SLVU381A August   2010  – September 2021 TPS54426

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Background
    2. 1.2 Performance Specification Summary
    3. 1.3 Modifications
      1. 1.3.1 Output Voltage Set Point
  3. 2Test Setup and Results
    1. 2.1  Input / Output Connections
    2. 2.2  Start-Up Procedure
    3. 2.3  Efficiency
    4. 2.4  Light Load Efficiency
    5. 2.5  Load Regulation
    6. 2.6  Line Regulation
    7. 2.7  Load Transient Response
    8. 2.8  Output Voltage Ripple
    9. 2.9  Input Voltage Ripple
    10. 2.10 Start=Up
  4. 3Board Layout
    1. 3.1 Layout
  5. 4Schematic, Bill of Materials and Reference
    1. 4.1 Schematic
    2. 4.2 Bill of Materials
    3. 4.3 Reference
  6. 5Revision History

Output Voltage Set Point

To change the output voltage of the EVMs, it is necessary to change the value of resistor R1. Changing the value of R1 can change the output voltage above 0.765 V. The value of R1 for a specific output voltage can be calculated using Equation 1 and Equation 2.

For output voltage from 0.76 V to 2.5 V:

Equation 1. GUID-E0D28873-3FBF-4A73-9E68-8B44EDAB13A4-low.gif

For output voltage over 2.5 V:

Equation 2. GUID-59708290-A81F-4EBA-AE2D-7D8484C6601C-low.gif

Table 1-3 lists the R1 value for some common output voltages. For higher output voltages of 1.8 V or above, a feedforward capacitor (C2) can be required to improve phase margin, and is recommended for auto skip Eco-mode stability. Pads for this component (C2) are provided on the printed circuit board. Note that the values given in Table 1-3 are standard values, and not the exact value calculated using Table 1-3.

Table 1-3 Output Voltages
OUTPUT VOLTAGE
(V)
R1
(kΩ)
R2
(kΩ)
C2
(pF)
L1
(µH)
1.06.8122.11.5
1.058.2522.11.5
1.212.722.11.5
1.830.122.110 - 222.2
2.549.922.110 - 222.2
3.373.222.110 - 222.2
5.012122.110 - 223.3