SBOS844D May   2021  – August 2025 INA234

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Requirements (I2C)
    7. 5.7 Timing Diagram
    8. 5.8 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Integrated Analog-to-Digital Convertor (ADC)
      2. 6.3.2 Power Calculation
      3. 6.3.3 Low Bias Current
      4. 6.3.4 Low Voltage Supply and Wide Common-Mode Voltage Range
      5. 6.3.5 ALERT Pin
    4. 6.4 Device Functional Modes
      1. 6.4.1 Continuous Verses Triggered Operation
      2. 6.4.2 Device Shutdown
      3. 6.4.3 Power-On Reset
      4. 6.4.4 Averaging and Conversion Time Considerations
    5. 6.5 Programming
      1. 6.5.1 I2C Serial Interface
      2. 6.5.2 Writing to and Reading Through the I2C Serial Interface
      3. 6.5.3 High-Speed I2C Mode
      4. 6.5.4 General Call Reset
      5. 6.5.5 General Call Start Byte
      6. 6.5.6 SMBus Alert Response
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Device Measurement Range and Resolution
      2. 7.1.2 Current and Power Calculations
      3. 7.1.3 ADC Output Data Rate and Noise Performance
      4. 7.1.4 Filtering and Input Considerations
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Select the Shunt Resistor
        2. 7.2.2.2 Configure the Device
        3. 7.2.2.3 Program the Shunt Calibration Register
        4. 7.2.2.4 Set Desired Fault Thresholds
        5. 7.2.2.5 Calculate Returned Values
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Register Maps
    1. 8.1 Device Registers
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.1.1 Device Measurement Range and Resolution

The INA234 device supports two input ranges for the shunt voltage measurement. The supported full scale differential input across the IN+ and IN– pins can be either ±81.92mV or ±20.48mV depending on the ADCRANGE bit in the Configuration Register (0h) register. The range for the bus voltage measurement at the IN- pin is from 0V to 52.42V, but is limited by process ratings to the maximum operating voltage.

Table 7-4 provides a description of full scale voltage on shunt and bus voltage measurements, along with the associated resolution.

Table 7-1 ADC Full Scale Values
PARAMETERFULL SCALE VALUERESOLUTION
Shunt voltage±81.92mV (ADCRANGE = 0) 40 µV/LSB
±20.48mV (ADCRANGE = 1) 10 µV/LSB
Bus voltage0V to 52.4V (Limit usable range to recommended operating voltage)25.6 mV/LSB

The device shunt voltage and bus voltage measurements are read through the Shunt Voltage register (1h) and Bus Voltage register (2h), respectively. The digital output in shunt voltage and bus voltage registers is 16 bits with the last four bits reserved. The shunt voltage measurement can be positive or negative due to bidirectional currents in the system; therefore the data value in shunt voltage register can be positive or negative. The bus voltage register data value is always positive. The output data can be directly converted into voltage by multiplying the digital value by the respective resolution size.

Furthermore, the device provides the flexibility to report calculated current in Amperes, power in Watts, as described in Current and Power Calculations.