JAJSLX7 March   2023 INA310A , INA310B

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Amplifier Input Common-Mode Signal
      2. 7.3.2  Input-Signal Bandwidth
      3. 7.3.3  Low Input Bias Current
      4. 7.3.4  Low VSENSE Operation
      5. 7.3.5  Wide Fixed Gain Output
      6. 7.3.6  Wide Supply Range
      7. 7.3.7  Integrated Comparator
      8. 7.3.8  RESET Function
      9. 7.3.9  Short Propagation Delay
      10. 7.3.10 Comparator Input Bias Current
    4. 7.4 Device Functional Modes
      1. 7.4.1 Basic Connections
        1. 7.4.1.1 Overcurrent Threshold Connection
      2. 7.4.2 High-Side Switch Overcurrent Shutdown
      3. 7.4.3 Bidirectional Overcurrent Comparator
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 RSENSE and Device Gain Selection
    2. 8.2 Typical Application
      1. 8.2.1 Current Sensing in a Solenoid Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Overload Recovery With Negative VSENSE
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Low-Side Switch Overcurrent Shutdown
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curve
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Power Supply Decoupling
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 サポート・リソース
    3. 9.3 Trademarks
    4. 9.4 静電気放電に関する注意事項
    5. 9.5 用語集
  10. 10Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8.2.1.2 Detailed Design Procedure

The INA310x is designed to measure current in a typical solenoid application. The INA310x measures current across the 50-mΩ shunt that is placed at the output of the half-bridge. The INA310x measures the differential voltage across the shunt resistor, and the signal is internally amplified with a gain of 50 V/V. The output of the INA310x is connected to the analog-to-digital converter (ADC) of an MCU to digitize the current measurements.

R2 is fixed as 10 kΩ to avoid loading of OUT as recommended in Overcurrent Threshold Connection. R1 is calculated as 69.15 kΩ using Equation 1.

1.9 A = 0.6 V × ( R 1 + 10 kΩ ) 10 kΩ × 50 × 50 mΩ

R1 (69.15 kΩ) and R2 (10 kΩ) divides down the output which is an input to the comparator. This sets the overcurrent alert threshold of 1.9 A.

Solenoid loads are highly inductive and are often prone to failure. Solenoids are often used for position control, precise fluid control, and fluid regulation. Measuring real-time current on the solenoid continuously can indicate premature failure of the solenoid, which can lead to a faulty control loop in the system. Measuring high-side current also indicates if there are any ground faults on the solenoid or the FETs that can be damaged in an application. The INA310x, with high bandwidth and slew rate, can be used to detect fast overcurrent conditions to prevent the solenoid damage from short-to-ground faults.