SNVSAC2A March   2015  – June 2020 LM317A

PRODUCTION DATA.  

  1. Features
  2. Applications
    1.     Typical Application
  3. Description
    1.     Revision History
  4. Device Comparison Table
  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 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Load Regulation
    4. 7.4 Device Functional Modes
      1. 7.4.1 External Capacitors
      2. 7.4.2 Protection Diodes
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1  1.25-V to 25-V Adjustable Regulator
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2  5-V Logic Regulator With Electronic Shutdown
      3. 8.2.3  Slow Turnon 15-V Regulator
      4. 8.2.4  Adjustable Regulator With Improved Ripple Rejection
      5. 8.2.5  High-Stability 10-V Regulator
      6. 8.2.6  High-Current Adjustable Regulator
      7. 8.2.7  Emitter-Follower Current Amplifier
      8. 8.2.8  1-A Current Regulator
      9. 8.2.9  Common-Emitter Amplifier
      10. 8.2.10 Low-Cost 3-A Switching Regulator
      11. 8.2.11 Current-Limited Voltage Regulator
      12. 8.2.12 Adjusting Multiple On-Card Regulators With Single Control
      13. 8.2.13 AC Voltage Regulator
      14. 8.2.14 12-V Battery Charger
      15. 8.2.15 Adjustable 4-A Regulator
      16. 8.2.16 Current-Limited 6-V Charger
      17. 8.2.17 Digitally-Selected Outputs
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Thermal Considerations
        1. 10.1.1.1 Heatsink Requirements
        2. 10.1.1.2 Heatsinking Surface Mount Packages
          1. 10.1.1.2.1 Heatsinking the SOT-223 (DCY) Package
          2. 10.1.1.2.2 Heatsinking the TO-252 (NDP) Package
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

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机械数据 (封装 | 引脚)
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订购信息

1.25-V to 25-V Adjustable Regulator

The LM317A can be used as a simple, low-dropout regulator to enable a variety of output voltages needed for demanding applications. By using an adjustable R2 resistor, a variety of output voltages can be made possible as shown in Figure 18.

LM317A 906301.gif

NOTE:

Full output current not available at high input-output voltages
*Needed if device is more than 6 inches from filter capacitors.
†Optional—improves transient response. Output capacitors in the range of 1 μF to 1000 μF of aluminum or tantalum electrolytic are commonly used to provide improved output impedance and rejection of transients.
LM317A 906349.gif
Figure 18. 1.25-V to 25-V Adjustable Regulator