SLVSI15B March   2025  – October 2026 TPSM8287B15 , TPSM8287B30

PRODMIX  

  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 Requirements
    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  Output Voltage Setting
        1. 7.3.5.1 Output Voltage Setpoint
        2. 7.3.5.2 Output Voltage Range
        3. 7.3.5.3 Non-Default Output Voltage Setpoint
        4. 7.3.5.4 Dynamic Voltage Scaling (DVS)
        5. 7.3.5.5 Droop Compensation
      6. 7.3.6  Compensation (COMP)
      7. 7.3.7  Mode Selection / Clock Synchronization (MODE/SYNC)
      8. 7.3.8  Spread Spectrum Clocking (SSC)
      9. 7.3.9  Output Discharge
      10. 7.3.10 Undervoltage Lockout (UVLO)
      11. 7.3.11 Overvoltage Lockout (OVLO)
      12. 7.3.12 Overcurrent Protection
        1. 7.3.12.1 Cycle-by-Cycle Current Limiting
        2. 7.3.12.2 Hiccup Mode
        3. 7.3.12.3 Current-Limit Mode
      13. 7.3.13 Power Good (PG)
        1. 7.3.13.1 Power-Good Standalone, Primary Device Behavior
        2. 7.3.13.2 Power-Good Secondary Device Behavior
      14. 7.3.14 Remote Sense
      15. 7.3.15 Thermal Warning and Shutdown
      16. 7.3.16 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 HS-Mode Protocol
      4. 7.5.4 I2C Update Sequence
      5. 7.5.5 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 Two TPSM8287B30x 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
        1. 9.5.2.1 Thermal Considerations
  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

Design Requirements

The following table lists the operating parameters for this application example with the TPSM8287B30LAPx device.

Table 9-2 Design Parameters
SYMBOLPARAMETERVALUE
VINInput voltage2.7V – 6.0V
VOUTOutput voltage0.60V
TOLVOUTOutput voltage tolerance allowed by the application±5.0%
TOLDCOutput voltage tolerance of the TPSM8287Bxx (DC accuracy)±0.8%
ΔIOUT(step)Output current load step±3.0A
ttLoad step transition time1μs
fSWSwitching frequency1.5MHz
LIntegrated inductor50nH
TOLINDIntegrated inductor tolerance±20%
gmError amplifier transconductance1.5mS
τEmulated current time constant12.5μs
BWτTarget loop bandwidth200kHz
NΦNumber of paralleled devices (phases)1

Preliminary Calculations

The maximum allowable deviation of the power supply is ±5.0%. The DC accuracy of the TPSM8287Bxx is specified as ±0.8%, and therefore the maximum output voltage variation during a transient is given by:

Equation 5. ∆VOUT=±VOUT×(TOLVOUT–TOLDC)
Equation 6. ∆VOUT=±0.6 × (5.0% – 0.8%)=±25.2mV

Equation 32 calculates the peak-to-peak inductor current ripple, which is the greatest at the maximum input voltage:

Equation 7. IL(PP)=VOUTVIN(max)VIN(max) – VOUTL×fsw×NΦ
Equation 8. IL(PP)=0.66.06.0 – 0.650×10–9×1.5×106×1=7.2A

The maximum load step occurs when the load step from the application occurs at exactly the same time as the peak (or trough) of the inductor ripple current, and is given by:

Equation 9. ∆IOUT(max)=∆IOUT(step)+∆IL(PP)2
Equation 10. ∆IOUT(max)=3.0+7.22=6.6A