ZHCSJ50C December   2018  – December 2022 TPS7A25

PRODUCTION DATA  

  1. 1 特性
  2. 2 应用
  3. 3 说明
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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
  7. 7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Output Enable
      2. 8.3.2 Dropout Voltage
      3. 8.3.3 Current Limit
      4. 8.3.4 Undervoltage Lockout (UVLO)
      5. 8.3.5 Thermal Shutdown
      6. 8.3.6 Power Good
      7. 8.3.7 Active Overshoot Pulldown Circuitry
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Functional Mode Comparison
      2. 8.4.2 Normal Operation
      3. 8.4.3 Dropout Operation
      4. 8.4.4 Disabled
        1.       Application and Implementation
          1. 9.1 Application Information
            1. 9.1.1 Adjustable Device Feedback Resistors
            2. 9.1.2 Recommended Capacitor Types
            3. 9.1.3 Input and Output Capacitor Requirements
            4. 9.1.4 Reverse Current
            5. 9.1.5 Feed-Forward Capacitor (CFF)
            6. 9.1.6 Power Dissipation (PD)
            7. 9.1.7 Estimating Junction Temperature
            8. 9.1.8 Special Consideration for Line Transients
          2. 9.2 Typical Application
            1. 9.2.1 Design Requirements
            2. 9.2.2 Detailed Design Procedure
              1. 9.2.2.1 Transient Response
              2. 9.2.2.2 Selecting Feedback Divider Resistors
              3. 9.2.2.3 Thermal Dissipation
            3. 9.2.3 Application Curve
          3. 9.3 Power Supply Recommendations
          4. 9.4 Layout
            1. 9.4.1 Layout Guidelines
            2. 9.4.2 Layout Examples
  9. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Device Nomenclature
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 接收文档更新通知
    4. 9.4 支持资源
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 术语表
  10. 10Mechanical, Packaging, and Orderable Information
    1. 10.1 Mechanical Data

封装选项

请参考 PDF 数据表获取器件具体的封装图。

机械数据 (封装 | 引脚)
  • DRV|6
散热焊盘机械数据 (封装 | 引脚)
订购信息

9.2.2.2 Selecting Feedback Divider Resistors

For this design example, VOUT is set to 5 V. The following equations set the feedback divider resistors for the desired output voltage:

Equation 10. VOUT = VFB × (1 + R1 / R2)
Equation 11. R1 + R2 ≤ VOUT / (IFB × 100)

For improved output accuracy, use Equation 11 and IFB(TYP) = 10 nA as listed in the Electrical Characteristics table to calculate the upper limit for series feedback resistance, R1 + R2 ≤ 5 MΩ.

The control-loop error amplifier drives the FB pin to the same voltage as the internal reference (VFB = 1.24 V as listed in the Electrical Characteristics table). Use Equation 10 to determine the ratio of R1 / R2 = 3.03. Use this ratio and solve Equation 11 for R2. Now calculate the upper limit for R2 ≤ 1.24 MΩ. Select a standard resistor value for R2 = 1.18 MΩ.

Reference Equation 10 and solve for R1:

Equation 12. R1 = (VOUT / VFB – 1) × R2

From Equation 12, R1 = 3.64 MΩ can be determined. Select a standard resistor value for R1 = 3.6 MΩ. From Equation 10, VOUT = 5.023 V.