SNVU651 January   2019

 

  1.   TPS65653-Q1 EVM user's guide
    1.     Trademarks
    2. 1 Related Documentation from Texas Instruments
    3. 2 FCC Warning
    4. 3 If You Need Assistance
  2.   Using the TPS65653-Q1 Evaluation Module
    1. 4 Introduction
    2. 5 Setup
      1. 5.1 Input/Output Connector Description
      2. 5.2 Software Installation
      3. 5.3 Power Supply Setup
      4. 5.4 Notes on Efficiency Measurement Procedure
    3. 6 GUI Overview
      1. 6.1 Main Tab
      2. 6.2 Other Tabs and Menus
      3. 6.3 Console
    4. 7 Board Layout
    5. 8 Evaluation Board Schematic
    6. 9 Bill of Materials
  3.   Revision History

5.4 Notes on Efficiency Measurement Procedure

Output Connections: An appropriate electronic load or high-power system source meter instrument, specified for operation down to 700 mV, is desirable for loading the EVM. The maximum load current is specified as 8 A. Be sure to choose the correct wire size when attaching the electronic load. A wire resistance that is too high causes a voltage drop in the power distribution path, which becomes significant compared to the absolute value of the output voltage. Connect an electric load to J14 or J16. It is advised that, prior to connecting the load, it be set to sink 0 A to avoid power surges or possible shocks.

Voltage drop across the PCB traces yield inaccurate efficiency measurements. For the most accurate voltage measurement at the EVM, use J6 to measure the input voltage and J7 to measure the output voltage.

To measure the current flowing to/from the UUT, use the current meter of the DC power supply/electric load as long as it is accurate. Some power source ammeters may show offset of several milliamps and thus yields inaccurate efficiency measurements. In order to perform very accurate IQ measurements on the EVM, disconnect input protective Zener diode D1 by removing the shunt J5 from the board. When connected, this diode will cause some leakage, especially at high VIN voltages.