SLVSH48A May   2024  – September 2024 TPS7H1121-SP

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options
  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 Inspections
    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  Adjustable Output Voltage (Feedback Circuit)
      2. 8.3.2  Enable
      3. 8.3.3  Dropout Voltage VDO
      4. 8.3.4  Output Voltage Accuracy
      5. 8.3.5  Output Noise
      6. 8.3.6  Power Supply Rejection Ratio (PSRR)
      7. 8.3.7  Soft Start
      8. 8.3.8  Power Good (PG)
      9. 8.3.9  Stability
        1. 8.3.9.1 Stability
        2. 8.3.9.2 STAB Pin
      10. 8.3.10 Programmable Current Limit
      11. 8.3.11 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable / Disable
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Output Voltage Configuration
        2. 9.2.2.2 Output Voltage Accuracy
        3. 9.2.2.3 Enable Threshold
        4. 9.2.2.4 Soft Start Capacitor
        5. 9.2.2.5 Programmable Current Limit Resistor
        6. 9.2.2.6 Characterization of Overcurrent Events that Exceed Thermal Limits
        7. 9.2.2.7 Power Good Pull Up Resistor
        8. 9.2.2.8 Capacitors
          1. 9.2.2.8.1 Hybrid Output Capacitor Network
        9. 9.2.2.9 Frequency Compensation
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • HFT|22
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.6 Power Supply Rejection Ratio (PSRR)

The PSRR (power supply rejection ratio) of the TPS7H1121, is the amount of attenuation of the input noise at VIN, to the output, VOUT. PSRR is mathematically defined in Equation 5.

Equation 5. P S R R   = 20 × l o g 10 (   V I N ( A C ) V O U T ( A C ) )

The input noise is generally dominated by the switching ripple of an upstream converter. This noise occurs at the switching frequency and associated harmonics.

When using an external compensation network and the loop bandwidth is reduced, then the overall PSRR diminishes as well. Figure 6-22 illustrates the trade off in a typical application in which the applied compensation network has reduced the loop band-width, but improved system stability (RComp = 20kΩ, CComp = 1nF).