SLOS954A July   2018  – December 2018 INA253

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Typical Application
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  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 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Integrated Shunt Resistor
      2. 8.3.2 Short-Circuit Duration
      3. 8.3.3 Temperature Stability
      4. 8.3.4 Enhanced PWM Rejection Operation
      5. 8.3.5 Input Signal Bandwidth
    4. 8.4 Device Functional Modes
      1. 8.4.1 Adjusting the Output Midpoint With the Reference Pins
      2. 8.4.2 Reference Pin Connections for Unidirectional Current Measurements
      3. 8.4.3 Ground Referenced Output
      4. 8.4.4 Reference Pin Connections for Bidirectional Current Measurements
        1. 8.4.4.1 Output Set to External Reference Voltage
      5. 8.4.5 Output Set to Mid-Supply Voltage
      6. 8.4.6 Output Set to Mid-External Reference
      7. 8.4.7 Output Set Using Resistor Divide
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Input Filtering
    2. 9.2 Typical Applications
      1. 9.2.1 High-Side, High-Drive, Solenoid Current-Sense Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Speaker Enhancements and Diagnostics Using Current Sense Amplifier
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curve
      3. 9.2.3 Current Sensing for Remote I/Os in PLC
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Community Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Input Signal Bandwidth

The INA253 input signal, which represents the current being measured, is accurately measured with minimal disturbance from large ΔV/Δt common-mode transients as previously described. For PWM signals typically associated with motors, solenoids, and other switching applications, the current being monitored varies at a significantly slower rate than the faster PWM frequency.

The INA253 bandwidth is defined by the –3-dB bandwidth of the current-sense amplifier inside the device; see the Electrical Characteristics for more information. The device bandwidth provides fast throughput and fast response required for the rapid detection and processing of overcurrent events. Without the higher bandwidth, protection circuitry may not have adequate response time, and damage may occur to the monitored application or circuit.

Figure 32 shows the performance profile of the device over frequency. Harmonic distortion increases at the upper end of the amplifier bandwidth with no adverse change in detection of overcurrent events. However, increased distortion at the highest frequencies must be considered when the measured current bandwidth begins to approach the INA253 bandwidth.

INA253 D006_SBOS662.gifFigure 32. Amplifier Performance Over Frequency

For applications requiring distortion sensitive signals, Figure 32 provides information to show that there is an optimal frequency performance range for the amplifier. The full amplifier bandwidth is always available for fast overcurrent events at the same time that the lower-frequency signals are amplified at a low distortion level. The output signal accuracy is reduced for frequencies closer to the maximum bandwidth. Individual requirements determine the acceptable limits of distortion for high-frequency, current-sensing applications. Testing and evaluation in the end application or circuit are required to determine the acceptance criteria, and to validate the performance levels meet the system specifications.