SLVUCB8A May   2022  – September 2022 TPS25985

 

  1.   TPS25985 evaluation module for eFuse User's Guide
  2.   Trademarks
  3. 1Introduction
    1. 1.1 EVM Features
    2. 1.2 EVM Applications
  4. 2Description
  5. 3Schematic
  6. 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 Loads
  7. 5Test Setup and Procedures
    1. 5.1  Hot Plug
    2. 5.2  Start-up with Enable
    3. 5.3  Difference Between Current Limit and DVDT Based Start-up Mechanisms
    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 PROCHOT# Implementation Using General-Purpose Comparator
    11. 5.11 Quick Output Discharge (QOD)
    12. 5.12 Thermal Performance of TPS25985EVM
  8. 6EVAL Board Assembly Drawings and Layout Guidelines
    1. 6.1 PCB Drawings
  9. 7Bill Of Materials (BOM)
  10. 8Revision History

5.4 Power-up into Short

Use the following instructions to perform the power-up into short test:

  1. Set the input supply voltage VIN to 12 V and current limit to 100 A. Connect the supply between VIN (Connector T1) and PGND (Connector T3) and keep the power supply OFF.

  2. Short the output of the EVM. For example, VOUT (Connector T2) to PGND (Connector T3) through a short and thick cable to make sure the short-circuited path impedance is minimum as possible.

  3. Configure the Jumper J6 position to desired reference voltage for overcurrent protection and active current sharing as mentioned in Table 4-3.

  4. Configure the jumpers J5 and J7 positions to the desired current limits during start-up as mentioned in Table 4-3.

  5. Keep the TPS25985 eFuses disabled by pushing the switch SW1.
  6. Turn ON the power supply.
  7. Enable the TPS25985 eFuse by releasing the switch SW1.

Figure 5-7 and Figure 5-8 show the test waveforms of power up into output short on the TPS25985EVM eFuse Evaluation Board with two (2) devices in parallel.

Note:

During powerup into short, a thermal foldback will result in the current flowing through the device being less than the calculated value of the current limit during start-up.

Figure 5-7 Power-up into Output Short Response of TPS25985 eFuse (VIN = 12 V, EN Stepped Up from 0 V to 3 V, RILIM = 402 Ω, RILIM2 = 402 Ω, RIREF = 40.2 kΩ, CITIMER = 22 nF, and OUT Shorted to PGND)
Figure 5-8 Power-up into Output Short Response of TPS25985 eFuse (VIN = 12 V, EN Stepped Up from 0 V to 3 V, RILIM = 402 Ω, RILIM2 = 402 Ω, RIREF = 40.2 kΩ, CITIMER = 22 nF, and OUT Shorted to PGND)