SLVSFT8F February   2023  – December 2023 TPS7H1111-SEP , TPS7H1111-SP

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options Table
  6. 5 Pin Configuration and Functions
  7. 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 Quality Conformance Inspection
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Bias Supply
      2. 8.3.2  Output Voltage Configuration
      3. 8.3.3  Output Voltage Configuration with a Voltage Source
      4. 8.3.4  Enable
      5. 8.3.5  Soft Start and Noise Reduction
      6. 8.3.6  Configurable Power Good
      7. 8.3.7  Current Limit
      8. 8.3.8  Stability
        1. 8.3.8.1 Output Capacitance
        2. 8.3.8.2 Compensation
      9. 8.3.9  Current Sharing
      10. 8.3.10 PSRR
      11. 8.3.11 Noise
      12. 8.3.12 Thermal Shutdown
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Application 1: Set Turn-On Threshold with EN
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Bias Supply
          2. 9.2.1.2.2 Output Voltage Configuration
          3. 9.2.1.2.3 Output Voltage Accuracy
          4. 9.2.1.2.4 Enable Threshold
          5. 9.2.1.2.5 Soft Start and Noise Reduction
          6. 9.2.1.2.6 Configurable Power Good
          7. 9.2.1.2.7 Current Limit
          8. 9.2.1.2.8 Output Capacitor and Ferrite Bead
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Application 2: Parallel Operation
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Current Sharing
        3. 9.2.2.3 Application Results
    3. 9.3 Capacitors Tested
    4. 9.4 TID Effects
    5. 9.5 Power Supply Recommendations
    6. 9.6 Layout
      1. 9.6.1 Layout Guidelines
      2. 9.6.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Third-Party Products Disclaimer
      2. 10.1.2 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
9.2.1.2.8 Output Capacitor and Ferrite Bead

In accordance with the Recommended Operating Conditions, 200 μF is selected for the output capacitance. Specifically, two 100 μF Tantalum AVX capacitors are utilized (see Section 9.3 for a list of capacitors TI has validated for use with the TPS7H1111-SP).

In this design a ferrite bead was also added for additional high frequency filtering. It is important to keep the OUTS connection before the ferrite bead (to keep the ferrite bead outside the TPS7H1111 control loop). If the ferrite bead was inside the control loop, the additional inductance may cause instability. In general, a ferrite bead is not required for good PSRR performance, but it was added here to determine its affects. Specifically, the KEMET Z1206C800APWST ferrite bead was selected for this design. While not utilized in this design, an additional 0.1 μF capacitor could be placed after the ferrite bead for additional filtering.