ZHCSE40C August   2015  – July 2016 DRV8872

PRODUCTION DATA.  

  1. 特性
  2. 应用范围
  3. 说明
  4. 修订历史记录
  5. Pin Configuration and 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 Bridge Control
      2. 7.3.2 Sleep Mode
      3. 7.3.3 Current Regulation
      4. 7.3.4 Dead Time
      5. 7.3.5 Protection Circuits
        1. 7.3.5.1 VM Undervoltage Lockout (UVLO)
        2. 7.3.5.2 Overcurrent Protection (OCP)
        3. 7.3.5.3 Thermal Shutdown (TSD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 PWM With Current Regulation
      2. 7.4.2 PWM Without Current Regulation
      3. 7.4.3 Static Inputs With Current Regulation
      4. 7.4.4 VM Control
  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
        1. 8.2.2.1 Motor Voltage
        2. 8.2.2.2 Drive Current
        3. 8.2.2.3 Sense Resistor
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
    1. 9.1 Bulk Capacitance
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
    4. 10.4 Power Dissipation
      1. 10.4.1 Heatsinking
  11. 11器件和文档支持
    1. 11.1 文档支持
      1. 11.1.1 相关文档
    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 Glossary
  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

Power Supply Recommendations

Bulk Capacitance

Having appropriate local bulk capacitance is an important factor in motor drive system design. More bulk capacitance is generally beneficial but with the disadvantages of increased cost and physical size.

The amount of local capacitance needed depends on a variety of factors, including:

  • The highest current required by the motor system
  • The power supply’s capacitance and ability to source current
  • The amount of parasitic inductance between the power supply and motor system
  • The acceptable voltage ripple
  • The type of motor used (brushed DC, brushless DC, stepper)
  • The motor braking method

The inductance between the power supply and motor drive system limits the rate that the current can change from the power supply. If the local bulk capacitance is too small, the system responds to excessive current demands or dumps from the motor with a change in voltage. When adequate bulk capacitance is used, the motor voltage remains stable and high current can be quickly supplied.

The data sheet generally provides a recommended value, but system-level testing is required to determine the appropriate sized bulk capacitor.

DRV8872 motor_drv_sys_lvscy8.gif Figure 14. Example Setup of Motor Drive System With External Power Supply

The voltage rating for bulk capacitors should be higher than the operating voltage, to provide margin for cases when the motor transfers energy to the supply.