SBAU227A March   2014  – June 2021 TPS56520 , TPS56720 , TPS56920 , TPS56C20

 

  1.   Trademarks
  2. 1Introduction
  3. 2Performance Specification Summary
  4. 3Modifications
    1. 3.1 Output Voltage Set Point
    2. 3.2 Output Voltage Set Point Using I2C Interface
      1. 3.2.1 PC Preparation
      2. 3.2.2 Connect the PC
      3. 3.2.3 Voltage Scaling Procedure
    3. 3.3 Output Filter and Closed Loop Response
  5. 4Test Setup and Results
    1. 4.1 Input/Output Connections
    2. 4.2 Start Up Procedure
    3. 4.3 Efficiency
    4. 4.4 Load Regulation
    5. 4.5 Line Regulation
    6. 4.6 Load Transient Response
    7. 4.7 Output Voltage Ripple
    8. 4.8 Start Up
    9. 4.9 Shut Down
  6. 5Board Layout
    1. 5.1 Board Layout
  7. 6Schematic, Bill of Materials and Reference
    1. 6.1 Schematic
    2. 6.2 Bill of Materials
    3. 6.3 Reference
  8. 7Revision History

3.1 Output Voltage Set Point

To change the output voltage of the TPS56C20EVM-614, change the value of resistor R7. Calculate the value of R7 for a specific output voltage between 0.6 V to 1.87 V using Equation 1.

Equation 1. VOUT = 0.6 × (1 + R7 / R8)

Table 3-1 lists the R7 values for common output voltages. For higher output voltages, a feed forward capacitor (C12) may be required to improve phase margin. The evaluation module provides pads to include the component (C12). NOTE: the values given in Table 3-1 are standard values and not the exact value.

Table 3-1 Output Voltages
Output Voltage (V)R7 (kΩ)R8 (kΩ)C12 (pF)L1 (µH)C6 + C7 (µF)
MINTYPMAX
0.87.3322
114.7221.01.52.244 – 100
1.118.2221.01.52.244 – 100
1.222221.01.52.244 – 100
1.533221.01.52.244 – 100
1.844.222Optional1.01.52.244 – 100