JAJSHJ3D June   2019  – March 2020 TPS62840

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      代表的なアプリケーション
      2.      効率と負荷電流の関係 (VOUT = 1.8V)
  4. 4 改訂履歴
  5. 5 Device Comparison Table
  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 Smart Enable and Shutdown
      2. 8.3.2 Soft Start
      3. 8.3.3 Mode Selection: Power-Save Mode (PFM/PWM) or Forced PWM Operation (FPWM)
      4. 8.3.4 Output Voltage Selection (VSET)
      5. 8.3.5 Undervoltage Lockout UVLO
      6. 8.3.6 Switch Current Limit / Short Circuit Protection
      7. 8.3.7 Output Voltage Discharge
      8. 8.3.8 Thermal Shutdown
      9. 8.3.9 STOP Mode
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Save Mode Operation
      2. 8.4.2 Forced PWM Mode Operation
      3. 8.4.3 100% Mode Operation
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Inductor Selection
        2. 9.2.2.2 Output Capacitor Selection
        3. 9.2.2.3 Input Capacitor Selection
      3. 9.2.3 Application Curves
    3. 9.3 System Example
  10. 10Power Supply Recommendations
  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 デバイス・サポート
      1. 12.1.1 デベロッパー・ネットワークの製品に関する免責事項
    2. 12.2 サポート・リソース
    3. 12.3 商標
    4. 12.4 静電気放電に関する注意事項
    5. 12.5 Glossary
  13. 13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

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

9.2.2.1 Inductor Selection

The inductor value affects the peak-to-peak ripple current, PWM-to-PFM transition point, output voltage ripple, and efficiency. The selected inductor has to be rated for its DC resistance and saturation current. The inductor ripple current (ΔIL) decreases with higher inductance and increases with higher VIN or VOUT and can be estimated according to Equation 4.

Equation 5 calculates the maximum inductor current under static load conditions. The saturation current of the inductor must be rated higher than the maximum inductor current, as calculated with Equation 5. This is recommended because during a heavy load transient the inductor current rises above the calculated value. A more conservative way is to select the inductor saturation current according to the high-side MOSFET switch current limit, ILIMF.

Equation 4. TPS62840 eq4_dil_lvs941.gif
Equation 5. TPS62840 eq5_ilmax_lvs941.gif

where

  • f is the switching frequency
  • L is the inductance
  • ΔIL is the peak-to-peak inductor ripple current
  • ILmax is the maximum inductor current

Table 4 shows a list of possible inductors.

Table 4. List of Possible Inductors(1)

INDUCTANCE [µH] INDUCTOR TYPE SIZE [L x W x T] SUPPLIER
2.2 DFE201612E [2.0 mm x 1.6 mm x 1.2 mm max.] muRata
2.2 DFE201210S [2.0 mm x 1.2 mm x 1.0 mm max.] muRata