JAJSPK3G May   2001  – December 2022 BQ2057C

PRODUCTION DATA  

  1. 特長
  2. アプリケーション
  3. 概要
  4. Revision History
  5. 概要 (続き)
  6. Device Comparison Table
  7. Pin Configuration and Functions
  8. Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Typical Characteristics
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Current-Sense Input
      2. 9.3.2 Battery-Voltage Input
      3. 9.3.3 Temperature Sense Input
      4. 9.3.4 Charge-status Output
      5. 9.3.5 Charge-Control Output
      6. 9.3.6 Charge-Rate Compensation Input
      7. 9.3.7 Supply Voltage Input
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1  Functional Description
      2. 10.1.2  Qualification and Precharge
      3. 10.1.3  Current Regulation Phase
      4. 10.1.4  Voltage Regulation Phase
      5. 10.1.5  Charge Termination and Recharge
      6. 10.1.6  Battery Temperature Monitoring
      7. 10.1.7  Charge Inhibit Function
      8. 10.1.8  Charge Status Indication
      9. 10.1.9  Low-power Sleep Mode
      10. 10.1.10 Selecting an External Pass-Transistor
      11. 10.1.11 Selecting Input Capacitor
      12. 10.1.12 Selecting Output Capacitor
      13. 10.1.13 Automatic Charge-rate Compensation
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Power FET
      2. 12.1.2 Current Sense
      3. 12.1.3 Voltage Sense
      4. 12.1.4 Enable (TS)
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 サード・パーティ製品に関する免責事項
    2. 13.2 ドキュメントの更新通知を受け取る方法
    3. 13.3 サポート・リソース
    4. 13.4 Trademarks
    5. 13.5 静電気放電に関する注意事項
    6. 13.6 用語集
  14. 14Mechanical, Packaging, and Orderable Information

パッケージ・オプション

デバイスごとのパッケージ図は、PDF版データシートをご参照ください。

メカニカル・データ(パッケージ|ピン)
  • D|8
  • DGK|8
  • PW|8
サーマルパッド・メカニカル・データ
発注情報

Current Regulation Phase

The BQ2057 regulates current while the battery-pack voltage is less than the regulation voltage, VO(REG). The BQ2057 monitors charge current at the SNS input by the voltage drop across a sense-resistor, RSNS, in series with the battery pack. In high-side current sensing configuration (see Figure 10-5), RSNS is between the VCC and SNS pins, and in low-side sensing (see Figure 10-6) the RSNS is between VSS (battery negative) and SNS (charger ground) pins. Charge-current feedback, applied through pin SNS, maintains a voltage of V(SNS) across the current sense resistor. Equation 1 calculates the value of the sense resistor:

Equation 1. GUID-1D5D6AFE-C93B-47B1-9CAA-F9C578F9561C-low.gif

Where IO(REG) is the desired charging current.

GUID-20220527-SS0I-4NWW-QTJV-MMNZC2NDQBQ5-low.gifFigure 10-5 High-Side Current Sensing
GUID-20220527-SS0I-FFGK-QVDS-XLDJBDV0VJFM-low.gifFigure 10-6 Low-Side Current Sensing