SLVUB77A July   2017  – October 2021 TPS54336A

 

  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
      2. 1.3.2 Adjustable UVLO
      3. 1.3.3 Adjustable Slow Start
  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 Powering Down
  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

1.3.1 Output Voltage Set Point

The voltage divider, R7 and R8, is used to set the output voltage. To change the output voltage of the EVM, it is necessary to change the value of resistor R8. Changing the value of R8 can change the output voltage above 0.8 V. The value of R8 for a specific output voltage can be calculated using Equation 1. Use 100 kΩ for R7.

Equation 1. GUID-0E09D01B-7C8F-4E3E-B8D5-E6CF77735314-low.gif

Table 1-3 lists the R9 and R10 values for some common output voltages. Note that VIN must be in a range so that the minimum on-time is greater than 145 ns, and the maximum duty cycle is less than 100%. The values given in Table 1-3 are standard values, not the exact value calculated using Equation 1.

Table 1-3 Output Voltages Available
OUTPUT VOLTAGE (V)R7 VALUE (kΩ)R8 VALUE (kΩ)
1.2100200
1.810080.6
2.510047.5
3.310032.4
5.010019.1