SLUSB56B November   2012  – April 2019 TPS53819A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Application
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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  Enable and Soft-Start
      2. 7.3.2  Adaptive On-Time Control
      3. 7.3.3  Zero Crossing Detection
      4. 7.3.4  Output Discharge Control
      5. 7.3.5  Low-Side Driver
      6. 7.3.6  High-Side Driver
      7. 7.3.7  Power Good
      8. 7.3.8  Current Sense and Overcurrent Protection
      9. 7.3.9  Overvoltage and Undervoltage Protection
      10. 7.3.10 Out-of-Bound Protection
      11. 7.3.11 UVLO Protection
      12. 7.3.12 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Light-Load Condition in Auto-Skip Operation (Eco-mode)
      2. 7.4.2 Forced Continuous Conduction Mode
      3. 7.4.3 D-CAP2™ Mode
    5. 7.5 Programming
      1. 7.5.1 PMBus General Descriptions
      2. 7.5.2 PMBus Slave Address Selection
      3. 7.5.3 PMBus Address Selection
      4. 7.5.4 Supported Formats
        1. 7.5.4.1 Direct Format: Write
        2. 7.5.4.2 Combined Format: Read
        3. 7.5.4.3 Stop-Separated Reads
      5. 7.5.5 Supported PMBus Commands
      6. 7.5.6 Unsupported PMBus Commands
    6. 7.6 Register Maps
      1. 7.6.1  OPERATION [01h] (R/W Byte)
      2. 7.6.2  ON_OFF_CONFIG [02h] (R/W Byte)
      3. 7.6.3  WRITE_PROTECT [10h] (R/W Byte)
      4. 7.6.4  CLEAR_FAULTS [03h] (Send Byte)
      5. 7.6.5  STORE_DEFAULT_ALL [11h] (Send Byte)
      6. 7.6.6  RESTORE_DEFAULT_ALL [12h] (Send Byte)
      7. 7.6.7  STATUS_WORD [79h] (Read Word)
      8. 7.6.8  CUSTOM_REG (MFR_SPECIFIC_00) [D0h] (R/W Byte)
      9. 7.6.9  DELAY_CONTROL (MFR_SPECIFIC_01) [D1h] (R/W Byte)
      10. 7.6.10 MODE_SOFT_START_CONFIG (MFR_SPECIFIC_02) [D2h] (R/W Byte)
      11. 7.6.11 FREQUENCY_CONFIG (MFR_SPECIFIC_03) [D3h] (R/W Byte)
      12. 7.6.12 VOUT_ADJUSTMENT (MFR_SPECIFIC_04) [D4h] (R/W Byte)
      13. 7.6.13 Output Voltage Fine Adjustment Soft Slew Rate
      14. 7.6.14 VOUT_MARGIN (MFR_SPECIFIC_05) [D5h] (R/W Byte)
      15. 7.6.15 Output Voltage Margin Adjustment Soft-Slew Rate
      16. 7.6.16 UVLO_THRESHOLD (MFR_SPECIFIC_06) [D6h]
  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  Switching Frequency
        3. 8.2.2.3  Inductor (L1)
        4. 8.2.2.4  Output Capacitors (C10, C11, C12, C13, C14)
        5. 8.2.2.5  Input Capacitors (C1, C2, C3, C4, C5)
        6. 8.2.2.6  MOSFET (Q1, Q2)
        7. 8.2.2.7  VREG Bypass Capacitor (C18)
        8. 8.2.2.8  VDD Bypass Capacitor (C19)
        9. 8.2.2.9  VBST Capacitor (C7)
        10. 8.2.2.10 Snubber (C8 and R9)
        11. 8.2.2.11 Feedback Resistance, RFBH and RFBL (R17 and R18)
        12. 8.2.2.12 Overcurrent Limit (OCL) Setting Resistance (R10)
        13. 8.2.2.13 PMBus Device Address (R3 and R4)
        14. 8.2.2.14 PGOOD Pullup Resistor (R2)
        15. 8.2.2.15 SCL and SDA Pulldown Resistors (R14 and R15)
        16. 8.2.2.16 PMBus Pullup Resistors
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 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

8.2.2.2 Switching Frequency

The switching frequency must first be decided on and is set using the PMBus. When deciding on a frequency a tradeoff between component size and efficiency must be made. A lower frequency reduces the switching losses in the MOSFETs improving efficiency but a larger inductance and/or output capacitance is required for low output voltage ripple. This example uses the TI default PMBus setting, 425 kHz.