SLVSHR7 August   2024 TPSM8287A12M , TPSM8287A15M

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options
  6. 5 Pin Configuration and Functions
  7. 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 I2C Interface Timing Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Fixed-Frequency DCS-Control Topology
      2. 7.3.2  Forced-PWM and Power Save Modes
      3. 7.3.3  Precise Enable
      4. 7.3.4  Start-Up
      5. 7.3.5  Switching Frequency Selection
      6. 7.3.6  Output Voltage Setting
        1. 7.3.6.1 Output Voltage Setpoint
        2. 7.3.6.2 Output Voltage Range
        3. 7.3.6.3 Non-Default Output Voltage Setpoint
        4. 7.3.6.4 Dynamic Voltage Scaling (DVS)
      7. 7.3.7  Compensation (COMP)
      8. 7.3.8  Mode Selection / Clock Synchronization (MODE/SYNC)
      9. 7.3.9  Spread Spectrum Clocking (SSC)
      10. 7.3.10 Output Discharge
      11. 7.3.11 Undervoltage Lockout (UVLO)
      12. 7.3.12 Overvoltage Lockout (OVLO)
      13. 7.3.13 Overcurrent Protection
        1. 7.3.13.1 Cycle-by-Cycle Current Limiting
        2. 7.3.13.2 Hiccup Mode
        3. 7.3.13.3 Current-Limit Mode
      14. 7.3.14 Power Good (PG)
        1. 7.3.14.1 Power-Good Standalone, Primary Device Behavior
        2. 7.3.14.2 Power-Good Secondary Device Behavior
      15. 7.3.15 Remote Sense
      16. 7.3.16 Thermal Warning and Shutdown
      17. 7.3.17 Stacked Operation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power-On Reset (POR)
      2. 7.4.2 Undervoltage Lockout
      3. 7.4.3 Standby
      4. 7.4.4 On
    5. 7.5 Programming
      1. 7.5.1 Serial Interface Description
      2. 7.5.2 Standard-, Fast-, Fast-Mode Plus Protocol
      3. 7.5.3 I2C Update Sequence
      4. 7.5.4 I2C Register Reset
  9. 8 Device Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Selecting the Input Capacitors
        2. 9.2.2.2 Selecting the Target Loop Bandwidth
        3. 9.2.2.3 Selecting the Compensation Resistor
        4. 9.2.2.4 Selecting the Output Capacitors
        5. 9.2.2.5 Selecting the Compensation Capacitor, CComp1
        6. 9.2.2.6 Selecting the Compensation Capacitor, CComp2
      3. 9.2.3 Application Curves
    3. 9.3 Typical Application Using Four TPSM8287A1xM in Parallel Operation
      1. 9.3.1 Design Requirements
      2. 9.3.2 Detailed Design Procedure
        1. 9.3.2.1 Selecting the Input Capacitors
        2. 9.3.2.2 Selecting the Target Loop Bandwidth
        3. 9.3.2.3 Selecting the Compensation Resistor
        4. 9.3.2.4 Selecting the Output Capacitors
        5. 9.3.2.5 Selecting the Compensation Capacitor, CComp1
        6. 9.3.2.6 Selecting the Compensation Capacitor, CComp2
      3. 9.3.3 Application Curves
    4. 9.4 Power Supply Recommendations
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information

Package Options

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

9.3.2.1 Selecting the Input Capacitors

The TPSM8287A1xM devices feature a butterfly or parallel layout with two pairs of VIN and GND pins on opposite sides of the package.

The duty cycle of the converter is given by:

Equation 40. D=VOUTη×VIN
Equation 41. D=0.600.78×2.7=0.284

The value of input capacitance needed to meet any system-level input voltage ripple requirement is given by Equation 42. For this example, the lowest input voltage and highest load current are used to generate a worst case input voltage ripple of 100mV.

Equation 42. CIN=D×(1-D)×IOUTVIN(PP)×fsw
Equation 43. C I N = 0.284 × 1 - 0.284 × 12.0 0.1 × 1.5 × 10 6 = 16.3 μ F

The value of CIN calculated with Equation 42 is the effective capacitance after all derating, tolerance, and aging effects have been considered. In this parallel configuration, make sure to distribute the calculated input capacitance equally across all phases.