SLVU479A October   2011  – August 2021 TPS54821

 

  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 Track In
      4. 1.3.4 Adjustable UVLO
      5. 1.3.5 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
    10. 2.10 Pre-Bias Start-Up
    11. 2.11 Hiccup-Mode Current Limit
  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

Slow-Start Time

The slow-start time can be adjusted by changing the value of C8. Use Equation 2 to calculate the required value of C8 for a desired slow-start time.

Equation 2. GUID-FCE2EE08-F8AD-4B81-8EA3-CD7A7B8E1929-low.gif

The EVM is set for a slow-start time of 5.7 ms using C8 = 0.022 µF.