SNVSA58C January   2015  – November 2017 LM26480-Q1

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Tables
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions: Bucks
    4. 7.4  Thermal Information
    5. 7.5  General Electrical Characteristics
    6. 7.6  Low Dropout Regulators, LDO1 and LDO2
    7. 7.7  Buck Converters SW1, SW2
    8. 7.8  I/O Electrical Characteristics
    9. 7.9  Power-On Reset Threshold/Function (POR)
    10. 7.10 Typical Characteristics — LDO
    11. 7.11 Typical Characteristics — Buck 2.8 V to 5.5 V
    12. 7.12 Typical Characteristics — Bucks 1 and 2
    13. 7.13 Typical Characteristics — Buck 3.6 V
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 DC-DC Converters
        1. 8.3.1.1 Linear Low Dropout Regulators (LDOs)
          1. 8.3.1.1.1 No-Load Stability
        2. 8.3.1.2 SW1, SW2: Synchronous Step-Down Magnetic DC-DC Converters
          1. 8.3.1.2.1  Functional Description
          2. 8.3.1.2.2  Circuit Operation Description
          3. 8.3.1.2.3  PWM Operation
          4. 8.3.1.2.4  Internal Synchronous Rectification
          5. 8.3.1.2.5  Current Limiting
          6. 8.3.1.2.6  PFM Operation
          7. 8.3.1.2.7  SW1, SW2 Control
          8. 8.3.1.2.8  Shutdown Mode
          9. 8.3.1.2.9  Soft Start
          10. 8.3.1.2.10 Low Dropout Operation
          11. 8.3.1.2.11 Flexible Power-On Reset (Power Good with Delay)
          12. 8.3.1.2.12 Undervoltage Lockout
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 External Component Selection
      2. 9.1.2 Feedback Resistors for LDOs
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 High VIN- High Load Operation
        2. 9.2.1.2 Junction Temperature
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Custom Design With WEBENCH® Tools
        2. 9.2.2.2 Output Inductors and Capacitors for SW1 AND SW2
          1. 9.2.2.2.1 Inductor Selection for SW1 and SW2
          2. 9.2.2.2.2 Suggested Inductors and Their Suppliers
        3. 9.2.2.3 Output Capacitor Selection for SW1 and SW2
        4. 9.2.2.4 Input Capacitor Selection for SW1 and SW2
        5. 9.2.2.5 LDO Capacitor Selection
          1. 9.2.2.5.1 Input Capacitor
          2. 9.2.2.5.2 Output Capacitor
          3. 9.2.2.5.3 Capacitor Characteristics
      3. 9.2.3 Application Curves
  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. 12.2 Documentation Support
      1. 12.2.1 Custom Design With WEBENCH® Tools
      2. 12.2.2 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Community 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

Features

  • Qualified for Automotive Applications
  • AEC Q100-Qualified With the Following Results
    • Device Temperature Grade 1: –40°C to +125°C Ambient Operating Temperature Range
  • Input Voltage: 2.8 V to 5.5 V
  • Compatible with Advanced Applications Processors and FPGAs
  • Two LDOs for Powering Internal Processor Functions and I/Os
  • Precision Internal Reference
  • Thermal Overload Protection
  • Current Overload Protection
  • External Power-On-Reset Function for Buck1 and Buck2
  • Undervoltage Lockout Detector to Monitor Input Supply Voltage
  • Step-Down DC-DC Converters (Buck)
    • 1.5-A Output Current
    • VOUT from:
    • Buck1 : 0.8 V to 2 V at 1.5 A
    • Buck2 : 1 V to 3.3 V at 1.5 A
    • Up to 96% efficiency
    • ±3% FB Voltage Accuracy
    • 2-MHz PWM Switching Frequency
    • PWM-to-PFM Automatic Mode Change Under Low Loads
    • Automatic Soft Start
  • Linear Regulators (LDO)
    • VOUT of 1 V to 3.5 V
    • ±3% FB Voltage Accuracy
    • 300-mA Output Current
    • 25-mV (Typical) Dropout

Applications

  • Core Digital Power
  • Applications Processors
  • Peripheral I/O Power

Description

The LM26480-Q1 is an automotive-qualified multi-functional power management unit (PMU), optimized for low-power digital applications. This device integrates two highly efficient 1.5-A step-down DC-DC converters and two 300-mA linear regulators. The DC-DC buck converters provide typical efficiencies of 96%, allowing for minimal power consumption. Features include soft start, undervoltage lockout, current overload protection, thermal overload protection, and an internal power-on-reset (POR) circuit, which monitors the output voltage levels on bucks 1 and 2.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM26480-Q1 WQFN (24) 4.00 mm × 4.00 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

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Simplified Schematic

LM26480-Q1 typapp_snvs543.gif

Revision History

Changes from B Revision (December 2016) to C Revision

  • Deleted the maximum lead temperature (soldering) from the Absolute Maximum Ratings tableGo
  • Changed the PBUCK1 and PBUCK2 equations in the Junction Temperature sectionGo
  • Changed the Electrostatic Discharge Caution statement Go

Changes from A Revision (June 2016) to B Revision

  • Changed data sheet title; add content to Description section Go

Changes from * Revision (January 2016) to A Revision

  • Added top navigator icon Go
  • Changed "θn" to "eN" as symbol for supply output noise in Low Dropout Regulators EC tableGo