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

5.3 Current Limit Based Start-up Behavior

Use the following instructions to perform the start-up with current limit test:
  1. Configure the jumper J3 position to the desired slew rate mentioned in Table 4-3.
  2. Configure the jumpers J4 and J5 positions to the desired current limits during start-up as mentioned in Table 4-3.
  3. The reference voltage for overcurrent protection and active current sharing is at 1 V by default. The reference voltage can also be programmed via PMBus using the VIREF (E0h) register if another reference voltage is needed in the range of 0.3 V to 1.2 V.
  4. Set the input supply voltage VIN to 12 V and current limit to 100 A.
  5. Connect a load of 0.45 Ω between VOUT (Connector T2) and PGND (Connector T3).
  6. Connect the input supply between VIN (Connector T1) and PGND (Connector T3).
  7. Turn on the power supply by keeping the device disabled using the switch SW1.
  8. Enable the eFuse by releasing the switch SW1.
  9. Observe the waveform at VOUT (TP4) and input current using an oscilloscope. The main intention of this test is to observe the output voltage and input current profiles and time required to complete the inrush with two different current limit set points during start-up having all other test conditions identical. The inrush current hits the current limit set point in one case, but does not in the next.

Figure 5-5 shows the current limit-based start-up behavior on the TPS25990EVM having one TPS25990 eFuse and one TPS25985 eFuse in parallel with RILIM(TPS25990) of 665 Ω and RLIM(TPS25985) of 499 Ω.

GUID-20220906-SS0I-5VFR-QQRW-DLDLBSNJCG79-low.svg Figure 5-5 Start-up with Current Limit Response in TPS25990EVM (VIN = 12 V, EN Stepped Up from 0 V to 3 V, RILIM(TPS25990) = 665 Ω, RLIMI(TPS25985) = 499 Ω, VIREF = 1 V, COUT = 18.47 mF, RLOAD = 0.45 Ω, and CDVDT = 33 nF)