SLUUCY0A September   2023  – February 2024 TPSM861252 , TPSM861253 , TPSM861257

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5.   5
  6. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  7. 2Hardware
    1. 2.1 Input and Output Connections
    2. 2.2 Output Voltage Setpoint
    3. 2.3 Start-Up Procedure
  8. 3Implementation Results
    1. 3.1 Test Setup and Results
      1. 3.1.1 Efficiency
      2. 3.1.2 Load Regulation
      3. 3.1.3 Line Regulation
      4. 3.1.4 Load Transient Response
      5. 3.1.5 Start-Up
      6. 3.1.6 Shutdown
      7. 3.1.7 Output Voltage Ripple
  9. 4Hardware Design Files
    1. 4.1 Schematic
    2. 4.2 PCB Layout
    3. 4.3 Bill of Materials
  10. 5Additional Information
    1.     Trademarks
  11. 6Related Documentation
  12. 7Revision History

2.2 Output Voltage Setpoint

The output voltage of the TPSM861252/7EVM can be selected by changing the value of resistor R5 (RFBT) and R6 (RFBB). TI recommends using 1% tolerance or better divider resistors. Start with a 10kΩ or 30kΩ for R6 (RFBB) and use Equation 1 to calculate R5 (RFBT). To improve efficiency at light loads, consider using larger value resistors. If the values are too high, the regulator is more susceptible to noise and voltage errors from the FB input current are noticeable. The TPSM861253EVM is a fixed 3.3V output and does not need to select the divider resistors.

Equation 1. R 5 = R 6   × ( V o u t - 0.6 V ) 0.6 V