SLVSD46A November   2017  – December 2021 TPS55160-Q1 , TPS55162-Q1 , TPS55165-Q1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Pin Configuration and 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 — External Components
    6. 7.6  Electrical Characteristics — Supply Voltage (VINP, VINL pins)
    7. 7.7  Electrical Characteristics — Reference Voltage (VOS_FB Pin) and Output Voltage (VOUT Pin)
    8. 7.8  Electrical Characteristics — Buck-Boost
    9. 7.9  Electrical Characteristics — Undervoltage and Overvoltage Lockout
    10. 7.10 Electrical Characteristics — IGN Wakeup
    11. 7.11 Electrical Characteristics — Logic Pins PS, IGN_PWRL, SS_EN
    12. 7.12 Electrical Characteristics – Overtemperature Protection
    13. 7.13 Electrical Characteristics – Power Good
    14. 7.14 Switching Characteristics — Reference Voltage (VOS_FB Pin) and Output Voltage (VOUT Pin)
    15. 7.15 Switching Characteristics — Buck-Boost
    16. 7.16 Switching Characteristics — Undervoltage and Overvoltage Lockout
    17. 7.17 Switching Characteristics — IGN Wakeup
    18. 7.18 Switching Characteristics — Logic Pins PS, IGN_PWRL, SS_EN
    19. 7.19 Switching Characteristics – Power Good
    20. 7.20 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Spread-Spectrum Feature
      2. 8.3.2 Overcurrent Protection
      3. 8.3.3 Overtemperature Protection
      4. 8.3.4 Undervoltage Lockout and Minimum Start-Up Voltage
      5. 8.3.5 Overvoltage Lockout
      6. 8.3.6 VOUT Overvoltage Protection
      7. 8.3.7 Power-Good Pin
    4. 8.4 Device Functional Modes
      1. 8.4.1 State Diagram
      2. 8.4.2 Modes of Operation
        1. 8.4.2.1 Normal Mode
        2. 8.4.2.2 Low-Power Mode
      3. 8.4.3 Power-Up and Power-Down Sequences
      4. 8.4.4 Soft-Start Feature
      5. 8.4.5 Pulldown Resistor on VOUT
      6. 8.4.6 Output Voltage Selection
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Application Circuits for Output Voltage Configurations
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Power-Circuit Selections: CIN, L, COUT
          1. 9.2.2.1.1 Inductor Current in Step-Down Mode
          2. 9.2.2.1.2 Inductor Current in Step-Up Mode
          3. 9.2.2.1.3 Inductor Current in Buck-Boost Overlap Mode
          4. 9.2.2.1.4 Inductor Peak Current
        2. 9.2.2.2 Control-Circuit Selections
          1. 9.2.2.2.1 Bootstrap Capacitors
          2. 9.2.2.2.2 VOUT-Sense Bypass Capacitor
          3. 9.2.2.2.3 VREG Bypass Capacitor
          4. 9.2.2.2.4 PG Pullup Resistor and Delay Time
      3. 9.2.3 Application Curves
  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 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
Inductor Current in Step-Down Mode

Use Equation 2 to calculate inductor peak-ripple current in the step-down, or buck, mode (Ipk_buck).

Equation 2. GUID-5A692A46-D7A9-4EB5-A819-7997FD2E684B-low.gif

where

  • VOUT is the output voltage.
  • L is the value of the inductor.
  • Dbuck is the duty cycle (refer to Equation 3).
  • fS is the switching frequency.
Equation 3. GUID-F3058B63-86FD-4448-9D1A-B14323528617-low.gif

The maximum peak-ripple current of the inductor (Ipk) occurs when the duty cycle is at the minimum value, specifically when the input voltage (VIN) is at the maximum value which yields the value shown in Equation 4.

Equation 4. GUID-A6210301-8F90-4C3F-A41B-5E8AFB5AE4D1-low.gif

Substitute the values for fS, L, and Dbuck, in Equation 2 to find the peak-ripple current as shown in Equation 5.

Equation 5. GUID-F544EBED-FE82-46B8-909A-E69E69A6C6E7-low.gif

The power dissipations can be determined by the RMS current of the inductor. Use Equation 6 to calculate the RMS current of the inductor in buck mode (Irms_buck).

Equation 6. GUID-3BE620EF-59AE-410D-828F-37237D483277-low.gif

Use Equation 7 to calculate the approximate power dissipation of the inductor in buck-mode (Ploss_L_buck).

Equation 7. GUID-01E6B0DA-E037-4F5F-9228-FDAA9ACEE247-low.gif