Precision Digital Current and Power Monitor using INA260

This is a digital-output, current, power, and voltage monitor with an I2C and SMBus™-compatible interface with an integrated precision shunt resistor. It enables high-accuracy current and power measurements and over-current detection at common-mode voltages that can vary from 0 V to 36 V, independent of the supply voltage. Module is a bidirectional, low- or high-side, current-shunt monitor that measures current flowing through the internal current-sensing resistor. The integration of the precision current-sensing resistor provides calibration-equivalent measurement accuracy with ultra-low temperature drift performance and ensures that an optimized Kelvin layout for the sensing resistor is always obtained.

The INA260 features up to 16 programmable addresses on the I2C-compatible interface. The digital interface allows programmable alert thresholds, analog-to-digital converter (ADC) conversion times, and averaging. To facilitate ease of use, an internal multiplier enables direct readouts of current in amperes and power in watts.

Features

• Operates From a 2.7-V to 5.5-V Power Supply
• Precision Integrated Shunt Resistor
• Current Sense Resistance: 2 mΩ
• Tolerance Equivalent to 0.1%
• 15-A Continuous From –40°C to +85°C
• 10 ppm/°C Temperature Coefficient (0°C to +125°C)
• Senses Bus Voltages From 0 V to 36 V
• High-Side or Low-Side Sensing
• Reports Current, Voltage, and Power
• High Accuracy:0.15% System Gain Error (Maximum),5-mA Offset (Maximum)
• Configurable Averaging Options
• 16 Programmable Addresses
• PCB Dimensions 36.20 x 23.34 mm
• 4 x 4MM Mounting Holes

Integrated Shunt Resistor

SDA SCL ALERT A0 A1 The INA260 features a precise, low-drift, current-sensing resistor to allow for precision measurements over the entire specified temperature range of–40°C to +125°C. The integrated current-sensing resistor ensures measurement stability over temperature as well as simplifying printed-circuit board (PCB) layout difficulties common in high precision current sensing measurements. The onboard current-sensing resistor is designed as a 4-wire (or Kelvin) connected resistor that enables accurate measurements through a force-sense connection. The Kelvin connections to the shunt are done internally eliminating many of the parasitic impedances commonly found in typical very-low sensing-resistor level measurements. Although the shunt resistor can be accessed through the IN+ and IN– pins, this resistor is not intended to be used as a stand-alone component. The INA260 is internally calibrated to ensure that the current sensing resistor and current-sensing amplifier are both precisely matched to one another. The INA260 has approximately 4.5 mΩ of total resistance between the IN+ and IN- pins. 2 mΩ of this total package resistance is a precisely-controlled resistance from the Kelvin-connected current-sensing resistor used by the internal analog to digital converter (ADC). The power dissipation requirements of the system and package are based on the total 4.5-mΩ package resistance. The heat dissipated across the package when current flows through the device ultimately determines the maximum current that can be safely handled by the package. The current consumption of the silicon is relatively low, leaving the total package resistance carrying the high load current as the primary contributor to the total power dissipation of the package. The maximum safe-operating current level is set to ensure that the heat dissipated across the package is limited so that no damage to the resistor or the package itself occurs or that the internal junction temperature of the silicon does not exceed a 150°C limit.