JAJSN87A July   2022  – December 2022 TPS1HC30-Q1

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 推奨動作条件
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 SNS Timing Characteristics
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Accurate Current Sense
      2. 8.3.2 Programmable Current Limit
        1. 8.3.2.1 Capacitive Charging
      3. 8.3.3 Inductive-Load Switching-Off Clamp
      4. 8.3.4 Full Protections and Diagnostics
        1. 8.3.4.1  Short-Circuit and Overload Protection
        2. 8.3.4.2  Open-Load and Short-to-Battery Detection
        3. 8.3.4.3  Short-to-Battery Detection
        4. 8.3.4.4  Reverse-Polarity and Battery Protection
        5. 8.3.4.5  Latch-Off Mode
        6. 8.3.4.6  Thermal Protection Behavior
        7. 8.3.4.7  UVLO Protection
        8. 8.3.4.8  Loss of GND Protection
        9. 8.3.4.9  Loss of Power Supply Protection
        10. 8.3.4.10 Reverse Current Protection
        11. 8.3.4.11 Protection for MCU I/Os
      5. 8.3.5 Diagnostic Enable Function
    4. 8.4 Device Functional Modes
      1. 8.4.1 Working Mode
  9. 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 Dynamically Changing Current Limit
        2. 9.2.2.2 EMC Transient Disturbances Test
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
        1. 9.4.2.1 Without a GND Network
        2. 9.4.2.2 With a GND Network
      3. 9.4.3 Thermal Considerations
  10. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 ドキュメントの更新通知を受け取る方法
    3. 10.3 サポート・リソース
    4. 10.4 Trademarks
    5. 10.5 静電気放電に関する注意事項
    6. 10.6 用語集
  11. 11Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8.3.4.1 Short-Circuit and Overload Protection

TPS1HC30-Q1 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 device is assured to protect against short-circuit events regardless of the state of the ILIM pins and with up to 28-V supply at 125°C.

The following figure shows the behavior of the TPS1HC30-Q1 when the device is enabled into a short circuit.

Figure 8-12 Enable into Short-Circuit Behavior (LATCH=0)

Due to the low impedance path, the output current rapidly increases until it hits the current limit threshold. Due to the response time of the current limiting circuit, the measured maximum current can temporarily exceed the ICL value defined as ICL_ENPS, however, it settles to the current limit regulation value.

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. Then, if LATCH pin is low, the part waits tRETRY amount of time and turns back on.

#T5791258-3 shows the behavior of the TPS1HC30-Q1 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 limited 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 level after a brief transient overshoot to the higher peak current (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.

Figure 8-13 On-State Short-Circuit Behavior

Overload Behavior shows the behavior of the TPS1HC30-Q1 when there is a small change in impedance that sends the load current above the ICL threshold. The current rises to ICL_LINPK above the regulation level. Then the current limit regulation loop kicks in and the current drops to the ICL value.

Figure 8-14 Overload 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.