JAJSFB6D April   2018  – July 2022 INA180-Q1 , INA2180-Q1 , INA4180-Q1

PRODMIX  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Device Comparison
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Thermal Information
    6. 7.6 Electrical Characteristics
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 High Bandwidth and Slew Rate
      2. 8.3.2 Wide Input Common-Mode Voltage Range
      3. 8.3.3 Precise Low-Side Current Sensing
      4. 8.3.4 Rail-to-Rail Output Swing
    4. 8.4 Device Functional Modes
      1. 8.4.1 Normal Mode
      2. 8.4.2 Input Differential Overload
      3. 8.4.3 Shutdown Mode
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Basic Connections
      2. 9.1.2 RSENSE and Device Gain Selection
      3. 9.1.3 Signal Filtering
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Common-Mode Transients Greater Than 26 V
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Examples
  10. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 サポート・リソース
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
      1.      Mechanical, Packaging, and Orderable Information

8.4.3 Shutdown Mode

Although the INAx180-Q1 do not have a shutdown pin, the low power consumption of the device allows the output of a logic gate or transistor switch to power the INAx180-Q1. This gate or switch turns on and off the INAx180-Q1 power-supply quiescent current.

However, in current shunt monitoring applications, there is also a concern for how much current is drained from the shunt circuit in shutdown conditions. Evaluating this current drain involves considering the simplified schematic of the INAx180-Q1 in shutdown mode, as shown in Figure 8-6.

GUID-28576B80-9F80-4922-929E-F90EABE4A7BE-low.gifFigure 8-6 Basic Circuit to Shut Down the INxA180-Q1

There is typically more than 500 kΩ of impedance (from the combination of 500-kΩ feedback and
input gain set resistors) from each input of the INAx180-Q1 to the OUT pin and to the GND pin. The amount of current flowing through these pins depends on the voltage at the connection.

Regarding the 500-kΩ path to the output pin, the output stage of a disabled INAx180-Q1 does constitute a good path to ground. Consequently, this current is directly proportional to a shunt common-mode voltage present across a 500-kΩ resistor.

As a final note, as long as the shunt common-mode voltage is greater than VS when the device is powered up, there is an additional and well-matched 55-µA typical current that flows in each of the inputs. If less than VS, the common-mode input currents are negligible, and the only current effects are the result of the 500-kΩ resistors.