SLVSGW6 August   2024 TPS55287

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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 I2C Timing Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  VCC Power Supply
      2. 6.3.2  EXTVCC Power Supply
      3. 6.3.3  Operation Mode Setting
      4. 6.3.4  Input Undervoltage Lockout
      5. 6.3.5  Enable and Programmable UVLO
      6. 6.3.6  Soft Start
      7. 6.3.7  Shutdown and Load Discharge
      8. 6.3.8  Switching Frequency
      9. 6.3.9  Switching Frequency Dithering
      10. 6.3.10 Inductor Current Limit
      11. 6.3.11 Internal Charge Path
      12. 6.3.12 Output Voltage Setting
      13. 6.3.13 Output Current Monitoring and Cable Voltage Droop Compensation
      14. 6.3.14 Output Current Limit
      15. 6.3.15 Overvoltage Protection
      16. 6.3.16 Output Short Circuit Protection
      17. 6.3.17 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 PWM Mode
      2. 6.4.2 Power Save Mode
    5. 6.5 Programming
      1. 6.5.1 Data Validity
      2. 6.5.2 START and STOP Conditions
      3. 6.5.3 Byte Format
      4. 6.5.4 Acknowledge (ACK) and Not Acknowledge (NACK)
      5. 6.5.5 Target Address and Data Direction Bit
      6. 6.5.6 Single Read and Write
      7. 6.5.7 Multiread and Multiwrite
    6. 6.6 Register Maps
      1. 6.6.1 REF Register (Address = 0h, 1h)
      2. 6.6.2 IOUT_LIMIT Register (Address = 2h) [reset = 11100100h]
      3. 6.6.3 VOUT_SR Register (Address = 3h) [reset = 00000001h]
      4. 6.6.4 VOUT_FS Register (Address = 4h) [reset = 00000011h]
      5. 6.6.5 CDC Register (Address = 5h) [reset = 11100000h]
      6. 6.6.6 MODE Register (Address = 6h) [reset = 00100000h]
      7. 6.6.7 STATUS Register (Address = 7h) [reset = 00000011h]
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Switching Frequency
        2. 7.2.2.2 Output Voltage Setting
        3. 7.2.2.3 Inductor Selection
        4. 7.2.2.4 Input Capacitor
        5. 7.2.2.5 Output Capacitor
        6. 7.2.2.6 Output Current Limit
        7. 7.2.2.7 Loop Stability
      3. 7.2.3 Application Curves
  9. 8 Power Supply Recommendations
  10. 9 Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

6.3.7 Shutdown and Load Discharge

When the EN/UVLO pin voltage is pulled below 0.4 V, the TPS55287 is in shutdown mode, and all functions are disabled. All internal registers are reset to default values.

When the EN/UVLO pin is at a high logic level and the OE bit is cleared to 0, the TPS55287 turns off the switching operation but keeps the I2C interface active. Simultaneously, if the DISCHG bit in the register 06h is set to 1, the TPS55287 discharges the output voltage below 0.8 V by an internal constant current.

When the EN/UVLO pin is at high logic level, the TPS55287 output discharge current can also be enabled by setting the Force_DISCHG bit in the register 06h to 1. During output voltage transient from high voltage to low voltage, the output discharge current helps reduce the VOUT falling time in auto PFM mode or reduces the reverse current in FPWM mode. It's not recommended to enable the discharge FET longer than 10ms due to high power loss.