SLUU286A March   2008  – October 2021 TPS54286 , TPS54386

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Description
    2. 1.2 Applications
    3. 1.3 Features
  3. 2TPS54386EVM Electrical Performance Specifications
  4. 3Schematic
    1. 3.1 Sequencing Jump (JP3)
    2. 3.2 Enable Jumpers (JP1 and JP2)
    3. 3.3 Test Point Descriptions
      1. 3.3.1 Input Voltage Monitoring (TP1 and TP2)
      2. 3.3.2 Channel 1 Output Voltage Monitoring (TP3 and TP4)
      3. 3.3.3 Channel 1 Loop Analysis (TP5, TP6, TP7 and TP8)
      4. 3.3.4 Channel 1 Switching Waveforms (TP9 and TP10)
      5. 3.3.5 TPS54386 Device Ground (TP11)
      6. 3.3.6 Channel 2 Switching Waveforms (TP12 and TP13)
      7. 3.3.7 Channel 2 Loop Analysis (TP14, TP15, TP16 and TP17)
      8. 3.3.8 Output Voltage Monitoring (TP18 and TP19)
  5. 44 Test Set Up
    1. 4.1 Equipment
      1. 4.1.1 Voltage Source
      2. 4.1.2 Meters
      3. 4.1.3 Loads
      4. 4.1.4 Oscilloscope
      5. 4.1.5 Recommended Wire Gauge
      6. 4.1.6 Other
    2. 4.2 Equipment Setup
      1. 4.2.1 Procedure
      2. 4.2.2 Diagram
    3. 4.3 Start Up / Shut Down Procedure
    4. 4.4 Output Ripple Voltage Measurement Procedure
    5. 4.5 Control Loop Gain and Phase Measurement Procedure
    6. 4.6 Equipment Shutdown
  6. 5TPS54386EVM Typical Performance Data and Characteristic Curves
    1. 5.1 Efficiency
    2. 5.2 Line and Load Regulation
    3. 5.3 Output Voltage Ripple
    4. 5.4 Switch Node
    5. 5.5 Control Loop Bode Plot (low line, VIN = 8 V)
  7. 6EVM Assembly Drawings and Layout
  8. 7List of Materials
  9. 8Revision History

4.5 Control Loop Gain and Phase Measurement Procedure

  1. Connect 1 kHz to 1 MHz isolation transformer to TP6 and TP8 as show in Figure 4-3.
  2. Connect input signal amplitude measurement probe (Channel A) to TP8 as shown in Figure 4-3.
  3. Connect output signal amplitude measurement probe (Channel B) to TP6 as shown in Figure 4-3.
  4. Connect ground lead of Channel A and Channel B to TP5 & TP7 as shown in Figure 4-3.
  5. Inject 30 mV or less signal across R1 through isolation transformer.
  6. Sweep frequency from 1 kHz to 1 MHz with 10 Hz or lower post filter.
  7. Control loop gain can be measured by:GUID-AFD9308D-2065-440D-BDFC-30F079BAABFA-low.gif
  8. Control loop phase is measured by the phase difference between Channel A and Channel B.
  9. Control loop for Channel 2 can be measured by making the following substitutions.
    1. Change TP6 to TP16
    2. Change TP8 to TP14
    3. Change TP5 to TP17
    4. Change TP7 to TP15
  10. Disconnect isolation transformer before making any other measurements (signal injection into feedback may interfere with accuracy of other measurements).