SLVSJB8A July   2025  – September 2025 TPS543021

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Fixed-Frequency PWM Control
      2. 6.3.2  Light Load Operation
      3. 6.3.3  Error Amplifier
      4. 6.3.4  Slope Compensation and Output Current
      5. 6.3.5  Enable and Adjusting Undervoltage Lockout
      6. 6.3.6  Safe Start-Up into Prebiased Outputs
      7. 6.3.7  Voltage Reference
      8. 6.3.8  Adjustable Output Voltage
      9. 6.3.9  Internal Soft Start
      10. 6.3.10 Bootstrap Voltage (BOOT)
      11. 6.3.11 Overcurrent Protection
        1. 6.3.11.1 High-Side MOSFET Overcurrent Protection
        2. 6.3.11.2 Low-Side MOSFET Overcurrent Protection
      12. 6.3.12 Spread Spectrum
      13. 6.3.13 Output Overvoltage Protection (OVP)
      14. 6.3.14 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 PFM Mode Operation
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 TPS543021 6V to 28V Input, 5V Output Converter
      2. 7.2.2 Design Requirements
      3. 7.2.3 Detailed Design Procedure
        1. 7.2.3.1 Custom Design With WEBENCH® Tools
        2. 7.2.3.2 Output Voltage Setpoint
        3. 7.2.3.3 Input Capacitor Selection
        4. 7.2.3.4 Bootstrap Capacitor Selection
        5. 7.2.3.5 Undervoltage Lockout Setpoint
        6. 7.2.3.6 Output Filter Components
          1. 7.2.3.6.1 Inductor Selection
          2. 7.2.3.6.2 Output Capacitor Selection
          3. 7.2.3.6.3 Feedforward Capacitor
      4. 7.2.4 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
      2. 8.1.2 Development Support
        1. 8.1.2.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

4 Pin Configuration and Functions

TPS543021 6-Pin SOT-563, DRL Package (Top View)Figure 4-1 6-Pin SOT-563, DRL Package (Top View)
Table 4-1 Pin Functions
PINTYPE(1)DESCRIPTION
NAMENO.
VIN 1 P Input voltage supply pin. The drain terminal of high-side FET. Connect to the input supply and input bypass capacitors CIN. Input bypass capacitors must be directly connected to this pin and GND.
SW2 P Switch node connection between high-side NFET and low-side NFET.
GND3 G Ground pin. Source terminal of low-side power NFET as well as the ground terminal for controller circuit. The path to CIN must be as short as possible.
BOOT 4 P Supply input for the high-side NFET gate drive circuit. Connect a high quality 0.1μF capacitor between BOOT and SW pins.
EN 5 A This pin is the enable pin. Float the EN pin to enable. Precision enable input allows an adjustable UVLO by an external resistor divider.
FB 6 A Converter feedback input. Connect to output voltage with feedback resistor divider. Never short this terminal to ground during operation.
(1) A = Analog, P = Power, G = Ground