SBOS969F October   2019  – January 2022 OPA2991 , OPA4991 , OPA991

PRODMIX  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  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 for Single Channel
    5. 6.5 Thermal Information for Dual Channel
    6. 6.6 Thermal Information for Quad Channel
    7. 6.7 Electrical Characteristics
    8. 6.8 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  Input Protection Circuitry
      2. 7.3.2  EMI Rejection
      3. 7.3.3  Thermal Protection
      4.      22
      5. 7.3.4  Capacitive Load and Stability
      6. 7.3.5  Common-Mode Voltage Range
      7. 7.3.6  Phase Reversal Protection
      8. 7.3.7  Electrical Overstress
      9. 7.3.8  Overload Recovery
      10. 7.3.9  Typical Specifications and Distributions
      11. 7.3.10 Packages With an Exposed Thermal Pad
      12. 7.3.11 Shutdown
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Low-Side Current Measurement
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 TINA-TI (Free Software Download)
        2. 11.1.1.2 TI Precision Designs
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.2 EMI Rejection

The OPAx991 uses integrated electromagnetic interference (EMI) filtering to reduce the effects of EMI from sources such as wireless communications and densely-populated boards with a mix of analog signal chain and digital components. EMI immunity can be improved with circuit design techniques; the OPAx991 benefits from these design improvements. Texas Instruments has developed the ability to accurately measure and quantify the immunity of an operational amplifier over a broad frequency spectrum extending from 10 MHz to 6 GHz. Figure 7-3 shows the results of this testing on the OPAx991. Table 7-1 shows the EMIRR IN+ values for the OPAx991 at particular frequencies commonly encountered in real-world applications. The EMI Rejection Ratio of Operational Amplifiers application report contains detailed information on the topic of EMIRR performance as it relates to op amps and is available for download from www.ti.com.

GUID-E6B96B47-F084-40BE-898D-7C30C4048C46-low.gifFigure 7-3 EMIRR Testing
Table 7-1 OPA991 EMIRR IN+ for Frequencies of Interest
FREQUENCYAPPLICATION OR ALLOCATIONEMIRR IN+
400 MHzMobile radio, mobile satellite, space operation, weather, radar, ultra-high frequency (UHF) applications73.2 dB
900 MHzGlobal system for mobile communications (GSM) applications, radio communication, navigation, GPS (to 1.6 GHz), GSM, aeronautical mobile, UHF applications82.5 dB
1.8 GHzGSM applications, mobile personal communications, broadband, satellite, L-band (1 GHz to 2 GHz)89.7 dB
2.4 GHz802.11b, 802.11g, 802.11n, Bluetooth®, mobile personal communications, industrial, scientific and medical (ISM) radio band, amateur radio and satellite, S-band (2 GHz to 4 GHz)93.9 dB
3.6 GHzRadiolocation, aero communication and navigation, satellite, mobile, S-band95.7 dB
5 GHz802.11a, 802.11n, aero communication and navigation, mobile communication, space and satellite operation, C-band (4 GHz to 8 GHz)98.0 dB