SLVU659C March   2012  – June 2021 TPS62125

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Background
    2. 1.2 Performance Specification
    3. 1.3 Modifications
      1. 1.3.1 Input and Output Capacitors
      2. 1.3.2 Feedforward Capacitor
      3. 1.3.3 Loop Response Measurement
  3. 2Setup
    1. 2.1 Input/Output Connector Descriptions
    2. 2.2 Setup
  4. 3TPS62125EVM-044 Test Results
  5. 4Board Layout
  6. 5TPS62125EVM-044 Photos
  7. 6Schematic and Bill of Materials
    1. 6.1 Schematic
    2. 6.2 Bill of Materials
  8. 7Revision A files
    1. 7.1 Board Layout
    2. 7.2 Schematic and Bill of Materials
      1. 7.2.1 Schematic
      2. 7.2.2 Bill of Materials
  9. 8Revision History

1.3.3 Loop Response Measurement

The loop response of the EVM can be measured with two simple changes to the circuitry. First, cut the trace between the VOS pin and the inductor on the top layer. This change is shown in Figure 1-1. Second, install a 10-Ω resistor across the resistor pads on the back of the PCB at R7. The pads are spaced to allow installation of an 0603-sized resistor. With these changes, an ac signal (10-mV, peak-to-peak amplitude recommended) can be injected into the control loop across the added resistor. Details of measuring the control loop of DCS-Control devices are found in How to Measure the Control Loop of DCS-Control™ Devices. Figure 3-1 shows the results of this test.

GUID-85E3E155-B2C3-420C-BA8C-2ED2910A9E14-low.gifFigure 1-1 Loop Response Measurement Modification