SLUSEY7B December   2022  – December 2024 TPSM82816

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  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 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 Precise Enable (EN)
      2. 7.3.2 Output Discharge
      3. 7.3.3 COMP/FSET
      4. 7.3.4 MODE/SYNC
      5. 7.3.5 Spread Spectrum Clocking (SSC)
      6. 7.3.6 Undervoltage Lockout (UVLO)
      7. 7.3.7 Power-Good Output (PG)
      8. 7.3.8 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Pulse Width Modulation (PWM) Operation
      2. 7.4.2 Power Save Mode Operation (PSM)
      3. 7.4.3 100% Duty-Cycle Operation
      4. 7.4.4 Current Limit and Short-Circuit Protection
      5. 7.4.5 Soft Start / Tracking (SS/TR)
  9. 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 Setting the Output Voltage
        2. 8.2.2.2 Feedforward Capacitor
        3. 8.2.2.3 Input Capacitor
        4. 8.2.2.4 Output Capacitor
      3. 8.2.3 Application Curves
    3. 8.3 System Examples
      1. 8.3.1 Voltage Tracking
      2. 8.3.2 Synchronizing to an External Clock
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
        1. 8.5.2.1 Thermal Consideration
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
    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

8.2.2.1 Setting the Output Voltage

The output voltage of the TPSM8281x is adjustable. Choose resistors R1 and R2 to set the output voltage within a range of 0.6 V to 5.5 V according to Equation 9. To keep the feedback (FB) net robust from noise, set R2 equal to or lower than 100 kΩ to have at least 6 µA of current in the voltage divider. Lower values of FB resistors achieve better noise immunity, and lower light load efficiency, as explained in the Design Considerations for a Resistive Feedback Divider in a DC/DC Converter analog design journal.

Equation 9. R1=R2× VOUTVFB -1=R2× VOUT0.6 V -1
Table 8-2 Examples for setting the Output Voltage
NOMINAL OUTPUT VOLTAGE VOUTR1R2Max CFF

at min Cout

OUTPUT VOLTAGE
0.8 V16.9 kΩ51 kΩ15 pF0.7988 V
1.0 V20 kΩ30 kΩ13 pF1.0 V
1.1 V39.2 kΩ47 kΩ6.8 pF1.101 V
1.2 V68 kΩ68 kΩ

3.9 pF

1.2 V
1.5 V76.8 kΩ51 kΩ

3.3 pF

1.5 V

1.8 V80.6 kΩ40.2 kΩ3.3 pF1.803 V
2.5 V47.5 kΩ15 kΩ5.6 pF2.5 V
3.3 V88.7 kΩ19.6 kΩ3 pF3.315 V