SNVSCF2A November   2025  – May 2026 LM65680

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Related Products
  6. 5 Pin Configuration and Functions
    1. 5.1 Wettable Flanks
    2. 5.2 Pinout Design for Clearance and FMEA
  7. 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
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Descriptions
      1. 7.3.1  Input Voltage Range (VIN1, VIN2)
      2. 7.3.2  High-Voltage Bias Supply Subregulator (VCC, BIAS)
      3. 7.3.3  Precision Enable and Adjustable Input Voltage UVLO (EN/UVLO)
      4. 7.3.4  Output Voltage Setpoint (FB, BIAS)
      5. 7.3.5  Switching Frequency (RT)
      6. 7.3.6  Mode Selection and Clock Synchronization (MODE/SYNC)
        1. 7.3.6.1 Clock Synchronization
        2. 7.3.6.2 Clock Locking
      7. 7.3.7  Device Configuration (CNFG/SYNCOUT)
      8. 7.3.8  Dual-Random Spread Spectrum (DRSS)
      9. 7.3.9  High-Side MOSFET Gate Drive (BST)
      10. 7.3.10 Configurable Soft Start (SS)
        1. 7.3.10.1 Recovery From Dropout
      11. 7.3.11 Protection Features
        1. 7.3.11.1 Power-Good Monitor (PG)
        2. 7.3.11.2 Overcurrent and Short-Circuit Protection
        3. 7.3.11.3 Hiccup-Mode Protection
        4. 7.3.11.4 Thermal Shutdown
      12. 7.3.12 Two-Phase, Single-Output Operation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Active Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Power Train Components
        1. 8.1.1.1 Buck Inductor
        2. 8.1.1.2 Output Capacitors
        3. 8.1.1.3 Input Capacitors
        4. 8.1.1.4 EMI Filter
      2. 8.1.2 Error Amplifier and Compensation
      3. 8.1.3 Maximum Ambient Temperature
        1. 8.1.3.1 Derating Curves
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1 – 5V, 8A Synchronous Buck Regulator With Wide Input Voltage Range and High Efficiency
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2  Choosing the Switching Frequency
          3. 8.2.1.2.3  Buck Inductor Selection
          4. 8.2.1.2.4  Input Capacitor Selection
          5. 8.2.1.2.5  Output Capacitors
          6. 8.2.1.2.6  Output Voltage Setpoint
          7. 8.2.1.2.7  Compensation Components
          8. 8.2.1.2.8  Setting the Input Voltage UVLO
          9. 8.2.1.2.9  EMI Mitigation, RDRSS
          10. 8.2.1.2.10 Bootstrap Capacitor, CBST
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Design 2 – High Efficiency, 48V to 12V, 8A, 400kHz Synchronous Buck Regulator
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Buck Inductor Selection
          2. 8.2.2.2.2 Input Capacitor Selection
          3. 8.2.2.2.3 Output Capacitors
          4. 8.2.2.2.4 Output Voltage Setpoint
          5. 8.2.2.2.5 Compensation Components
          6. 8.2.2.2.6 Feedforward Capacitor
          7. 8.2.2.2.7 Soft-Start Capacitor
        3. 8.2.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
        1. 8.5.1.1 Thermal Design and Layout
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
      2. 9.1.2 Development Support
        1. 9.1.2.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
        1. 9.2.1.1 Low-EMI Design Resources
        2. 9.2.1.2 Thermal Design Resources
        3. 9.2.1.3 Multiphase Design Resources
        4. 9.2.1.4 PCB Layout Resources
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

5.1 Wettable Flanks

100% automated visual inspection (AVI) post-assembly is typically required to meet requirements for high reliability and robustness. Standard quad-flat no-lead (QFN) packages do not have solderable or exposed pins and terminals that are easily viewed. Visually determining whether or not the package is successfully soldered onto the printed-circuit board (PCB) is therefore difficult. The wettable-flank process is developed to resolve the issue of side-lead wetting of leadless packaging. The LM656x0 is assembled using a 26-pin Enhanced HotRod WQFN package with dimple wettable flanks that allow side-lead solder inspection during manufacturing. This visual indicator of solderability reduces inspection time and manufacturing costs.