ZHCSBE5D August   2013  – June 2025 TPS62090-Q1

PRODUCTION DATA  

  1.   1
  2. 1 特性
  3. 2 应用
  4. 3 说明
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Enable and Disable (EN)
      2. 6.3.2  Soft Start (SS) and Hiccup Current Limit During Start-Up
      3. 6.3.3  Voltage Tracking (SS)
      4. 6.3.4  Short-Circuit Protection (Hiccup Mode)
      5. 6.3.5  Output Discharge Function
      6. 6.3.6  Power Good Output (PG)
      7. 6.3.7  Frequency Set Pin (FREQ)
      8. 6.3.8  Undervoltage Lockout (UVLO)
      9. 6.3.9  Thermal Shutdown
      10. 6.3.10 Charge Pump (CP, CN)
    4. 6.4 Device Functional Modes
      1. 6.4.1 Pulse Width Modulation Operation
      2. 6.4.2 Power Save Mode Operation
      3. 6.4.3 Low-Dropout Operation (100% Duty Cycle)
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Inductor Selection
        2. 7.2.2.2 Input and Output Capacitor Selection
        3. 7.2.2.3 Setting the Output Voltage
      3. 7.2.3 Application Curves
    3. 7.3 System Examples
    4. 7.4 Power Supply Recommendations
    5. 7.5 Layout
      1. 7.5.1 Layout Guidelines
      2. 7.5.2 Layout Example
  9. 8 器件和文档支持
    1. 8.1 器件支持
      1. 8.1.1 第三方产品免责声明
    2. 8.2 文档支持
      1. 8.2.1 相关文档
    3. 8.3 接收文档更新通知
    4. 8.4 支持资源
    5. 8.5 商标
    6. 8.6 静电放电警告
    7. 8.7 术语表
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.2.2.1 Inductor Selection

The inductor selection is affected by several parameters such as inductor-ripple current, output-voltage ripple, transition point into power save mode, and efficiency. See Table 7-4 for typical inductors.

Table 7-4 Inductor Selection
INDUCTOR VALUECOMPONENT SUPPLIERSIZE (L × W × H mm)Isat / DCR
0.6 µHCoilcraft XAL4012-6014 × 4 × 2.17.1 A / 9.5 mΩ
1 µHCoilcraft XAL4020-1024 × 4 × 2.15.9 A / 13.2 mΩ
1 µHCoilcraft XFL4020-1024 × 4 × 2.15.1 A / 10.8 mΩ
0.47 µHTOKO DFE252012 R472.5 × 2 × 1.23.7 A / 39 mΩ
1 µHTOKO DFE252012 1R02.5 × 2 × 1.23.0 A / 59 mΩ
0.68 µHTOKO DFE322512 R683.2 × 2.5 × 1.23.5 A / 37 mΩ
1 µHTOKO DFE322512 1R03.2 × 2.5 × 1.23.1 A / 45 mΩ

In addition, the inductor must be rated for the appropriate saturation current and DC resistance (DCR). The inductor must be rated for a saturation current as high as the typical switch current limit, of 4.6 A or according to Equation 5 and Equation 6. Equation 5 and Equation 6 calculate the maximum inductor current under static load conditions. The formula takes the converter efficiency into account. The converter efficiency is taken from the Section 5.6 graphs or 80% can be used as a conservative approach. The calculation must be done for the maximum input voltage where the peak switch current is highest.

Equation 5. TPS62090-Q1
Equation 6. TPS62090-Q1

where

  • ƒ = Converter switching frequency (typical 2.8 MHz or 1.4 MHz)
  • L = Selected inductor value
  • η = Estimated converter efficiency (use the number from the efficiency curves or 0.80 as an conservative assumption)
Note:

The calculation must be done for the maximum input voltage of the application

Calculating the maximum inductor current using the actual operating conditions gives the minimum saturation current. A margin of 20% must be added to cover for load transients during operation.