SLUUBL7A February   2017  – February 2022 TPS543C20

 

  1.   Trademarks
  2. 1 Introduction
    1. 1.1 Before You Begin
  3. 2 Description
    1. 2.1 Typical End-User Applications
    2. 2.2 EVM Features
  4. 3 EVM Electrical Performance Specifications
  5. 4 Schematic
  6. 5 Test Equipment
  7. 6 TPS543C20EVM-869
  8. 7 List of Test Points, Jumpers, and Switches
  9. 8 Test Procedure
    1. 8.1 Line and Load Regulation Measurement Procedure
    2. 8.2 Efficiency
    3. 8.3 Equipment Shutdown
  10. 9 Performance Data and Typical Characteristic Curves
    1. 9.1 Load Regulation
    2. 9.2 Efficiency
    3. 9.3 Power Loss
    4. 9.4 Transient Response
    5. 9.5 Output Ripple
    6. 9.6 Enable On
    7. 9.7 Control On and Off
    8. 9.8 Thermal Image
  11. 10EVM Assembly Drawing and PCB Layout
  12. 11List of Materials
  13. 12Revision History

8.2 Efficiency

To measure the efficiency of the power train on the EVM, it is important to measure the voltages at the correct location. This is necessary; otherwise, the measurements will include losses in efficiency that are not related to the power train itself. Losses incurred by the voltage drop in the copper traces and in the input and output connectors are not related to the efficiency of the power train, and they must not be included in efficiency measurements.

Table 8-2 List of Test Points for Efficiency Measurements
Test PointNode NameDescription
TP14VOUTSense VOUT+ locally across C9. Use for efficiency and ripple measurements.
TP3GNDSense VOUT– locally across C9. Use for efficiency and ripple measurements.
TP16 or TP18VINSense VIN + across C14 or C26
TP35 or TP33GNDSense VIN– across C14 or C26

Input current can be measured at any point in the input wires, and output current can be measured anywhere in the output wires of the output being measured. Using these measurement points result in efficiency measurements that do not include losses due to the connectors and PCB traces.