SNAS714C November   2016  – August 2021 LMS3635-Q1 , LMS3655-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Tables
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Thermal Information (for Device Mounted on PCB)
    6. 7.6 Electrical Characteristics
    7. 7.7 System Characteristics
    8. 7.8 Timing Requirements
    9. 7.9 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
      1. 8.2.1 Control Scheme
    3. 8.3 Feature Description
      1. 8.3.1 RESET Flag Output
      2. 8.3.2 Enable and Start-Up
      3. 8.3.3 Soft-Start Function
      4. 8.3.4 Current Limit
      5. 8.3.5 Hiccup Mode
      6. 8.3.6 Synchronizing Input
      7. 8.3.7 Undervoltage Lockout (UVLO) and Thermal Shutdown (TSD)
      8. 8.3.8 Input Supply Current
    4. 8.4 Device Functional Modes
      1. 8.4.1 AUTO Mode
      2. 8.4.2 FPWM Mode
      3. 8.4.3 Dropout
      4. 8.4.4 Spread-Spectrum Operation
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 General Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 9.2.1.2.2 External Components Selection
            1. 9.2.1.2.2.1 Input Capacitors
            2. 9.2.1.2.2.2 Output Inductors and Capacitors
              1. 9.2.1.2.2.2.1 Inductor Selection
              2. 9.2.1.2.2.2.2 Output Capacitor Selection
          3. 9.2.1.2.3 Setting the Output Voltage
          4. 9.2.1.2.4 FB for Adjustable Output
          5. 9.2.1.2.5 VCC
          6. 9.2.1.2.6 BIAS
          7. 9.2.1.2.7 CBOOT
          8. 9.2.1.2.8 Maximum Ambient Temperature
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Fixed 5-V Output for USB-Type Applications
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
      3. 9.2.3 Fixed 3.3-V Output
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
        3. 9.2.3.3 Application Curves
      4. 9.2.4 6-V Adjustable Output
        1. 9.2.4.1 Design Requirements
        2. 9.2.4.2 Detailed Design Procedure
        3. 9.2.4.3 Application Curves
    3. 9.3 Do's and Don't's
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
      2. 12.1.2 Development Support
        1. 12.1.2.1 Custom Design With WEBENCH® Tools
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

7.5 Thermal Information (for Device Mounted on PCB)

THERMAL METRIC(1)LMS36x5-Q1UNIT
RNL (VQFN)
22 PINS
RθJAJunction-to-ambient thermal resistance29.4°C/W
RθJCJunction-to-case (top) thermal resistance14.2°C/W
RθJBJunction-to-board thermal resistance5.4°C/W
ψJTJunction-to-top characterization parameter1.2°C/W
ψJBJunction-to-board characterization parameter5.4°C/W
RθJC(bot)Junction-to-case (bottom) thermal resistance2.4°C/W
(1) Mounted on a thermally optimized FR4 four layer EVM with a size of 4000 mill × 3000 mill.