SNVS120G April   2000  – May 2019 LM2585

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      12-V Flyback Regulator Design Example
  4. Revision History
  5. Pin Configurations
  6. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Ratings
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics: 3.3 V
    6. 6.6  Electrical Characteristics: 5 V
    7. 6.7  Electrical Characteristics: 12-V
    8. 6.8  Electrical Characteristics: Adjustable
    9. 6.9  Electrical Characteristics: All Versions
    10. 6.10 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Step-Up (Boost) Regulator Operation
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Boost Regulator Applications
      2. 8.2.2 Typical Flyback Regulator Applications
        1. 8.2.2.1 Transformer Selection (T)
        2. 8.2.2.2 Transformer Footprints
          1. 8.2.2.2.0.1 T6
          2. 8.2.2.2.0.2 T6
      3. 8.2.3 Design Requirements
      4. 8.2.4 Detailed Design Procedure
        1. 8.2.4.1 Custom Design With WEBENCH® Tools
        2. 8.2.4.2 Programming Output Voltage (Selecting R1 And R2)
        3. 8.2.4.3 Short Circuit Condition
        4. 8.2.4.4 Flyback Regulator Input Capacitors
        5. 8.2.4.5 Switch Voltage Limits
        6. 8.2.4.6 Output Voltage Limitations
        7. 8.2.4.7 Noisy Input Line Condition
        8. 8.2.4.8 Stability
      5. 8.2.5 Application Curve
    3. 8.3 Additional Application Examples
      1. 8.3.1 Test Circuits
  9. Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Heat Sink/Thermal Considerations
  10. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
      2. 10.1.2 Development Support
        1. 10.1.2.1 Custom Design With WEBENCH® Tools
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Community Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Test Circuits

LM2585 1251519.png
CIN1—100 μF, 25V Aluminum Electrolytic

CIN2—0.1 μF Ceramic

T—22 μH, 1:1 Schott #67141450

D—1N5820

COUT—680 μF, 16V Aluminum Electrolytic

CC—0.47 μF Ceramic

RC—2k
Figure 47. Lm2585-3.3 And Lm2585-5.0
LM2585 1251520.png
CIN1—100 μF, 25V Aluminum Electrolytic

CIN2—0.1 μF Ceramic

L—15 μH, Renco #RL-5472-5

D—1N5820

COUT—680 μF, 16V Aluminum Electrolytic

CC—0.47 μF Ceramic

RC—2k

For 12V Devices: R1 = Short (0Ω) and R2 = Open

For ADJ Devices: R1 = 48.75k, ±0.1% and R2 = 5.62k, ±1%
Figure 48. Lm2585-12 And Lm2585-Adj
LM2585 1251501.pngFigure 49. Flyback Regulator
LM2585 1251555.pngFigure 50. Boost Regulator