SNVSAU8A June   2017  – February 2024 TPS549B22

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 25-A FET
      2. 6.3.2 On-Resistance
      3. 6.3.3 Package Size, Efficiency and Thermal Performance
      4. 6.3.4 Soft-Start Operation
      5. 6.3.5 VDD Supply Undervoltage Lockout (UVLO) Protection
      6. 6.3.6 EN_UVLO Pin Functionality
      7. 6.3.7 Fault Protections
        1. 6.3.7.1 Current Limit (ILIM) Functionality
        2. 6.3.7.2 VDD Undervoltage Lockout (UVLO)
        3. 6.3.7.3 Overvoltage Protection (OVP) and Undervoltage Protection (UVP)
        4. 6.3.7.4 Out-of-Bounds Operation
        5. 6.3.7.5 Overtemperature Protection
    4. 6.4 Device Functional Modes
      1. 6.4.1 D-CAP3™ Control Mode Topology
      2. 6.4.2 DCAP Control Topology
    5. 6.5 Programming
      1. 6.5.1 Programmable Pin-Strap Settings
        1. 6.5.1.1 Address Selection (ADDR) Pin
        2. 6.5.1.2 VSEL Pin
        3. 6.5.1.3 D-CAP3™ Control Mode Selection
        4. 6.5.1.4 Application Workaround to Support 4-ms and 8-ms SS Settings
      2. 6.5.2 Programmable Analog Configurations
        1. 6.5.2.1 RSP/RSN Remote Sensing Functionality
          1. 6.5.2.1.1 Output Differential Remote Sensing Amplifier
        2. 6.5.2.2 Power Good (PGOOD Pin) Functionality
      3. 6.5.3 PMBus Programming
        1. 6.5.3.1 TPS549B22 Limitations to the PMBUS Specifications
        2. 6.5.3.2 Target Address Assignment
        3. 6.5.3.3 PMBUS Address Selection
        4. 6.5.3.4 Supported Formats
          1. 6.5.3.4.1 Direct Format — Write
          2. 6.5.3.4.2 Combined Format — Read
        5. 6.5.3.5 Stop Separated Reads
        6. 6.5.3.6 Supported PMBUS Commands and Registers
  8. Register Maps
    1. 7.1  OPERATION Register (address = 1h)
    2. 7.2  ON_OFF_CONFIG Register (address = 2h)
    3. 7.3  CLEAR FAULTS (address = 3h)
    4. 7.4  WRITE PROTECT (address = 10h)
    5. 7.5  STORE_DEFAULT_ALL (address = 11h)
    6. 7.6  RESTORE_DEFAULT_ALL (address = 12h)
    7. 7.7  CAPABILITY (address = 19h)
    8. 7.8  VOUT_MODE (address = 20h)
    9. 7.9  VOUT_COMMAND (address = 21h)
    10. 7.10 VOUT_MARGIN_HIGH (address = 25h) ®
    11. 7.11 VOUT_MARGIN_LOW (address = 26h)
    12. 7.12 STATUS_BYTE (address = 78h)
    13. 7.13 STATUS_WORD (High Byte) (address = 79h)
    14. 7.14 STATUS_VOUT (address = 7Ah)
    15. 7.15 STATUS_IOUT (address = 7Bh)
    16. 7.16 STATUS_CML (address = 7Eh)
    17. 7.17 MFR_SPECIFIC_00 (address = D0h)
    18. 7.18 MFR_SPECIFIC_01 (address = D1h)
    19. 7.19 MFR_SPECIFIC_02 (address = D2h)
    20. 7.20 MFR_SPECIFIC_03 (address = D3h)
    21. 7.21 MFR_SPECIFIC_04 (address = D4h)
    22. 7.22 MFR_SPECIFIC_06 (address = D6h)
    23. 7.23 MFR_SPECIFIC_07 (address = D7h)
    24. 7.24 MFR_SPECIFIC_44 (address = FCh)
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 TPS549B22 1.5-V to 18-V Input, 1-V Output, 25-A Converter
      2. 8.2.2 Design Requirements
      3. 8.2.3 Detailed Design Procedure
        1. 8.2.3.1  Custom Design With WEBENCH® Tools
        2. 8.2.3.2  Switching Frequency Selection
        3. 8.2.3.3  Inductor Selection
        4. 8.2.3.4  Output Capacitor Selection
          1. 8.2.3.4.1 Minimum Output Capacitance to Make Sure of Stability
          2. 8.2.3.4.2 Response to a Load Transient
          3. 8.2.3.4.3 Output Voltage Ripple
        5. 8.2.3.5  Input Capacitor Selection
        6. 8.2.3.6  Bootstrap Capacitor Selection
        7. 8.2.3.7  BP Pin
        8. 8.2.3.8  R-C Snubber and VIN Pin High-Frequency Bypass
        9. 8.2.3.9  Optimize Reference Voltage (VSEL)
        10. 8.2.3.10 MODE Pin Selection
        11. 8.2.3.11 ADDR Pin Selection
        12. 8.2.3.12 Overcurrent Limit Design
      4. 8.2.4 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Examples
      3. 8.4.3 Mounting and Thermal Profile Recommendation
  10. Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RVF|40
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Current Limit (ILIM) Functionality

GUID-5C1E4864-2622-4B0E-A634-FD6B75E8B40E-low.gifFigure 6-4 Current Limit Resistance vs OCP Valley Overcurrent Limit

The ILIM pin sets the OCP level. Connect the ILIM pin to GND through the voltage setting resistor, RILIM. To provide both good accuracy and a cost-effective solution, the TPS549B22 device supports temperature compensated internal MOSFET RDS(on) sensing.

Also, the TPS549B22 device performs both positive and negative inductor current limiting with the same magnitudes. The positive current limit normally protects the inductor from saturation that causes damage to the high-side FET and low-side FET. The negative current limit protects the low-side FET during OVP discharge.

The voltage between GND pin and SW pin during the OFF time monitors the inductor current. The current limit has 1200 ppm/°C temperature slope to compensate the temperature dependency of the on-resistance (RDS(on)). The GND pin is used as the positive current sensing node.

The TPS549B22 device uses cycle-by-cycle over-current limiting control. The inductor current is monitored during the OFF-state and the controller maintains the OFF-state during the period that the inductor current is larger than the overcurrent ILIM level. VILIM sets the valley level of the inductor current.