SNVS007H september   1998  – june 2023 LM2676

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Description (continued)
  7. 6 Pin Configuration and Functions
  8. 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  Electrical Characteristics – 3.3-V Version
    6. 7.6  Electrical Characteristics – 5-V Version
    7. 7.7  Electrical Characteristics – 12-V Version
    8. 7.8  Electrical Characteristics – Adjustable Voltage Version
    9. 7.9  Electrical Characteristics – All Output Voltage Versions
    10. 7.10 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Adjustable Output Voltage
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode
      2. 8.4.2 Active Mode
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Fixed Output Voltage Typical 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 Inductor Selection (L1)
          3. 9.2.1.2.3 Output Capacitor Selection (COUT)
          4. 9.2.1.2.4 Catch Diode Selection (D1)
          5. 9.2.1.2.5 Input Capacitor (CIN)
          6. 9.2.1.2.6 Boost Capacitor (CB)
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Adjustable Output Voltage Typical Application
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Programming Output Voltage
          2. 9.2.2.2.2 Inductor Selection (L1)
          3. 9.2.2.2.3 Output Capacitor Selection (COUT)
          4. 9.2.2.2.4 Catch Diode Selection (D1)
          5. 9.2.2.2.5 Input Capacitor (CIN)
          6. 9.2.2.2.6 Boost Capacitor (CB)
        3. 9.2.2.3 Application Curves
      3. 9.2.3 Typical Application for All Output Voltage Versions
        1. 9.2.3.1 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
        1. 9.4.1.1 WSON Package Devices
      2. 9.4.2 Layout Examples
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 Custom Design with WEBENCH® Tools
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
9.2.2.2.2 Inductor Selection (L1)
  1. Calculate the inductor Volt • microsecond constant E • T (V • μs) from Equation 4.
    Equation 4. GUID-A5861866-02CA-42E1-A1F4-6F5E9E5B4357-low.png

    where

    • VSAT = internal switch saturation voltage = 0.25 V
    • VD = diode forward voltage drop = 0.5 V

    Calculate the inductor Volt • microsecond constant (E • T) with Equation 5.

    Equation 5. GUID-E3030F15-D653-4A2B-BCD3-2090C17714AE-low.png
  2. Use the E • T value from the previous formula and match it with the E • T number on the vertical axis of the inductor value selection guide shown in Figure 9-13.

    E • T = 21.6 (V • μs)

  3. On the horizontal axis, select the maximum load current.

    ILOAD(max) = 500 mA

  4. Identify the inductance region intersected by the E • T value and the maximum load current value. Each region is identified by an inductance value and an inductor code (LXX).

    From the inductor value selection guide shown in Figure 9-13, the inductance region intersected by the 21.6 (V • μs) horizontal line and the 500-mA vertical line is 100 μH, and the inductor code is L20.

  5. Select an appropriate inductor from the four manufacturer's part numbers listed in Table 9-7. For information on the different types of inductors, see the inductor selection in the fixed output voltage design procedure.

    From Table 9-7, locate line L20, and select an inductor part number from the list of manufacturers' part numbers.

Table 9-7 Inductor Manufacturers' Part Numbers
IND.
REF.
DESG.		INDUCTANCE
(μH)		CURRENT
(A)		SCHOTTRENCOPULSE ENGINEERINGCOILCRAFT
THROUGH HOLESURFACE MOUNTTHROUGH HOLESURFACE MOUNTTHROUGH HOLESURFACE MOUNTSURFACE MOUNT
L21500.216714392067144290RL-5470-4RL1500-150PE-53802PE-53802-SDO1608-154
L31000.266714393067144300RL-5470-5RL1500-100PE-53803PE-53803-SDO1608-104
L4680.326714394067144310RL-1284-68-43RL1500-68PE-53804PE-53804-SDO1608-683
L5470.376714831067148420RL-1284-47-43RL1500-47PE-53805PE-53805-SDO1608-473
L6330.446714832067148430RL-1284-33-43RL1500-33PE-53806PE-53806-SDO1608-333
L7220.526714833067148440RL-1284-22-43RL1500-22PE-53807PE-53807-SDO1608-223
L92200.326714396067144330RL-5470-3RL1500-220PE-53809PE-53809-SDO3308-224
L101500.396714397067144340RL-5470-4RL1500-150PE-53810PE-53810-SDO3308-154
L111000.486714398067144350RL-5470-5RL1500-100PE-53811PE-53811-SDO3308-104
L12680.586714399067144360RL-5470-6RL1500-68PE-53812PE-53812-SDO3308-683
L13470.76714400067144380RL-5470-7RL1500-47PE-53813PE-53813-SDO3308-473
L14330.836714834067148450RL-1284-33-43RL1500-33PE-53814PE-53814-SDO3308-333
L15220.996714835067148460RL-1284-22-43RL1500-22PE-53815PE-53815-SDO3308-223
L182200.556714404067144420RL-5471-2RL1500-220PE-53818PE-53818-SDO3316-224
L191500.666714405067144430RL-5471-3RL1500-150PE-53819PE-53819-SDO3316-154
L201000.826714406067144440RL-5471-4RL1500-100PE-53820PE-53820-SDO3316-104
L21680.996714407067144450RL-5471-5RL1500-68PE-53821PE-53821-SDO3316-683