JAJSNC4A november   2021  – may 2023 TPS62441 , TPS62442

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  9. 8 Parameter Measurement Information
    1. 8.1 Schematic
  10. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Precise Enable (EN)
      2. 9.3.2 COMP/FSET
      3. 9.3.3 MODE/SYNC
      4. 9.3.4 Undervoltage Lockout (UVLO)
      5. 9.3.5 Power-Good Output (PG)
      6. 9.3.6 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Pulse Width Modulation (PWM) Operation
      2. 9.4.2 Power Save Mode Operation (PWM/PFM)
      3. 9.4.3 100% Duty-Cycle Operation
      4. 9.4.4 Current Limit and Short-Circuit Protection
      5. 9.4.5 Output Discharge
      6. 9.4.6 Soft Start
  11. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Programming the Output Voltage
      2. 10.1.2 External Component Selection
        1. 10.1.2.1 Inductor Selection
        2. 10.1.2.2 Capacitor Selection
          1. 10.1.2.2.1 Input Capacitor
          2. 10.1.2.2.2 Output Capacitor
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
    3. 10.3 Power Supply Recommendations
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 サード・パーティ製品に関する免責事項
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 ドキュメントの更新通知を受け取る方法
    4. 11.4 サポート・リソース
    5. 11.5 Trademarks
    6. 11.6 静電気放電に関する注意事項
    7. 11.7 用語集
  13. 12Mechanical, 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

9.4.4 Current Limit and Short-Circuit Protection

The TPS6244x is protected against overload and short circuit events. The converter is not switching with the fixed frequency when in current limit. The converter resumes the fixed frequency operation when the converter leaves current limit condition. If the inductor current exceeds the current limit, ILIMH, the high-side switch is turned off and the low-side switch is turned on to ramp down the inductor current. The high-side switch turns on again only if the current in the low-side switch has decreased below the low-side current limit. This can cause bursts or single pulses between the high-side and low-side current limit. Due to internal propagation delay, the actual current can exceed the static current limit. The dynamic current limit is given as:

Equation 4. I p e a k t y p = I L I M H + V L L × t P D

where

  • ILIMH is the static current limit as specified in the electrical characteristics.
  • L is the effective inductance at the peak current.
  • VL is the voltage across the inductor (VIN – VOUT).
  • tPD is the internal propagation delay of typically 50 ns.

The current limit can exceed static values, especially if the input voltage is high and very small inductances are used. The dynamic high-side switch peak current can be calculated as follows:

Equation 5. I p e a k t y p = I L I M H + V I N - V O U T L × 50 n s