SNVS983A April   2024  – August 2024 TPS7H4011-SP

PRODMIX  

  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  VIN and Power VIN Pins (VIN and PVIN)
      2. 8.3.2  Voltage Reference
      3. 8.3.3  Remote Sensing and Setting VOUT
        1. 8.3.3.1 Minimum Output Voltage
        2. 8.3.3.2 Maximum Output Voltage
      4. 8.3.4  Enable
      5. 8.3.5  Fault Input (FAULT)
      6. 8.3.6  Power Good (PWRGD)
      7. 8.3.7  Adjustable Switching Frequency and Synchronization
        1. 8.3.7.1 Internal Clock Mode
        2. 8.3.7.2 External Clock Mode
        3. 8.3.7.3 Primary-Secondary Synchronization
      8. 8.3.8  Turn-On Behavior
        1. 8.3.8.1 Soft-Start (SS_TR)
        2. 8.3.8.2 Safe Start-Up Into Prebiased Outputs
        3. 8.3.8.3 Tracking and Sequencing
      9. 8.3.9  Protection Modes
        1. 8.3.9.1 Overcurrent Protection
          1. 8.3.9.1.1 High-Side 1 Overcurrent Protection (HS1)
          2. 8.3.9.1.2 High-Side 2 Overcurrent Protection (HS2)
          3. 8.3.9.1.3 COMP Shutdown
          4. 8.3.9.1.4 Low-Side Overcurrent Sinking Protection
        2. 8.3.9.2 Output Overvoltage Protection (OVP)
        3. 8.3.9.3 Thermal Shutdown
      10. 8.3.10 Error Amplifier and Loop Response
        1. 8.3.10.1 Error Amplifier
        2. 8.3.10.2 Power Stage Transconductance
        3. 8.3.10.3 Slope Compensation
        4. 8.3.10.4 Frequency Compensation
    4. 8.4 Device Functional Modes
  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  Operating Frequency
        2. 9.2.2.2  Output Inductor Selection
        3. 9.2.2.3  Output Capacitor Selection
        4. 9.2.2.4  Input Capacitor Selection
        5. 9.2.2.5  Soft-Start Capacitor Selection
        6. 9.2.2.6  Rising VIN Set Point (Configurable UVLO)
        7. 9.2.2.7  Output Voltage Feedback Resistor Selection
        8. 9.2.2.8  Output Voltage Accuracy
        9. 9.2.2.9  Slope Compensation Requirements
        10. 9.2.2.10 Compensation Component Selection
        11. 9.2.2.11 Schottky Diode
      3. 9.2.3 Application Curve
      4. 9.2.4 Parallel Operation Compensation
      5. 9.2.5 Inverting Buck-Boost
    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 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
    1. 12.1 Mechanical Data

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • HLB|30
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.2.5 Soft-Start Capacitor Selection

The soft-start capacitor CSS, determines the amount of time it takes for the output voltage to reach its nominal programmed value during power up. This is useful if a load requires a controlled voltage slew rate. This is also used if the output capacitance is large (as is typical with space grade buck converters), which would require a large amount of current to quickly charge the capacitor to the output voltage level. The large currents necessary to charge the capacitor may make the TPS7H4011 reach the current limit, draw excessive current from the input power supply, or cause the input voltage rail to sag. Limiting the output voltage slew rate solves these problems. The soft-start capacitor value can be calculated using Equation 7.

A reasonable soft start time for many space grade buck regulators is 5.8ms, which results in a CSS capacitor of 22nF.