SBOS576C May   2012  – September 2026 INA3221

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Basic ADC Functions
      2. 7.3.2 Alert Monitoring
        1. 7.3.2.1 Critical Alert
          1. 7.3.2.1.1 Summation Control Function
        2. 7.3.2.2 Warning Alert
        3. 7.3.2.3 Power-Valid Alert
        4. 7.3.2.4 Timing-Control Alert
        5. 7.3.2.5 Default Settings
      3. 7.3.3 Software Reset
    4. 7.4 Device Functional Modes
      1. 7.4.1 Averaging Function
      2. 7.4.2 Multiple Channel Monitoring
        1. 7.4.2.1 Channel Configuration
        2. 7.4.2.2 Averaging and Conversion-Time Considerations
      3. 7.4.3 Filtering and Input Considerations
    5. 7.5 Programming
      1. 7.5.1 Bus Overview
        1. 7.5.1.1 Serial Bus Address
        2. 7.5.1.2 Serial Interface
      2. 7.5.2 Writing To and Reading From the INA3221
        1. 7.5.2.1 High-Speed I2C Mode
      3. 7.5.3 SMBus Alert Response
  9. 8 Register Maps
    1. 8.1 Summary of Register Set
    2. 8.2 Register Descriptions
      1. 8.2.1  Configuration Register (address = 00h) [reset = 7127h]
      2. 8.2.2  Channel-1 Shunt-Voltage Register (address = 01h), [reset = 00h]
      3. 8.2.3  Channel-1 Bus-Voltage Register (address = 02h) [reset = 00h]
      4. 8.2.4  Channel-2 Shunt-Voltage Register (address = 03h) [reset = 00h]
      5. 8.2.5  Channel-2 Bus-Voltage Register (address = 04h) [reset = 00h]
      6. 8.2.6  Channel-3 Shunt-Voltage Register (address = 05h) [reset = 00h]
      7. 8.2.7  Channel-3 Bus-Voltage Register (address = 06h) [reset = 00h]
      8. 8.2.8  Channel-1 Critical-Alert Limit Register (address = 07h) [reset = 7FF8h]
      9. 8.2.9  Warning-Alert Channel-1 Limit Register (address = 08h) [reset = 7FF8h]
      10. 8.2.10 Channel-2 Critical-Alert Limit Register (address = 09h) [reset = 7FF8h]
      11. 8.2.11 Channel-2 Warning-Alert Limit Register (address = 0Ah) [reset = 7FF8h]
      12. 8.2.12 Channel-3 Critical-Alert Limit Register (address = 0Bh) [reset = 7FF8h]
      13. 8.2.13 Channel-3 Warning-Alert Limit Register (address = 0Ch) [reset = 7FF8h]
      14. 8.2.14 Shunt-Voltage Sum Register (address = 0Dh) [reset = 00h]
      15. 8.2.15 Shunt-Voltage Sum-Limit Register (address = 0Eh) [reset = 7FFEh]
      16. 8.2.16 Mask/Enable Register (address = 0Fh) [reset = 0002h]
      17. 8.2.17 Power-valid Upper-limit Register (address = 10h) [reset = 2710h]
      18. 8.2.18 Power-Valid Lower-Limit Register (address = 11h) [reset = 2328h]
      19. 8.2.19 Manufacturer ID Register (address = FEh) [reset = 5449h]
      20. 8.2.20 Die ID Register (address = FFh) [reset = 3220]
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

9.3 Power Supply Recommendations

The input circuitry of the device can accurately measure signals on common-mode voltages beyond the power supply voltage, VS. For example, the voltage applied to the VS power supply terminal can be 5V, whereas the load power-supply voltage being monitored (the common-mode voltage) on any one of the three channels can be as high as 26V. Note also that the device can withstand the full 0V to 26V range at the input terminals, regardless of whether the device has power applied or not. Place the required power-supply bypass capacitors as close as possible to the supply and ground terminals of the device to provide stability. A typical value for this supply bypass capacitor is 0.1μF. Applications with noisy or high-impedance power supplies can require additional decoupling capacitors to reject power-supply noise.