.

Power (W)=Raw Power Code×0.010\text{Power (W)} = \text{Raw Power Code} \times 0.010

Wiring

INA260 Pin→Arduino / MCULoad / Power CircuitNotes
Screw Terminal V+—Power Supply Positive (+)High-current path
Screw Terminal V-—Load Positive Input (+)High-current path
VCC3.3V / 5V—Logic supply
GNDGNDPower Supply Ground (-)Shared common ground
SCLA5 / GPIO 22—I2CI^2C Clock
SDAA4 / GPIO 21—I2CI^2C Data

Example (Adafruit_INA260 Library)

cpp
#include <Wire.h>
#include <Adafruit_INA260.h>

Adafruit_INA260 ina260 = Adafruit_INA260();

void setup() {
  Serial.begin(115200);
  while (!Serial) delay(10);

  Serial.println("Adafruit INA260 Test");

  if (!ina260.begin()) {
    Serial.println("Couldn't find INA260 chip! Check wiring.");
    while (1);
  }
  Serial.println("Found INA260 chip");
}

void loop() {
  Serial.print("Current: "); Serial.print(ina260.readCurrent()); Serial.println(" mA");
  Serial.print("Bus Voltage: "); Serial.print(ina260.readBusVoltage()); Serial.println(" mV");
  Serial.print("Power: "); Serial.print(ina260.readPower()); Serial.println(" mW");
  Serial.println();

  delay(1000);
}

Common mistakes

  • Attempting to measure >15 A>15\text{ A} continuous without heatsinking: Continuous currents above 15 A15\text{ A} generate significant thermal dissipation (P=I2R=152×0.002=0.45 WP = I^2 R = 15^2 \times 0.002 = 0.45\text{ W}) inside the 16-pin TSSOP package. Ensure heavy copper PCB trace pours or external heatsinking for high-current loads.
  • Floating VBUS pin: If VBUS is left unconnected, voltage and power registers read 0. Connect VBUS to V+ to monitor bus voltage.

Notes

  • INA260 vs INA226: INA260 includes an integrated 2 mΩ2\ \text{m}\Omega 15 A15\text{ A} shunt; INA226 requires an external discrete shunt resistor.

Assets & downloads