SBOS871 May   2019 INA190-Q1


  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Typical Application
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  6. Specifications
    1. 6.1      Absolute Maximum Ratings
    2. Table 1. ESD Ratings
    3. 6.2      Recommended Operating Conditions
    4. Table 2. Thermal Information
    5. 6.3      Electrical Characteristics
    6. 6.4      Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Precision Current Measurement
      2. 7.3.2 Low Input Bias Current
      3. 7.3.3 Low Quiescent Current
      4. 7.3.4 Bidirectional Current Monitoring
      5. 7.3.5 High-Side and Low-Side Current Sensing
      6. 7.3.6 High Common-Mode Rejection
      7. 7.3.7 Rail-to-Rail Output Swing
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Unidirectional Mode
      3. 7.4.3 Bidirectional Mode
      4. 7.4.4 Input Differential Overload
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Basic Connections
      2. 8.1.2 RSENSE and Device Gain Selection
      3. 8.1.3 Signal Conditioning
      4. 8.1.4 Common-Mode Voltage Transients
    2. 8.2 Typical Applications
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Common-Mode Voltage Transients

With a small amount of additional circuitry, the INA190-Q1 can be used in circuits subject to transients that exceed the absolute maximum voltage ratings. The most simple way to protect the inputs from negative transients is to add resistors in series to the IN– and IN+ pins. Use resistors that are 1 kΩ or less, and limit the current in the ESD structures to less than 5 mA. For example, using 1-kΩ resistors in series with the INA190-Q1 allows voltages as low as –5 V, while limiting the ESD current to less than 5 mA. If protection from high-voltage or more-negative, common-voltage transients is needed, use the circuits shown in Figure 36 and Figure 37. When implementing these circuits, use only Zener diodes or Zener-type transient absorbers (sometimes referred to as transzorbs); any other type of transient absorber has an unacceptable time delay. Start by adding a pair of resistors as a working impedance for the Zener diode, as shown in Figure 36. Keep these resistors as small as possible; most often, use around 100 Ω. Larger values can be used with an effect on gain that is discussed in the Signal Conditioning section. This circuit limits only short-term transients; therefore, many applications are satisfied with a 100-Ω resistor along with conventional Zener diodes of the lowest acceptable power rating. This combination uses the least amount of board space. These diodes can be found in packages as small as SOT-523 or SOD-523.

INA190-Q1 ina190-q1-protection-zener.gifFigure 36. Transient Protection Using Dual Zener Diodes

In the event that low-power Zener diodes do not have sufficient transient absorption capability, a higher-power transzorb must be used. The most package-efficient solution involves using a single transzorb and back-to-back diodes between the device inputs, as shown in Figure 37. The most space-efficient solutions are dual, series-connected diodes in a single SOT-523 or SOD-523 package. In either of the examples shown in Figure 36 and Figure 37, the total board area required by the INA190-Q1 with all protective components is less than that of an SO-8 package, and only slightly greater than that of an VSSOP-8 package.

INA190-Q1 ina190-q1-protection-tvs.gifFigure 37. Transient Protection Using a Single Transzorb and Input Clamps

For more information, see the Current Shunt Monitor With Transient Robustness reference design.