ZHCSHA0C January   2018  – September 2018 DRV10974

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     应用原理图
  4. 修订历史记录
  5. Pin Configuration and Functions
    1.     Pin Functions
  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 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Speed Input and Control
      2. 7.3.2 Motor Direction Change
      3. 7.3.3 Motor-Frequency Feedback (FG)
      4. 7.3.4 Lock Detection
        1. 7.3.4.1 Lock Kt Measure
        2. 7.3.4.2 Lock No Motor
        3. 7.3.4.3 Lock Open Loop Abnormal
        4. 7.3.4.4 Lock BEMF Abnormal
        5. 7.3.4.5 Lock Closed Loop Abnormal
        6. 7.3.4.6 Lock Speed Abnormal
      5. 7.3.5 Soft Current-Limit
      6. 7.3.6 Short-Circuit Current Protection
      7. 7.3.7 Overtemperature Protection
      8. 7.3.8 Undervoltage Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Spin-Up Settings
        1. 7.4.1.1 Motor Start
        2. 7.4.1.2 Initial Speed Detect
        3. 7.4.1.3 Align
      2. 7.4.2 Open-Loop Acceleration
      3. 7.4.3 Start-Up Current Sensing
      4. 7.4.4 Closed Loop
      5. 7.4.5 Control Advance Angle
  8. Application 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
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 第三方产品免责声明
    2. 11.2 接收文档更新通知
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 术语表
  12. 12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

Lock BEMF Abnormal

For any specific motor, the integrated value of BEMF during half of an electrical cycle is a constant as shown by the shaded gray area in Figure 11. This value is constant regardless of whether the motor runs fast or slow. The DRV10974 device monitors this value and uses it as a criterion to determine if the motor is in a lock condition.

The DRV10974 device uses the integrated BEMF to determine the Kt value of the motor during the initial motor start. Based on this measurement, a range of acceptable Kt values is established. Then, during closed-loop motor operation the Ktc (Kt calculated) value is continuously updated. Finally, the Ktc value is checked to see if it is within the range between ½ Kt and 2Kt. If the Ktc value goes beyond the acceptable range, a lock condition is triggered as shown in Figure 12. Note, there is a blanking period of 0.3 s after the transition from open loop to closed loop where the abnormal BEMF lock is momentarily disabled. The device uses this time to finalize the Kt value that Ktc is compared against.

DRV10974 figure_bemf_integration.gifFigure 11. BEMF Integration
DRV10974 g_kt_detect_slvsdn2.gifFigure 12. Abnormal Kt Lock Detect