SLVU192B February   2007  – January 2022 TPS40077

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Description
    2. 1.2 Applications
    3. 1.3 Features
  3. 2TPS40077EVM-001 Electrical Performance Specifications
  4. 3Schematic
    1. 3.1 Adjusting Output Voltage (R3 and R13)
    2. 3.2 Disable (J3)
    3. 3.3 Test Set Up
      1. 3.3.1 Equipment
        1. 3.3.1.1 Voltage Source
        2. 3.3.1.2 Meters
        3. 3.3.1.3 Loads
        4. 3.3.1.4 Oscilloscope
        5. 3.3.1.5 Recommended Wire Gauge
    4. 3.4 Equipment Setup
      1. 3.4.1 Procedure
      2. 3.4.2 Diagram
    5. 3.5 Start-Up/Shut Down Procedure
    6. 3.6 Control Loop Gain and Phase Measurement Procedure
    7. 3.7 Equipment Shutdown
  5. 4TPS40077EVM Typical Performance Data and Characteristic Curves
    1. 4.1 Efficiency
    2. 4.2 Line and Load Regulation
    3. 4.3 Output Ripple
    4. 4.4 Transient Response
    5. 4.5 Bode Plot
  6. 5EVM Assembly Drawings and Layout
  7. 6List of Materials
  8. 7Revision History

3.1 Adjusting Output Voltage (R3 and R13)

The regulated output voltage can be adjusted within a limited range by changing the ground resistors in the feedback resistor-divider (R3, R13).

Table 3-1 contains common values for R3 and R13 to generate popular output voltages. The TPS40077EVM-001 is stable through these output voltages but the efficiency can suffer as the power stage is optimized for the 1.8-V output.

Table 3-1 Adjusting VOUT With R3
VOUT R3 R13
1.2 V 9.53 kΩ 62.0 kΩ
1.5 V 5.36 kΩ 140 kΩ
1.8 V 4.42 kΩ 24.9 kΩ
2.5 V 2.37 kΩ 71.5 kΩ
3.3 V 1.60 kΩ 220 kΩ