SLVSH35A October   2023  – February 2024 TPS274C65CP

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Switching Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Pin Diagrams
      2. 8.3.2 Programmable Current Limit
      3. 8.3.3 Protection Mechanisms
        1. 8.3.3.1 Over-current Protection
        2. 8.3.3.2 Short-Circuit Protection
          1. 8.3.3.2.1 VS During Short-to-Ground
        3. 8.3.3.3 Thermal Shutdown Behavior
        4. 8.3.3.4 Inductive-Load Switching-Off Clamp
        5. 8.3.3.5 Inductive Load Demagnetization
        6. 8.3.3.6 Thermal Shutdown
        7. 8.3.3.7 Undervoltage Protection on VS (UVP)
        8. 8.3.3.8 Undervoltage Lockout on Low Voltage Supply (VDD_UVLO)
        9. 8.3.3.9 Power-Up and Power-Down Behavior
      4. 8.3.4 Diagnostic Mechanisms
        1. 8.3.4.1 Fault Indication
        2. 8.3.4.2 Short-to-Battery and Open-Load Detection
    4. 8.4 Device Functional Modes
      1. 8.4.1 Off
      2. 8.4.2 Active
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 IEC 61000-4-5 Surge
        2. 9.2.2.2 Loss of GND
        3. 9.2.2.3 Paralleling Channels
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.3.2 Short-Circuit Protection

The TPS274C65CP provides output short-circuit protection to ensure that the device prevents current flow in the event of a low impedance path to GND, removing the risk of damage or significant supply droop. The TPS274C65CP is guaranteed to protect against short-circuit events regardless of the state of the ILIM pins.

Figure 8-5 shows the behavior of the TPS274C65CP when the device is enabled into a short circuit.

GUID-20240206-SS0I-VLDR-0T2B-1XCZHKPMZCVR-low.svg Figure 8-5 Enable into Short-Circuit Behavior

Due to the low impedance path, the output current rapidly increases until it hits the current limit threshold. Due to series inductance and deglitch, the measured maximum current can temporarily exceed the ICL value defined as ICL_ENPS, however, it settles to the current limit.

In this state, high power is dissipated in the FET, so eventually the internal thermal protection temperature for the FET is reached and the device safely shuts down. If the device is not configured in latch mode, the device waits tRETRY amount of time and turns the channel back on.

Figure 8-6 shows the behavior of the TPS274C65CP when a short-circuit occurs when the device is in the on-state and already outputting current. When the internal pass FET is fully enabled, the current clamping settling time is slower so to ensure overshoot is limit, the device implements a fast trip level at a level IOVCR. When this fast trip threshold is hit, the device immediately shuts off for a short period of time before quickly re-enabling and clamping the current to ICL_Reg level after a brief transient overshoot to the ICL_ENPS level. The device then keeps the current clamped at the regulation current limit until the thermal shutdown temperature is hit and the device safely shuts off.

GUID-20240206-SS0I-TBHJ-DSD7-VWCQJTMGKDTT-low.svg Figure 8-6 On-State Short-Circuit Behavior

Soft Short- Circuit Behavior shows the behavior of the TPS274C65CP when there is a small change in impedance that sends the load current above the ICL threshold. The current rises to ICL_LINPK since the FET is still in the linear mode. Then the current limit kicks in and the current drops to the ICL value.

GUID-20240206-SS0I-2KWD-48JK-G7RVKKWH7HSZ-low.svg Figure 8-7 Soft Short-Circuit Behavior

In all of these cases, the internal thermal shutdown is safe to hit repetitively. There is no device risk or lifetime reliability concerns from repeatedly hitting this thermal shutdown level.