SLVUCH7A september   2022  – june 2023 TPS25990

 

  1.   1
  2.   TPS25990EVM: Evaluation Module for TPS25990 eFuse
  3.   Trademarks
  4. 1Introduction
    1. 1.1 EVM Features
    2. 1.2 EVM Applications
  5. 2Description
  6. 3Schematic
  7. 4General Configurations
    1. 4.1 Physical Access
    2. 4.2 Test Equipment and Setup
      1. 4.2.1 Power supplies
      2. 4.2.2 Meters
      3. 4.2.3 Oscilloscope
      4. 4.2.4 USB-to-GPIO Interface Adapter
      5. 4.2.5 Loads
  8. 5Test Setup and Procedures
    1. 5.1  Hot Plug
    2. 5.2  Start-up with Enable
    3. 5.3  Current Limit Based Start-up Behavior
    4. 5.4  Power Up into Short
    5. 5.5  Overvoltage Lockout
    6. 5.6  Transient Overload Performance
    7. 5.7  Overcurrent Event
    8. 5.8  Provision to Apply Load Transient and Overcurrent Event Using an Onboard Switching Circuit
    9. 5.9  Output Hot Short
    10. 5.10 Quick Output Discharge (QOD)
    11. 5.11 Thermal Performance of TPS25990EVM
  9. 6Using the TPS25990EVM-GUI
    1. 6.1 Access the TPS25990EVM-GUI
    2. 6.2 Introduction to the TPS25990EVM-GUI
    3. 6.3 Establishing Communication Between the EVM and GUI
    4. 6.4 Quick Info
    5. 6.5 Configuration
    6. 6.6 Telemetry
    7. 6.7 Blackbox
    8. 6.8 Register Map Page
  10. 7EVAL Board Assembly Drawings and Layout Guidelines
    1. 7.1 PCB Drawings
  11. 8Bill Of Materials (BOM)
  12. 9Revision History

5.9 Output Hot Short

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

  1. Set the input supply voltage VIN to 12 V and connect the power supply between VIN (Connector T1) and PGND (Connector T3).
  2. Turn ON the power supply.
  3. Short the output of the device for example, VOUT (Connector T2) to PGND (Connector T3) through a shorter cable, which is just enough to insert a 150 A current probe.
  4. Observe the waveforms using an oscilloscope.

Figure 5-15 shows the test waveforms of output hot short on the TPS25990EVM with one (1) TPS25990 eFuse and one (1) TPS25985 eFuse in parallel.

GUID-59E737C6-67FF-4A98-A07D-502747E046AE-low.svg Figure 5-15 Output Hot Short Response in TPS25990EVM (VIN = 12 V, RIMON = 1.47 ∥ 1.1 kΩ, VIREF = 1 V, and COUT = 10 µF)
Tip: Make sure there is sufficient input capacitor to eliminate voltage dips at the input. A combination of electrolytic and ceramic capacitors are preferred. With these capacitors, a large current can be provided for a short period of time during short-circuit.

Note that to obtain repeatable and similar short-circuit testing results is difficult. 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 the actual short microscopically bounces and arcs. Verify 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.