SLVS889C October   2008  – November 2014 TPS54140

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Simplified Schematic
  5. 5 Revision History
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 Handling Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Fixed Frequency PWM Control
      2. 8.3.2  Slope Compensation Output Current
      3. 8.3.3  Bootstrap Voltage (BOOT)
      4. 8.3.4  Low Dropout Operation
      5. 8.3.5  Error Amplifier
      6. 8.3.6  Voltage Reference
      7. 8.3.7  Adjusting the Output Voltage
      8. 8.3.8  Enable and Adjusting Undervoltage Lockout
      9. 8.3.9  Slow Start and Tracking Pin (SS/TR)
      10. 8.3.10 Overload-Recovery Circuit
      11. 8.3.11 Sequencing
      12. 8.3.12 Constant Switching Frequency and Timing Resistor (RT/CLK Pin)
      13. 8.3.13 Overcurrent Protection and Frequency Shift
      14. 8.3.14 Selecting the Switching Frequency
      15. 8.3.15 How to Interface to RT/CLK Pin
      16. 8.3.16 Power Good (PWRGD Pin)
      17. 8.3.17 Overvoltage Transient Protection
      18. 8.3.18 Thermal Shutdown
      19. 8.3.19 Small-Signal Model for Loop Response
      20. 8.3.20 Simple Small-Signal Model for Peak-Current Mode Control
      21. 8.3.21 Small-Signal Model for Frequency Compensation
    4. 8.4 Device Functional Modes
      1. 8.4.1 Pulse Skip Eco-mode
      2. 8.4.2 Operation With VIN < 3.5 V
      3. 8.4.3 Operation With EN Control
  9. 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  Selecting the Switching Frequency
        2. 9.2.2.2  Output Inductor Selection (LO)
        3. 9.2.2.3  Output Capacitor
        4. 9.2.2.4  Catch Diode
        5. 9.2.2.5  Input Capacitor
        6. 9.2.2.6  Slow-Start Capacitor
        7. 9.2.2.7  Bootstrap Capacitor Selection
        8. 9.2.2.8  Undervoltage-Lockout Set Point
        9. 9.2.2.9  Output Voltage and Feedback Resistors Selection
        10. 9.2.2.10 Compensation
        11. 9.2.2.11 Power Dissipation Estimate
      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 Third-Party Products Disclaimer
      2. 12.1.2 Development Support
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • 3.5- to 42-V Input Voltage Range
  • 200-mΩ High-Side MOSFET
  • High Efficiency at Light Loads with a Pulse Skipping Eco-mode™
  • 116-μA Operating Quiescent Current
  • 1.3-μA Shutdown Current
  • 100-kHz to 2.5-MHz Switching Frequency
  • Synchronizes to External Clock
  • Adjustable Slow Start and Sequencing
  • UV and OV Power-Good Output
  • Adjustable UVLO Voltage and Hysteresis
  • 0.8-V Internal Voltage Reference
  • MSOP10 Package With PowerPAD™
  • Supported by WEBENCH® Software Tool (www.TI.com/WEBENCH)

2 Applications

  • 12-V and 24-V Industrial and Commercial Low Power Systems
  • Aftermarket Auto Accessories: Video, GPS, Entertainment

3 Description

The TPS54140 device is a 42-V, 1.5-A, step-down regulator with an integrated high-side MOSFET. Current mode control provides simple external compensation and flexible component selection. A low-ripple pulse-skip mode reduces the no load, regulated output-supply current to 116 μA. Using the enable pin, the shutdown supply current is reduced to 1.3 μA.

Undervoltage lockout is internally set at 2.5 V, but can be increased using the enable pin. The output-voltage startup ramp is controlled by the slow-start pin that can also be configured for sequencing and tracking. An open-drain power-good signal indicates the output is within 94% to 107% of the nominal voltage.

A wide switching frequency range allows efficiency and external component size to be optimized. Frequency foldback and thermal shutdown protects the device during an overload condition.

The TPS54140 device is available in a 10-pin thermally enhanced MSOP PowerPAD package.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
TPS54140 MSOP (10) 3.00 mm × 3.00 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

4 Simplified Schematic

sim_sch_lvs795.gif

Efficiency vs Load Current

eff_lc_lvs795.gif