JAJSQ94D January   2019  – June 2024 UCC21710-Q1

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Power Ratings
    6. 5.6  Insulation Specifications
    7. 5.7  Safety-Related Certifications
    8. 5.8  Safety Limiting Values
    9. 5.9  Electrical Characteristics
    10. 5.10 Switching Characteristics
    11. 5.11 Insulation Characteristics Curves
    12. 5.12 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Propagation Delay
      1. 6.1.1 Regular Turn-OFF
    2. 6.2 Input Deglitch Filter
    3. 6.3 Active Miller Clamp
      1. 6.3.1 Internal On-chip Active Miller Clamp
    4. 6.4 Under Voltage Lockout (UVLO)
      1. 6.4.1 VCC UVLO
      2. 6.4.2 VDD UVLO
    5. 6.5 OC (Over Current) Protection
      1. 6.5.1 OC Protection with Soft Turn-OFF
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power Supply
      2. 7.3.2  Driver Stage
      3. 7.3.3  VCC and VDD Undervoltage Lockout (UVLO)
      4. 7.3.4  Active Pulldown
      5. 7.3.5  Short Circuit Clamping
      6. 7.3.6  Internal Active Miller Clamp
      7. 7.3.7  Overcurrent and Short Circuit Protection
      8. 7.3.8  Soft Turn-off
      9. 7.3.9  Fault ( FLT, Reset and Enable ( RST/EN)
      10. 7.3.10 Isolated Analog to PWM Signal Function
    4. 7.4 Device Functional Modes
  9. 8 Applications and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Input filters for IN+, IN- and RST/EN
        2. 8.2.2.2 PWM Interlock of IN+ and IN-
        3. 8.2.2.3 FLT, RDY and RST/EN Pin Circuitry
        4. 8.2.2.4 RST/EN Pin Control
        5. 8.2.2.5 Turn on and turn off gate resistors
        6. 8.2.2.6 Overcurrent and Short Circuit Protection
          1. 8.2.2.6.1 Protection Based on Power Modules with Integrated SenseFET
          2. 8.2.2.6.2 Protection Based on Desaturation Circuit
          3. 8.2.2.6.3 Protection Based on Shunt Resistor in Power Loop
        7. 8.2.2.7 Isolated Analog Signal Sensing
          1. 8.2.2.7.1 Isolated Temperature Sensing
          2. 8.2.2.7.2 Isolated DC Bus Voltage Sensing
        8. 8.2.2.8 Higher Output Current Using an External Current Buffer
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 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. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

8.2.2.4 RST/EN Pin Control

RST/EN pin has two functions. It is used to enable or shutdown the outputs of the driver and to reset the fault signaled on the FLT pin after OC is detected. RST/EN pin needs to be pulled up to enable the device; when the pin is pulled down, the device is in disabled status. By default the driver is disabled with the internal 50kΩ pulldown resistor at this pin.

When the driver is latched after overcurrent or short circuit fault is detected, the FLT pin and output are latched low and need to be reset by the RST/EN pin. The microcontroller must send a signal to RST/EN pin after the fault to reset the driver. The driver will not respond until after the mute time tFLTMUTE. The reset signal must be held low for at least tRSTFIL after the mute time.

This pin can also be used to automatically reset the driver. The continuous input signal IN+ or IN- can be applied to RST/EN pin. There is no separate reset signal from the microcontroller when configuring the driver this way. If the PWM is applied to the non-inverting input IN+, then IN+ can also be tied to RST/EN pin. If the PWM is applied to the inverting input IN-, then a NOT logic is needed between the PWM signal from the microcontroller and the RST/EN pin. Using either configuration results in the driver being reset in every switching cycle without an extra control signal from microcontroller tied to RST/EN pin. One must ensure the PWM off-time is greater than tRSTFIL in order to reset the driver in cause of a OC fault.

UCC21710-Q1 Automatic Reset ControlFigure 8-4 Automatic Reset Control