SNVU745A January   2021  – May 2021 TPS62901 , TPS62902 , TPS62903

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Performance Specification
    2. 1.2 Modifications
      1. 1.2.1 Input and Output Capacitors
      2. 1.2.2 Configurable Enable Threshold Voltage
      3. 1.2.3 SS/TR Capacitor
      4. 1.2.4 Feedforward Capacitor
      5. 1.2.5 MODE/S-CONF Resistor
      6. 1.2.6 Loop Response Measurement
  3. 2Setup
    1. 2.1 Input/Output Connector Descriptions
  4. 3Safety Instructions
  5. 4 Test Results
  6. 5 Board Layout
  7. 6Schematic and Bill of Materials
    1. 6.1 Schematic
    2. 6.2 Bill of Materials
  8. 7Revision History

1.2.6 Loop Response Measurement

The loop response can be measured with simple changes to the circuitry. First, install a 10-Ω resistor across R9's pads on the back of the PCB. The pads are spaced to allow installation of an 0603-sized resistor. Next, cut the short section of trace on the top layer between the via on pin 3 and C2. Figure 1-1 shows this change. With these changes, an AC signal (10-mV, peak-to-peak amplitude recommended) can be injected into the control loop across the added 10-Ω resistor. Figure 4-2 shows the results of this test.

GUID-20210106-CA0I-KVTL-KMJC-XZM03BFJCKDC-low.png Figure 1-1 Loop Response Measurement Modification (Top Layer)