ZHCSKH2 November   2019 TPS7A52

ADVANCE INFORMATION for pre-production products; subject to change without notice.  

  1. 特性
  2. 应用
  3. 说明
    1.     Device Images
      1.      为射频组件供电
      2.      为数字负载供电
  4. 修订历史记录
  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
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Voltage Regulation Features
        1. 7.3.1.1 DC Regulation
        2. 7.3.1.2 AC and Transient Response
      2. 7.3.2 System Start-Up Features
        1. 7.3.2.1 Programmable Soft Start (NR/SS Pin)
        2. 7.3.2.2 Internal Sequencing
          1. 7.3.2.2.1 Enable (EN)
          2. 7.3.2.2.2 Undervoltage Lockout (UVLO) Control
          3. 7.3.2.2.3 Active Discharge
        3. 7.3.2.3 Power-Good Output (PG)
      3. 7.3.3 Internal Protection Features
        1. 7.3.3.1 Foldback Current Limit (ICL)
        2. 7.3.3.2 Thermal Protection (Tsd)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Regulation
      2. 7.4.2 Disabled
      3. 7.4.3 Current Limit Operation
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1  Recommended Capacitor Types
        1. 8.1.1.1 Input and Output Capacitor Requirements (CIN and COUT)
        2. 8.1.1.2 Noise-Reduction and Soft-Start Capacitor (CNR/SS)
        3. 8.1.1.3 Feed-Forward Capacitor (CFF)
      2. 8.1.2  Soft Start and Inrush Current
      3. 8.1.3  Optimizing Noise and PSRR
      4. 8.1.4  Charge Pump Noise
      5. 8.1.5  Current Sharing
      6. 8.1.6  Adjustable Operation
      7. 8.1.7  Power-Good Operation
      8. 8.1.8  Undervoltage Lockout (UVLO) Operation
      9. 8.1.9  Dropout Voltage (VDO)
      10. 8.1.10 Device Behavior During Transition From Dropout Into Regulation
      11. 8.1.11 Load Transient Response
      12. 8.1.12 Reverse Current Protection Considerations
      13. 8.1.13 Power Dissipation (PD)
      14. 8.1.14 Estimating Junction Temperature
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Board Layout
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 开发支持
        1. 11.1.1.1 参考设计
      2. 11.1.2 器件命名规则
    2. 11.2 文档支持
      1. 11.2.1 相关文档
    3. 11.3 接收文档更新通知
    4. 11.4 社区资源
    5. 11.5 商标
    6. 11.6 静电放电警告
    7. 11.7 Glossary
  12. 12机械、封装和可订购信息

封装选项

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

Input and Output Capacitor Requirements (CIN and COUT)

The TPS7A52 is designed and characterized for operation with ceramic capacitors of 47 µF or greater (22 µF or greater of capacitance) at the output and 10 µF or greater (5 µF or greater of capacitance) at the input. Use at least a 47-µF capacitor at the input to minimize input impedance. Place the input and output capacitors as near as practical to the respective input and output pins in order to minimize trace parasitics. If the trace inductance from the input supply to the TPS7A52 is high, a fast current transient can cause VIN to ring above the absolute maximum voltage rating and damage the device. This situation can be mitigated by additional input capacitors to dampen and keep the ringing below the device absolute maximum ratings.

A combination of multiple output capacitors boosts the high-frequency PSRR. The combination of one 0805-sized, 47-µF ceramic capacitor in parallel with two 0805-sized, 10-µF ceramic capacitors with a sufficient voltage rating, in conjunction with the PSRR boost circuit, optimizes PSRR for the frequency range of 400 kHz to 700 kHz, a typical range for dc/dc supply switching frequency. This 47-µF || 10-µF || 10-µF capacitor combination also makes certain that at high input voltage and high output voltage configurations, the minimum effective capacitance is met. Many 0805-sized, 47-µF ceramic capacitors have a voltage derating of approximately 60% to 80% at 5.0 V, so the addition of the two 10-µF capacitors makes sure that the capacitance is at or above 22 µF.