SNVS178H January   2002  – December 2015 LM3485

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
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 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 Hysteretic Control Circuit
      2. 7.3.2 Current Limit Operation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Start Up
      2. 7.4.2 External Sense Resistor
      3. 7.4.3 PGATE
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Step by Step Design Procedure
        2. 8.2.2.2 Inductor Selection (L1)
        3. 8.2.2.3 Output Voltage Set Point
        4. 8.2.2.4 Output Capacitor Selection (COUT)
        5. 8.2.2.5 Input Capacitor Selection (CIN)
        6. 8.2.2.6 Programming the Current Limit (RADJ)
        7. 8.2.2.7 Catch Diode Selection (D1)
        8. 8.2.2.8 P-Channel MOSFET Selection (Q1)
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Community Resources
    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

9 Power Supply Recommendations

The devices are designed to generate from an input voltage supply range between 4.5 V and 35 V. The input should be well regulated. If the input supply is located more than a few inches from the LM3485 EVM, an additional bulk capacitor may be required. A tantalum capacitor with a valve of 47 µt as a typical choice.