SNOSB22C October   2008  – October 2014 LM5574-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
    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 Shutdown And Standby
      2. 7.3.2 Current Limit
      3. 7.3.3 Soft-Start
      4. 7.3.4 Thermal Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 High Voltage Start-Up Regulator
      2. 7.4.2 Oscillator and Sync Capability
      3. 7.4.3 Error Amplifier and PWM Comparator
      4. 7.4.4 Ramp Generator
      5. 7.4.5 Maximum Duty Cycle and Input Drop-Out Voltage
      6. 7.4.6 Boost Pin
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Bias Power Dissipation Reduction
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  External Components
        2. 8.2.2.2  R3 (RT)
        3. 8.2.2.3  L1
        4. 8.2.2.4  C3 (CRAMP)
        5. 8.2.2.5  C9
        6. 8.2.2.6  D1
        7. 8.2.2.7  C1
        8. 8.2.2.8  C8
        9. 8.2.2.9  C7
        10. 8.2.2.10 C4
        11. 8.2.2.11 R5, R6
        12. 8.2.2.12 R1, R2, C2
        13. 8.2.2.13 R4, C5, C6
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Trademarks
    2. 11.2 Electrostatic Discharge Caution
    3. 11.3 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • LM5574-Q1 is an Automotive Grade Product That is AEC-Q100 Grade Qualified
  • −40°C to + 150°C Operating Junction Temperature
  • Integrated 75 V, 750 mΩ N-Channel MOSFET
  • Ultra-Wide Input Voltage Range From 6 V to 75 V
  • Adjustable Output Voltage as Low as 1.225 V
  • 1.65% Feedback Reference Accuracy
  • Operating Frequency Adjustable Between 50 kHz and 500 kHz With Single Resistor
  • Master or Slave Frequency Synchronization
  • Adjustable Soft-Start
  • Emulated Current Mode Control Architecture
  • Wide Bandwidth Error Amplifier
  • Built-In Protection
  • Package:
    • TSSOP-16

2 Applications

  • Automotive
  • Industrial

3 Description

The LM5574-Q1 is an easy to use SIMPLE SWITCHER® buck regulator which allows design engineers to design and optimize a robust power supply using a minimum set of components. Operating with an input voltage range of 6 - 75 V, the LM5574-Q1 delivers 0.5 A of continuous output current with an integrated 750 mΩ N-Channel MOSFET. The regulator utilizes an Emulated Current Mode architecture which provides inherent line regulation, tight load transient response, and ease of loop compensation without the usual limitation of low-duty cycles associated with current mode regulators. The operating frequency is adjustable from 50 kHz to 500 kHz to allow optimization of size and efficiency. To reduce EMI, a frequency synchronization pin allows multiple ICs from the LM(2)557x family to self-synchronize or to synchronize to an external clock. The LM5574-Q1 ensures robustness with cycle-by-cycle current limit, short-circuit protection, thermal shut-down, and remote shut-down. The device is available in a TSSOP-16 package. The LM5574-Q1 is supported by the full suite of WEBENCH® On-Line design tools.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LM5574-Q1 TSSOP (16) 5.00 mm x 4.40 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

Simplified Application Schematic

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