SLVSBX7B May   2013  – March 2017 TPS54540

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 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) Terminal)
      10. 7.3.10 Accurate Current Limit Operation and Maximum Switching Frequency
      11. 7.3.11 Synchronization to RT/CLK Terminal
      12. 7.3.12 Overvoltage Protection
      13. 7.3.13 Thermal Shutdown
      14. 7.3.14 Small Signal Model for Loop Response
      15. 7.3.15 Simple Small Signal Model for Peak Current Mode Control
      16. 7.3.16 Small Signal Model for Frequency Compensation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation with VIN = < 4.5 V (Minimum VIN)
      2. 7.4.2 Operation with EN Control
      3. 7.4.3 Alternate Power Supply Topologies
        1. 7.4.3.1 Inverting Power
        2. 7.4.3.2 Split Rail Power Supply
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  Custom Design with WEBENCH® Tools
        2. 8.2.2.2  Selecting the Switching Frequency
        3. 8.2.2.3  Output Inductor Selection (LO)
        4. 8.2.2.4  Output Capacitor
        5. 8.2.2.5  Catch Diode
        6. 8.2.2.6  Input Capacitor
        7. 8.2.2.7  Bootstrap Capacitor Selection
        8. 8.2.2.8  Undervoltage Lockout Set Point
        9. 8.2.2.9  Output Voltage and Feedback Resistors Selection
        10. 8.2.2.10 Minimum VIN
        11. 8.2.2.11 Compensation
        12. 8.2.2.12 Discontinuous Conduction Mode and Eco-mode Boundary
        13. 8.2.2.13 Power Dissipation Estimate
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Safe Operating Area
    2. 10.2 Layout Guidelines
    3. 10.3 Layout Example
      1. 10.3.1 Estimated Circuit Area
  11. 11Device and Documentation Support
    1. 11.1 Custom Design with WEBENCH® Tools
    2. 11.2 Receiving Notification of Documentation Updates
    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

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

1 Features

  • 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 Fixed 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-Terminal HSOP with PowerPAD™ Package
  • –40°C to 150°C TJ Operating Range
  • Create a Custom Design using the TPS54540 with the WEBENCH® Power Designer

2 Applications

  • Industrial Automation and Motor Control
  • Vehicle Accessories: GPS, Entertainment
  • USB Dedicated Charging Ports and Battery Chargers
  • 12 V and 24 V Industrial, Automotive and Communications Power Systems

3 Description

The TPS54540 is a 42 V, 5 A, step down regulator with an integrated high side MOSFET. The device survives load dump pulses up to 45V 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 the enable pin. The output voltage start up ramp is internally controlled to provide a controlled start up and eliminate overshoot.

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

The TPS54540 is available in an 8-terminal thermally enhanced HSOP PowerPAD™ package.

Device Information

PART NUMBER PACKAGE BODY SIZE
TPS54540 HSOP (8) 4,89mm x 3,9mm

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Simplified Schematic

TPS54540 simple_sch_lvsbx7.gif

Efficiency vs Load Current

TPS54540 frnt_page_eff_slvsbn0.gif