SNVS589N September   2008  – November 2014 LM22671 , LM22671-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 Handling Ratings: LM22671
    3. 6.3 Handling Ratings: LM22671-Q1
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 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 Precision Enable and UVLO
      2. 7.3.2 Soft-Start
      3. 7.3.3 Switching Frequency Adjustment and Synchronization
      4. 7.3.4 Self-Synchronization
      5. 7.3.5 Boot-Strap Supply
      6. 7.3.6 Internal Loop Compensation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Current Limit
      2. 7.4.2 Thermal Shutdown
      3. 7.4.3 Duty-Cycle Limits
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Output Voltage Divider Selection
      2. 8.1.2 Power Diode
    2. 8.2 Typical Application
      1. 8.2.1 Typical Buck Regulator Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 External Components
          2. 8.2.1.2.2 Inductor
          3. 8.2.1.2.3 Input Capacitor
          4. 8.2.1.2.4 Output Capacitor
          5. 8.2.1.2.5 Boot-Strap Capacitor
        3. 8.2.1.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    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

5 Pin Configuration and Functions

HSOP Package
8-Pin
Top View
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Pin Functions

PIN TYPE DESCRIPTION APPLICATION INFORMATION
NAME NO.
BOOT 1 I Bootstrap input Provides the gate voltage for the high side NFET.
EN 5 I Precision enable pin Used to control regulator start-up and shut-down. See the Precision Enable and UVLO section of data sheet.
EP EP — Exposed Pad Connect to ground. Provides thermal connection to PCB. See the Application and Implementation.
FB 4 Feedback pin Feedback input to regulator.
GND 6 — System ground System ground pin.
RT/SYNC 3 Oscillator frequency adjust pin or frequency synchronization Used to control oscillator mode of regulator. See the Switching Frequency Adjustment and Synchronization section of data sheet.
SS 2 Soft-start pin Used to increase soft-start time. See the Soft-Start section of data sheet.
SW 8 O Switch pin Switching output of regulator.
VIN 7 I Source input voltage Supply input to the regulator.