SLVUC35A May   2021  – August 2021 TPS25946

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 EVM Features
    2. 1.2 EVM Applications
  3. 2Description
  4. 3Schematic
  5. 4General Configurations
    1. 4.1 Physical Access
    2. 4.2 Test Equipment and Set up
      1. 4.2.1 POWER SUPPLIES
      2. 4.2.2 METERS
      3. 4.2.3 OSCILLOSCOPE
      4. 4.2.4 LOADS
  6. 5Test Setup and Procedures
    1. 5.1 Hot Plug Test
    2. 5.2 Startup With a Combination of Capacitive and Resistive Loads
    3. 5.3 Power-Up into Short Test
    4. 5.4 Overvoltage Lockout Test
    5. 5.5 Transient Overload Performance
    6. 5.6 Overcurrent Test
    7. 5.7 Output Hot Short Test
    8. 5.8 USB On-The-Go (OTG) Performance
  7. 6EVAL Board Assembly Drawings and Layout Guidelines
    1. 6.1 PCB Drawings
  8. 7Bill Of Materials (BOM)
  9. 8Revision History

5.7 Output Hot Short Test

Use the following instructions to perform the output hot short test:

  1. Set the input supply voltage VIN to 12 V and current limit of 10 A. Turn ON the power supply.
  2. Short the output of the device for example, VOUT to PGND with a shorter cable.
  3. Observe the waveforms using an oscilloscope.

Figure 5-12 and Figure 5-13 show the test waveforms of output hot short on the TPS25946EVM eFuse Evaluation Board.

GUID-20210424-CA0I-ZTGV-HDSP-WGMHGSWRBDGG-low.gif Figure 5-12 Output Hot Short Response of TPS25946 Device (Vin = 12 V, Cout = 10 µF, ILIM = 549 Ω)
GUID-20210424-CA0I-0ZMN-V86D-HJHN5KTSW9PL-low.gif Figure 5-13 Output Hot Short Response (Zoomed) of TPS25946 Device (Vin = 12 V, Cout = 10 µF, ILIM = 549 Ω).
Note that it is very difficult to obtain repeatable and similar short-circuit testing results. The following contributes to the variation in results:
  • Source bypassing
  • Input leads
  • Board layout
  • Component selection
  • Output shorting method
  • Relative location of the short
  • Instrumentation
The actual short exhibits a certain degree of randomness because it microscopically bounces and arcs. Ensure that configuration and methods are used to obtain realistic results. Hence, do not expect to see waveforms exactly like the waveforms in this user's guide because every setup is different.