SNVS714F April   2011  – August 2015 LM25117 , LM25117-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings (LM25117)
    3. 6.3 ESD Ratings (LM25117-Q1)
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  High Voltage Startup Regulator and VCC Disable
      2. 7.3.2  UVLO
      3. 7.3.3  Oscillator And Sync Capability
      4. 7.3.4  Ramp Generator and Emulated Current Sense
      5. 7.3.5  Error Amplifier and PWM Comparator
      6. 7.3.6  Soft-Start
      7. 7.3.7  Cycle-By-Cycle Current Limit
      8. 7.3.8  Hiccup Mode Current Limiting
      9. 7.3.9  HO and LO Drivers
      10. 7.3.10 Current Monitor
      11. 7.3.11 Maximum Duty Cycle
      12. 7.3.12 Thermal Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Diode Emulation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
    3. 8.3 Detailed Design Procedure
      1. 8.3.1  Feedback Compensation
      2. 8.3.2  Sub-Harmonic Oscillation
      3. 8.3.3  Design Requirements
      4. 8.3.4  Timing Resistor RT
      5. 8.3.5  Output Inductor LO
      6. 8.3.6  Diode Emulation Function
      7. 8.3.7  Current Sense Resistor RS
      8. 8.3.8  Current Sense Filter RCS and CCS
      9. 8.3.9  Ramp Resistor RRAMP and Ramp Capacitor CRAMP
      10. 8.3.10 UVLO Divider RUV2, RUV1 and CFT
      11. 8.3.11 VCC Disable and External VCC Supply
      12. 8.3.12 Power Switches QH and QL
      13. 8.3.13 Snubber Components RSNB and CSNB
      14. 8.3.14 Bootstrap Capacitor CHB and Bootstrap Diode DHB
      15. 8.3.15 VCC Capacitor CVCC
      16. 8.3.16 Output Capacitor CO
      17. 8.3.17 Input Capacitor CIN
      18. 8.3.18 VIN Filter RVIN, CVIN
      19. 8.3.19 Soft-Start Capacitor CSS
      20. 8.3.20 Restart Capacitor CRES
      21. 8.3.21 Output Voltage Divider RFB2 and RFB1
      22. 8.3.22 Loop Compensation Components CCOMP, RCOMP and CHF
    4. 8.4 Application Curves
      1. 8.4.1 Constant Current Regulator
      2. 8.4.2 Constant Voltage and Constant Current Regulator
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guideline
      1. 10.1.1 PC Board Layout Recommendations
  11. 11Device and Documentation Support
    1. 11.1 Community Resources
    2. 11.2 Related Links
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

4 Revision History

Changes from E Revision (March 2013) to F Revision

  • Added Device Information and Pin Configuration and Functions sections, ESD Rating table, Feature Description, Device Functional Modes, Application and Implementation, Power Supply Recommendations, Layout, Device and Documentation Support , and Mechanical, Packaging, and Orderable Information sectionsGo
  • Changed µH to µFGo

Changes from D Revision (March 2013) to E Revision

  • Changed layout of National Data Sheet to TI formatGo