SLVSC56B September   2013  – November 2015 TPS54540-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Fixed Frequency PWM Control
      2. 7.3.2  Slope Compensation Output Current
      3. 7.3.3  Pulse-Skip Eco-mode
      4. 7.3.4  Low Dropout Operation and Bootstrap Voltage (BOOT)
      5. 7.3.5  Error Amplifier
      6. 7.3.6  Adjusting the Output Voltage
      7. 7.3.7  Enable and Adjusting Undervoltage Lockout
      8. 7.3.8  Internal Soft Start
      9. 7.3.9  Constant Switching Frequency and Timing Resistor (RT/CLK) Pin)
      10. 7.3.10 Synchronization to RT/CLK Pin
      11. 7.3.11 Maximum Switching Frequency
      12. 7.3.12 Accurate Current Limit
      13. 7.3.13 Overvoltage Protection
      14. 7.3.14 Thermal Shutdown
      15. 7.3.15 Small Signal Model for Loop Response
      16. 7.3.16 Simple Small Signal Model for Peak Current Mode Control
      17. 7.3.17 Small Signal Model for Frequency Compensation
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Buck Converter With 6-V to 42-V Input and 3.3-V at 5-A Output
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Selecting the Switching Frequency
          2. 8.2.1.2.2  Output Inductor Selection (LO)
          3. 8.2.1.2.3  Output Capacitor
          4. 8.2.1.2.4  Catch Diode
          5. 8.2.1.2.5  Input Capacitor
          6. 8.2.1.2.6  Bootstrap Capacitor Selection
          7. 8.2.1.2.7  Undervoltage Lockout Set Point
          8. 8.2.1.2.8  Output Voltage and Feedback Resistors Selection
          9. 8.2.1.2.9  Compensation
          10. 8.2.1.2.10 Power Dissipation Estimate
          11. 8.2.1.2.11 Safe Operating Area
          12. 8.2.1.2.12 Discontinuous Conduction Mode and Eco-mode Boundary
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Inverting Buck-Boost Topology for Positive Input to Negative Output
      3. 8.2.3 Split-Rail Power Supply
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Estimated Circuit Area
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DDA|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • Qualified for Automotive Applications
  • AEC-Q100 Qualified With the Following Results:
    • Device Temperature Grade 1: –40°C to 125°C Ambient Operating Temperature Range
    • Device HBM ESD Classification Level H1C
    • Device CDM ESD Classification Level C3B
  • High-Efficiency at Light Loads With Pulse-Skipping Eco-mode™
  • 92-mΩ High-Side MOSFET
  • 146-μA Operating Quiescent Current and 2-µA Shutdown Current
  • 100-kHz to 2.5-MHz Adjustable Switching Frequency
  • Synchronizes to External Clock
  • Low Dropout at Light Loads With Integrated BOOT Recharge FET
  • Adjustable UVLO Voltage and Hysteresis
  • 0.8-V 1% Internal Voltage Reference
  • 8-Pin HSOP PowerPAD™ Package
  • –40°C to 150°C TJ Operating Range
  • Supported by WEBENCH® Software Tool

2 Applications

  • Vehicle Accessories: GPS (See SLVA412), Entertainment, ADAS, eCall
  • USB-Dedicated Charging Ports and Battery Chargers (See SLVA464)
  • Industrial Automation and Motor Control
  • 12-V, 24-V, and 48-V Industrial, Automotive, and Communications Power Systems

    • SPACE

3 Description

The TPS54540-Q1 device is a 42-V, 5-A, step-down regulator with an integrated high-side MOSFET. The device survives load-dump pulses up to 65 V per ISO 7637. Current mode control provides simple external compensation and flexible component selection. A low-ripple pulse-skip mode reduces the no load supply current to 146 μA. Shutdown supply current is reduced to 2 μA when the enable pin is pulled low.

Undervoltage lockout is internally set at 4.3 V but can be increased using an external resistor divider at the enable pin. The output voltage start-up ramp is internally controlled to provide a controlled start-up and eliminate overshoot.

A wide adjustable frequency range allows either efficiency or external component size to be optimized. Output current is limited cycle-by-cycle. Frequency foldback and thermal shutdown protect internal and external components during an overload condition.

The TPS54540-Q1 is available in an 8-pin thermally-enhanced HSOP PowerPAD package.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
TPS54540-Q1 HSOP (8) 4.89 mm × 3.90 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

TPS54540-Q1 simple_sch_lvsbn0.gif

Efficiency vs Load Current

TPS54540-Q1 C024_SLVSBN0.png