JAJSB44G October   2011  – July 2018 LMZ10500

PRODUCTION DATA.  

  1. 特長
  2. アプリケーション
  3. 概要
    1.     Device Images
      1.      VIN = 3.6Vでの標準的な効率
      2.      放射EMI (CISPR22) VIN = 5V、VOUT = 1.8V、IOUT = 650mA
  4. 改訂履歴
  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 System Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Current Limit
      2. 7.3.2 Start-up Behavior and Soft Start
      3. 7.3.3 Output Short Circuit Protection
      4. 7.3.4 Thermal Overload Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Circuit Operation
      2. 7.4.2 Input Undervoltage Detection
      3. 7.4.3 Shutdown Mode
      4. 7.4.4 EN Pin Operation
      5. 7.4.5 Internal Synchronous Rectification
      6. 7.4.6 High Duty Cycle Operation
  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 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Setting the Output Voltage
          1. 8.2.2.2.1 RT and RB Selection for Fixed VOUT
          2. 8.2.2.2.2 Output Voltage Accuracy Optimization
        3. 8.2.2.3 Dynamic Output Voltage Scaling
        4. 8.2.2.4 Integrated Inductor
        5. 8.2.2.5 Input and Output Capacitor Selection
      3. 8.2.3 Application Curves
        1. 8.2.3.1 VOUT = 1.2 V
        2. 8.2.3.2 VOUT = 1.8 V
        3. 8.2.3.3 VOUT = 2.5 V
        4. 8.2.3.4 VOUT = 3.3 V
  9. Power Supply Recommendations
    1. 9.1 Voltage Range
    2. 9.2 Current Capability
    3. 9.3 Input Connection
      1. 9.3.1 Voltage Drops
      2. 9.3.2 Stability
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Package Considerations
  11. 11デバイスおよびドキュメントのサポート
    1. 11.1 デバイス・サポート
      1. 11.1.1 WEBENCH®ツールによるカスタム設計
    2. 11.2 ドキュメントのサポート
    3. 11.3 ドキュメントの更新通知を受け取る方法
    4. 11.4 コミュニティ・リソース
    5. 11.5 商標
    6. 11.6 静電気放電に関する注意事項
    7. 11.7 Glossary
  12. 12メカニカル、パッケージ、および注文情報

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)
  • SIL|8
発注情報

Stability

The added inductance of long input cables together with the ceramic (and low ESR) input capacitor can result in an under damped RLC network at the input of the Buck converter. This can cause oscillations on the input and instability. If long wires are used, it is recommended to add some electrolytic capacitance in parallel with the ceramic input capacitor. The electrolytic capacitor's ESR will improve the damping.

Use an electrolytic capacitor with CELECTROLYTIC≥ 4 × CCERAMIC and ESRELECTROLYTIC≈ √ (LCABLE / CCERAMIC)

For example, two cables (one for VIN and one for GND), each 1 meter (~3 ft) long with ~1 mm diameter (18AWG), placed 1 cm (~0.4 in) apart will form a rectangular loop resulting in about 1.2 µH of inductance. The inductance in this example can be decreased to almost half if the input wires are twisted. Based on a 10-µF ceramic input capacitor, the recommended parallel CELECTROLYTIC is ≥ 40 µF. Using a 47-µF capacitor will be sufficient. The recommended ESRELECTROLYTIC≈ 0.35 Ω or larger, based on about 1.2 µH of inductance and 10 µF of ceramic input capacitance.

See application note SNVA489 for more details on input filter design.