ZHCSKC0 October   2019 UCC21736-Q1

ADVANCE INFORMATION for pre-production products; subject to change without notice.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     器件引脚配置
  4. 4 修订历史记录
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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  Power Ratings
    6. 6.6  Electrical Characteristics
    7. 6.7  Switching Characteristics
    8. 6.8  Insulation Specifications
    9. 6.9  Safety-Related Certifications
    10. 6.10 Safety Limiting Values
    11. 6.11 Insulation Characteristics Curves
    12. 6.12 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Propagation Delay
      1. 7.1.1 Regular Turn-OFF
    2. 7.2 Input Deglitch Filter
    3. 7.3 Active Miller Clamp
      1. 7.3.1 External Active Miller Clamp
    4. 7.4 Under Voltage Lockout (UVLO)
      1. 7.4.1 VCC UVLO
      2. 7.4.2 VDD UVLO
      3. 7.4.3 VEE UVLO
    5. 7.5 OC (Over Current) Protection
      1. 7.5.1 OC Protection with Soft Turn-OFF
    6. 7.6 ASC Protection
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power Supply
      2. 8.3.2 Driver Stage
      3. 8.3.3 VCC, VDD and VEE Undervoltage Lockout (UVLO)
      4. 8.3.4 Active Pulldown
      5. 8.3.5 Short Circuit Clamping
      6. 8.3.6 External Active Miller Clamp
      7. 8.3.7 Overcurrent and Short Circuit Protection
      8. 8.3.8 Fault (FLT, Reset and Enable (RST/EN)
      9. 8.3.9 ASC Protection and APWM Monitor
    4. 8.4 Device Functional Modes
  9. 9 Applications 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 Input filters for IN+, IN- and RST/EN
        2. 9.2.2.2 PWM Interlock of IN+ and IN-
        3. 9.2.2.3 FLT, RDY and RST/EN Pin Circuitry
        4. 9.2.2.4 RST/EN Pin Control
        5. 9.2.2.5 Turn on and turn off gate resistors
        6. 9.2.2.6 External Active Miller Clamp
        7. 9.2.2.7 Overcurrent and Short Circuit Protection
          1. 9.2.2.7.1 Protection Based on Power Modules with Integrated SenseFET
          2. 9.2.2.7.2 Protection Based on Desaturation Circuit
          3. 9.2.2.7.3 Protection Based on Shunt Resistor in Power Loop
        8. 9.2.2.8 Higher Output Current Using an External Current Buffer
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12器件和文档支持
    1. 12.1 文档支持
      1. 12.1.1 相关文档
    2. 12.2 接收文档更新通知
    3. 12.3 社区资源
    4. 12.4 商标
    5. 12.5 静电放电警告
    6. 12.6 Glossary
  13. 13机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

8.3.6 External Active Miller Clamp

Active miller clamp feature is important to prevent the false turn-on while the driver is in OFF state. In applications which the device can be in synchronous rectifier mode, the body diode conducts the current during the deadtime while the device is in OFF state, the drain-source or collector-emitter voltage remains the same and the dV/dt happens when the other power semiconductor of the phase leg turns on. The low internal pull-down impedance of UCC21736-Q1 can provide a strong pulldown to hold the OUTL to VEE. However, external gate resistance is usually adopted to limit the dV/dt. The miller effect during the turn on transient of the other power semiconductor can cause a voltage drop on the external gate resistor, which boost the gate-source or gate-emitter voltage. If the voltage on VGS or VGE is higher than the threshold voltage of the power semiconductor, a shoot through can happen and cause catastrophic damage. The active miller clamp feature of UCC21736-Q1 drives an external MOSFET, which connects to the device gate. The external MOSFET is triggered when the gate voltage is lower than VCLMPTH, which is 2V above VEE, and creates a low impedance path to avoid the false turn on issue.

UCC21736-Q1 CLMPI-BLOCK.gifFigure 42. Active Miller Clamp