SLUU231A June   2006  – January 2022 TPS40074

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Description
    2. 1.2 Applications
    3. 1.3 Features
  3. 2TPS40074EVM-001 Electrical Performance Specifications
  4. 3Schematic
    1. 3.1 Adjusting Output Voltage (R5 and R6)
    2. 3.2 Using Remote Sense (J3)
    3. 3.3 5V Input Operation (R10 and R15)
  5. 4Test Setup
    1. 4.1 Equipment
      1. 4.1.1 Voltage Source
      2. 4.1.2 Meters
      3. 4.1.3 Loads
      4. 4.1.4 Recommended Wire Gauge
      5. 4.1.5 Other
    2. 4.2 Equipment Setup
      1. 4.2.1 Procedure
      2. 4.2.2 Diagram
    3. 4.3 Start-Up/Shutdown Procedure
    4. 4.4 Equipment Shutdown
  6. 5TPS40074EVM Typical Performance Data and Characteristic Curves
    1. 5.1 Efficiency
    2. 5.2 Line and Load Regulation
  7. 6EVM Assembly Drawings and Layout
  8. 7List of Materials
  9. 8Revision History

4.1.5 Other

FAN

This evaluation module includes components that can get hot to the touch, because this EVM is not enclosed to allow probing of circuit nodes, a small fan capable of 200–400 lfm is required to reduce component surface temperatures to prevent user injury. The EVM should not be left unattended while powered or probed while the fan is not running.

OSCILLOSCOPE

A 60-MHz or faster oscilloscope can be used to determine the ripple voltage on 1V5_OUT. The oscilloscope should be set for the following to take output ripple measurements:

  • 1-MΩ impedance
  • AC coupling
  • 1-μs/division horizontal resolution
  • 20-mV/division vertical resolution

TP15 and TP16 can be used to measure the output ripple voltage by placing the oscilloscope probe tip through TP15 and holding the ground barrel to TP16 as shown in Figure 4-2. For a hands-free approach, the loop in TP16 can be cut and opened to cradle the probe barrel. Using a leaded ground connection can induce additional noise due to the large ground loop area.