SLVS500D DECEMBER   2003  – June 2019 TPS54110

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
  4. 4 Revision History
  5. 5 Device Information
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 Recommended Operating Conditions
    3. 7.3 Thermal Information
    4. 7.4 Electrical Characteristics
    5. 7.5 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 VBIAS Regulator (VBIAS)
      2. 8.3.2 Voltage Reference
      3. 8.3.3 Oscillator and PWM Ramp
      4. 8.3.4 Error Amplifier
      5. 8.3.5 PWM Control
      6. 8.3.6 Dead-Time Control and MOSFET Drivers
      7. 8.3.7 Overcurrent Protection
      8. 8.3.8 Thermal Shutdown
      9. 8.3.9 Power Good (PWRDG)
    4. 8.4 Undervoltage Lockout (UVLO)
    5. 8.5 Slow-Start/Enable (SS/ENA)
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Typical TPS54110 Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Switching Frequency
          2. 9.2.1.2.2 Input Capacitors
          3. 9.2.1.2.3 Output Filter Components
            1. 9.2.1.2.3.1 Inductor Selection
            2. 9.2.1.2.3.2 Capacitor Selection
          4. 9.2.1.2.4 Compensation Components
          5. 9.2.1.2.5 Bias and Bootstrap Capacitors
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Very-Small Form-Factor Application
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
      3. 9.2.3 Two-Output Sequenced-Startup Application
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
        3. 9.2.3.3 Application Curve
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Layout Considerations For Thermal Performance
    4. 10.4 Grounding and Powerpad Layout
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    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

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • PWP|20
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.1.2.2 Input Capacitors

The TPS54110 requires an input decoupling capacitor and, depending on the application, a bulk input capacitor. The minimum value for the decoupling capacitor, C9, is 10 uF. A high quality ceramic type X5R or X7R with a voltage rating greater than the maximum input voltage is recommended. A bulk input capacitor may be needed, especially if the TPS54110 circuit is not located within approximately 2 inches from the input voltage source. The capacitance value is not critical, but the voltage rating must be greater than the maximum input voltage including ripple voltage. The capacitor must filter the input ripple voltage to acceptable levels.

Input ripple voltage can be approximated by Equation 5:

Equation 5. TPS54110 equation2_lvs500.gif

where

  • IOUT(MAX) is the maximum load current
  • ƒSW is the switching frequency
  • CBULK is the bulk capacitor value
  • ESRMAX is the maximum series resistance of the bulk capacitor

Worst-case RMS ripple current is approximated by Equation 6:

Equation 6. TPS54110 equation3_lvs500.gif

In this case the input ripple voltage is 66 mV with a 10-µF bulk capacitor. Figure 14 shows the measured ripple waveform. The RMS ripple current is 0.75 A. The maximum voltage across the input capacitors is VINMAX + ΔVIN/2. The bypass capacitor and input bulk capacitor are each rated for 6.3 V and a ripple-current capacity of 1.5 A, providing some margin. It is very important that the maximum ratings for voltage and current are not exceeded under any circumstance.