SNVSA72 February   2015 LP8728D-Q1

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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 System Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Buck Information
        1. 7.3.1.1 Features
      2. 7.3.2 Thermal Shutdown (TSD)
      3. 7.3.3 Undervoltage Lockout (UVLO)
      4. 7.3.4 Overvoltage Protection (OVP)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Active Mode
  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 Inductor
        2. 8.2.2.2 Input and Output Capacitors
      3. 8.2.3 Application Performance Plots
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Related Documentation
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

1 Features

  • LP8728D-Q1 is an Automotive Grade Product that is AECQ-100 Grade 1 Qualified
  • Four High Efficiency Step-Down DC-DC Converters:
    • 93% Peak Efficiency (VIN = 5 V, VOUT = 3.3 V)
    • Max Output Current 1 A
    • Forced PWM Operation
    • Soft-Start Control
    • VOUT1 = 3.3 V
    • VOUT2 = 1.25 V
    • VOUT3 = 1.8 V or 2.65 V (pin selectable)
    • VOUT4 = 1.8 V
  • Separate Enable Inputs for each Converter Control
  • Separate Power Good Outputs for each Converter
  • Output Overcurrent and Input Overvoltage Protection
  • Overtemperature Protection
  • Undervoltage Lockout (UVLO)

2 Applications

  • FPGA, DSP Core Power
  • Processor Power for Mobile Devices
  • Peripheral I/O Power
  • Automotive Safety Cameras
  • Automotive Infotainment

3 Description

The LP8728D-Q1 is a quad-output Power Management Unit (PMU), optimized for low-power FPGAs, microprocessors, and DSPs for automotive applications. This device integrates four highly efficient step-down DC-DC converters into one package. Each converter has high current capability and separate controls which allows flexibility to use the device in multiple applications. All the converters operate above the AM band with a fixed 3.2-MHz switching frequency. The high-side switch turn-on time of each converter is phase shifted to minimize input current spikes.

Protection features include output short-circuit protection, switch current limits, input overvoltage protection, input undervoltage lockout, and thermal shutdown functions. During start-up, the device controls the output slew rate to minimize output voltage overshoot and the input inrush current.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LP8728D-Q1 WQFN (28) 5.00 mm x 5.00 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

Simplified Schematic

LP8728_Typ_app_141219.gif

Efficiency

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