JAJSHW2A August   2019  – April 2020 DRV425-Q1

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      概略回路図
  4. 4 改訂履歴
  5. 5 概要（続き）
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 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 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Fluxgate Sensor Front-End
        1. 8.3.1.1 Fluxgate Sensor
        2. 8.3.1.2 Bandwidth
        3. 8.3.1.3 Differential Driver for the Internal Compensation Coil
        4. 8.3.1.4 Magnetic Field Range, Overrange Indicator, and Error Flag
      2. 8.3.2 Shunt-Sense Amplifier
      3. 8.3.3 Voltage Reference
      4. 8.3.4 Low-Power Operation
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Linear Position Sensing
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Current Sensing in Busbars
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Power Supply Decoupling
    2. 10.2 Power-On Start-Up and Brownout
    3. 10.3 Power Dissipation
      1. 10.3.1 Thermal Pad
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 ドキュメントのサポート
      1. 12.1.1 関連資料
    2. 12.2 ドキュメントの更新通知を受け取る方法
    3. 12.3 サポート・リソース
    4. 12.4 商標
    5. 12.5 静電気放電に関する注意事項
    6. 12.6 Glossary
  13. 13メカニカル、パッケージ、および注文情報

9.2.2.1 Design Requirements

In order to measure the field gradient in the busbar, two DRV425-Q1 sensors are placed inside the hole at a well-defined distance by mounting them on opposite sides of a PCB that is inserted in the hole.  The measurement range and resolution of this solution depends on the following factors:

  • Busbar geometry: a wider busbar means a larger measurement range and lower resolution.
  • Size of the hole: a larger diameter means a larger measurement range and lower resolution.
  • Distance between the two DRV425-Q1 sensors: a smaller distance increases the measurement range and resolution.

Each of these factors can be optimized to create the desired measurement range for a particular application. Measurement ranges of ±250 A to ±1500 A are achievable with this approach. Larger currents are supported with large busbar structures and minimized distance between the two DRV425-Q1 sensors. Use the parameters listed in Table 3 as a starting point of the design.

Table 3. Design Parameters

DESIGN PARAMETER EXAMPLE VALUE
Current range Up to ±1500 A
Supply voltage, VDD 3.0 V to 5.5 V
Reference voltage, VREFIN VDD / 2