SLVSB10F July   2012  – November 2020 TPS54020

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (Continued)
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings (1)
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  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  Input Voltage and Power Input Voltage Pins (VIN and PVIN)
      3. 8.3.3  Voltage Reference (VREF)
      4. 8.3.4  Adjusting the Output Voltage
      5. 8.3.5  Safe Start-up into Prebiased Outputs
      6. 8.3.6  Error Amplifier
      7. 8.3.7  Slope Compensation
      8. 8.3.8  Enable and Adjusting Undervoltage Lockout
      9. 8.3.9  Adjustable Switching Frequency and Synchronization (RT/CLK)
      10. 8.3.10 Soft-Start (SS) Sequence
      11. 8.3.11 Power Good (PWRGD)
      12. 8.3.12 Bootstrap Voltage (BOOT) and Low Dropout Operation
      13. 8.3.13 Sequencing (SS)
      14. 8.3.14 Output Overvoltage Protection (OVP)
      15. 8.3.15 Overcurrent Protection
        1. 8.3.15.1 High-side MOSFET Overcurrent Protection
        2. 8.3.15.2 Low-side MOSFET Overcurrent Protection
      16. 8.3.16 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Single-Supply Operation
      2. 8.4.2 Split Rail Operation
      3. 8.4.3 Continuous Current Mode Operation (CCM)
      4. 8.4.4 Eco-mode Light-Load Efficiency Operation
      5. 8.4.5 Adjustable Switching Frequency (RT Mode)
      6. 8.4.6 Synchronization (CLK Mode)
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Small Signal Model for Loop Response
      2. 9.1.2 Simple Small Signal Model for Peak Current Mode Control
      3. 9.1.3 Small Signal Model for Frequency Compensation
      4. 9.1.4 Designing the Device Loop Compensation
        1. 9.1.4.1 Step One: Determine the Crossover Frequency (fC)
        2. 9.1.4.2 Step Two: Determine a Value for R6
        3. 9.1.4.3 Step Three: Calculate the Compensation Zero.
        4. 9.1.4.4 Step Four: Calculate the Compensation Noise Pole.
        5. 9.1.4.5 Step Five: Calculate the Compensation Phase Boost Zero.
      5. 9.1.5 Fast Transient Considerations
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1  Custom Design With WEBENCH® Tools
        2. 9.2.2.2  Operating Frequency
        3. 9.2.2.3  Output Inductor Selection
        4. 9.2.2.4  Output Capacitor Selection
          1. 9.2.2.4.1 Response to a Load Transient
          2. 9.2.2.4.2 Output Voltage Ripple
          3. 9.2.2.4.3 Bus Capacitance
        5. 9.2.2.5  Input Capacitor Selection
        6. 9.2.2.6  Soft-Start Capacitor Selection
        7. 9.2.2.7  Bootstrap Capacitor Selection
        8. 9.2.2.8  Undervoltage Lockout Set Point
        9. 9.2.2.9  Output Voltage Feedback Resistor Selection
          1. 9.2.2.9.1 Minimum Output Voltage
        10. 9.2.2.10 Compensation Component Selection
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
        1. 12.1.1.1 Custom Design With WEBENCH® Tools
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Pin Configuration and Functions

GUID-771626D0-D1BA-4B83-9A41-3F2F666F889B-low.gif Figure 6-1 15-Pin VQFNRUW Package(Top View)
Table 6-1 Pin Functions
PIN I/O(1) DESCRIPTION
NAME NO.
BOOT 6 S A bootstrap capacitor is required between BOOT and PH. If the voltage on this capacitor is below the minimum required by the high-side MOSFET (BOOT UVLO), the PH node is forced low so that the capacitor is refreshed.
COMP 12 O Error amplifier current output, and input to the output switch current comparator. Connect frequency compensation to this pin.
EN 15 I A divider network must be used to implement an undervoltage lockout function. To disable switching and reduce quiescent current, this pin must be pulled to ground.
HICCUP 2 O Overcurrent protection scheme select pin
ILIM 3 O Current limit threshold select pin
PGND 9 G Power Ground. Return for the low-side MOSFET
PH 8 O Switch node
PVIN 7 I Power input. Supplies the power switches of the power converter
PWRGD 5 O Power-good fault pin. Asserts low if output voltage is out of regulation due to thermal shutdown, dropout, overvoltage, EN shutdown, or during soft start.
RT/CLK 10 I/O Automatically selects between RT mode and CLK mode. An external timing resistor adjusts the switching frequency of the device. In CLK mode, the device synchronizes to an external clock.
RTN 11 G Return for control circuitry
SS 14 I/O Soft-start pin. An external capacitor connected to this pin sets the internal voltage reference rise time. The voltage on this pin overrides the internal reference. It can be used for sequencing.
SYNC_OUT 4 O Synchronization output provides a clock signal 180° out-of-phase with the power switch.
VIN 1 I Supplies the control circuitry of the power converter
VSENSE 13 I Inverting node of the transconductance (gm) error amplifier
I = Input, O = Output, S = Supply, G = Ground Return