SNVSAD9 April   2016 LM5175-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Simplified Schematic
  5. 5 Revision History
  6. 6 Pin Configuration and Functions
  7. 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
    6. 7.6 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Fixed Frequency Valley/Peak Current Mode Control with Slope Compensation
      2. 8.3.2  VCC Regulator and Optional BIAS Input
      3. 8.3.3  Enable/UVLO
      4. 8.3.4  Soft-Start
      5. 8.3.5  Overcurrent Protection
      6. 8.3.6  Average Input/Output Current Limiting
      7. 8.3.7  CCM/DCM Operation
      8. 8.3.8  Frequency and Synchronization (RT/SYNC)
      9. 8.3.9  Frequency Dithering
      10. 8.3.10 Output Overvoltage Protection (OVP)
      11. 8.3.11 Power Good (PGOOD)
      12. 8.3.12 Gm Error Amplifier
      13. 8.3.13 Integrated Gate Drivers
      14. 8.3.14 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown, Standby, and Operating Modes
      2. 8.4.2 MODE Pin Configuration
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1  Frequency
        2. 9.2.2.2  VOUT
        3. 9.2.2.3  Inductor Selection
        4. 9.2.2.4  Output Capacitor
        5. 9.2.2.5  Input Capacitor
        6. 9.2.2.6  Sense Resistor (RSENSE)
        7. 9.2.2.7  Slope Compensation
        8. 9.2.2.8  UVLO
        9. 9.2.2.9  Soft-Start Capacitor
        10. 9.2.2.10 Dither Capacitor
        11. 9.2.2.11 MOSFETs QH1 and QL1
        12. 9.2.2.12 MOSFETs QH2 and QL2
        13. 9.2.2.13 Frequency Compensation
      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 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Package Option Addendum
      1. 13.1.1 Packaging Information

Package Options

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

1 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
    • Device HBM ESD Classification Level 2
    • Device CDM ESD Classification Level C4B
  • Single Inductor Buck-Boost Controller for Step-Up/Step-Down DC/DC Conversion
  • Wide VIN Range: 3.5 V to 42 V, 60 V Maximum
  • Flexible VOUT Range: 0.8 V to 55 V
  • VOUT Short Protection
  • High Efficiency Buck-Boost Transition
  • Adjustable Switching Frequency
  • Optional Frequency Sync and Dithering
  • Integrated 2-A MOSFET Gate Drivers
  • Cycle-by-Cycle Current Limit and Optional Hiccup
  • Optional Input or Output Average Current Limiting
  • Programmable Input UVLO and Soft-Start
  • Power Good and Output Overvoltage Protection
  • Selectable CCM or DCM with Pulse Skipping
  • HTSSOP-28 Package

2 Applications

  • Automotive Start-Stop Systems
  • Backup Battery and Supercapacitor Charging
  • Industrial PC Power Supplies
  • USB Power Delivery
  • LED Lighting

3 Description

The LM5175-Q1 is a synchronous four-switch buck-boost DC/DC controller capable of regulating the output voltage at, above, or below the input voltage. The LM5175-Q1 operates over a wide input voltage range of 3.5 V to 42 V (60 V maximum) to support a variety of applications.

The LM5175-Q1 employs current-mode control both in buck and boost modes of operation for superior load and line regulation. The switching frequency is programmed by an external resistor and can be synchronized to an external clock signal.

The device also features a programmable soft-start function and offers protection features including cycle-by-cycle current limiting, input undervoltage lockout (UVLO), output overvoltage protection (OVP), and thermal shutdown. In addition, the LM5175-Q1 features selectable Continuous Conduction Mode (CCM) or Discontinuous Conduction Mode (DCM) operation, optional average input or output current limiting, optional spread spectrum to reduce peak EMI, and optional hiccup mode protection in sustained overload conditions.

Device Information(1)

ORDER NUMBER PACKAGE BODY SIZE
LM5175-Q1 HTSSOP-28 9.7 mm x 4.4 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

4 Simplified Schematic

LM5175-Q1 schematic_frontpage.gif