SNVS584P September   2008  – November 2014 LM22670 , LM22670-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: LM22670
    3. 6.3 Handling Ratings: LM22670-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 Shutdown Mode
      2. 7.4.2 Active Mode
      3. 7.4.3 Current Limit
      4. 7.4.4 Thermal Protection
      5. 7.4.5 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 Examples
    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
LM22670 LM22670-Q1 30076040.gif
TO-263 Package
7-Pin
Top View
LM22670 LM22670-Q1 30076002.gif

Pin Functions

PIN TYPE DESCRIPTION APPLICATION INFORMATION
NAME SO PowerPAD-8 Package PFM Package
BOOT 1 3 I Bootstrap input Provides the gate voltage for the high side NFET.
NC 2 — — Not Connected Pin is not electrically connected inside the chip. Pin does function as thermal conductor.
RT/SYNC 3 5 I Oscillator mode control input Used to control oscillator mode of regulator. See Switching Frequency Adjustment and Synchronization and Self-Synchronization of data sheet.
FB 4 6 I Feedback input Feedback input to regulator.
EN 5 7 I Enable input Used to control regulator start-up and shut-down. See Precision Enable and UVLO of data sheet.
GND 6 4 — Ground input to regulator;
system common		 System ground pin.
VIN 7 2 I Input voltage Supply input to the regulator.
SW 8 1 O Switch output Switching output of regulator.
EP EP EP — Exposed Pad Connect to ground. Provides thermal connection to PCB. See Application and Implementation.