SBOSA81D may   2021  – august 2023 INA236

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  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 Timing Requirements (I2C)
    7. 6.7 Timing Diagram
    8. 6.8 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 Integrated Analog-to-Digital Convertor (ADC)
      2. 7.3.2 Power Calculation
      3. 7.3.3 Low Bias Current
      4. 7.3.4 Low Voltage Supply and Wide Common-Mode Voltage Range
      5. 7.3.5 ALERT Pin
    4. 7.4 Device Functional Modes
      1. 7.4.1 Continuous Verses Triggered Operation
      2. 7.4.2 Device Shutdown
      3. 7.4.3 Power-On Reset
      4. 7.4.4 Averaging and Conversion Time Considerations
    5. 7.5 Programming
      1. 7.5.1 I2C Serial Interface
      2. 7.5.2 Writing to and Reading Through the I2C Serial Interface
      3. 7.5.3 High-Speed I2C Mode
      4. 7.5.4 General Call Reset
      5. 7.5.5 General Call Start Byte
      6. 7.5.6 SMBus Alert Response
    6. 7.6 Register Maps
      1. 7.6.1 Device Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Device Measurement Range and Resolution
      2. 8.1.2 Current and Power Calculations
      3. 8.1.3 ADC Output Data Rate and Noise Performance
      4. 8.1.4 Filtering and Input Considerations
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Select the Shunt Resistor
        2. 8.2.2.2 Configure the Device
        3. 8.2.2.3 Program the Shunt Calibration Register
        4. 8.2.2.4 Set Desired Fault Thresholds
        5. 8.2.2.5 Calculate Returned Values
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  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. 10Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DDF|8
  • YBJ|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.4.4 Averaging and Conversion Time Considerations

The INA236 has programmable conversion times for both the shunt voltage and bus voltage measurements. The conversion times for these measurements can be selected from as fast as 140 μs to as long as 8.244 ms. The conversion time settings, along with the programmable averaging mode, allow the INA236 to be configured to optimize the available timing requirements in a given application. For example, if a system requires that data be read every 5 ms, the INA236 can be configured with the conversion times set to 588 μs and the averaging mode set to 4. This configuration results in the data updating approximately every 4.7 ms. The INA236 can also be configured with a different conversion time setting for the shunt and bus voltage measurements. This type of approach is common in applications where the bus voltage tends to be relatively stable. This situation allows for the time spent measuring the bus voltage to be reduced relative to the shunt voltage measurement. The shunt voltage conversion time can be set to 4.156 ms with the bus voltage conversion time set to 588 μs, and the averaging mode set to 1. This configuration also results in data updating approximately every 4.7 ms.

There are trade-offs associated with the conversion time settings and the averaging mode used. The averaging feature can significantly improve the measurement accuracy by effectively filtering the signal. This approach allows the INA236 to reduce noise in the measurement that may be caused by noise coupling into the signal. A greater number of averages enables the INA236 to be more effective in reducing the noise component of the measurement.

The conversion times selected can also have an effect on the measurement accuracy. Figure 7-2 shows multiple conversion times to illustrate the effect of noise on the measurement. To achieve the highest accuracy measurement possible, use a combination of the longest allowable conversion times and highest number of averages, based on the timing requirements of the system.

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Figure 7-2 Noise vs Conversion Time