SLVU793A October   2012  – June 2021 TPS56921

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Background
    2. 1.2 Performance Specification Summary
    3. 1.3 Modifications
      1. 1.3.1 Output Voltage Setpoint
      2. 1.3.2 Slow-Start Time
      3. 1.3.3 Adjustable UVLO
      4. 1.3.4 Input Voltage Rails
  3. 2Test Setup and Results
    1. 2.1 Input/Output Connections
    2. 2.2 Efficiency
    3. 2.3 Output Voltage Load Regulation
    4. 2.4 Output Voltage Line Regulation
    5. 2.5 Load Transients
    6. 2.6 Loop Characteristics
    7. 2.7 Output Voltage Ripple
    8. 2.8 Input Voltage Ripple
    9. 2.9 Powering Up
  4. 3Board Layout
    1. 3.1 Layout
  5. 4Schematic and Bill of Materials
    1. 4.1 Schematic
    2. 4.2 Bill of Materials
  6. 5Revision History

1.3.3 Adjustable UVLO

The undervoltage lockout (UVLO) can be adjusted externally using R1 and R2. The EVM is set to use the internal UVLO and R1 and R2 are not populated. Use Equation 3 and Equation 4 to calculate required resistor values for different start and stop voltages.

Equation 3. GUID-B58CADDC-AF00-4451-800A-0F5EF56CC9CA-low.gif
Equation 4. GUID-0BA1DABC-D259-46AA-B44F-119AD374C4FC-low.gif