SNVSA75D November   2015  – May 2017 LP8862-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  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  Internal LDO Electrical Characteristics
    7. 7.7  Protection Electrical Characteristics
    8. 7.8  Power Line FET Control Electrical Characteristics
    9. 7.9  Current Sinks Electrical Characteristics
    10. 7.10 PWM Brightness Control Electrical Characteristics
    11. 7.11 Boost or SEPIC Converter Characteristics
    12. 7.12 Logic Interface Characteristics
    13. 7.13 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 Integrated DC-DC Converter
      2. 8.3.2 Internal LDO
      3. 8.3.3 LED Current Sinks
        1. 8.3.3.1 Current Sink Configuration
        2. 8.3.3.2 Current Setting
        3. 8.3.3.3 Brightness Control
      4. 8.3.4 Power Line FET Control
      5. 8.3.5 Fault Detections
        1. 8.3.5.1 Adaptive DC-DC Voltage Control and Functionality of LED Fault Comparators
        2. 8.3.5.2 Overview of the Fault/Protection Schemes
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device States
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Typical Application for 2 LED Strings
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Inductor Selection
          2. 9.2.1.2.2 Output Capacitor Selection
          3. 9.2.1.2.3 Input Capacitor Selection
          4. 9.2.1.2.4 LDO Output Capacitor
          5. 9.2.1.2.5 Diode
          6. 9.2.1.2.6 Power Line Transistor
          7. 9.2.1.2.7 Input Current Sense Resistor
        3. 9.2.1.3 Application Curves
      2. 9.2.2 SEPIC Mode Application
        1. 9.2.2.1 Detailed Design Procedure
          1. 9.2.2.1.1 Inductor
          2. 9.2.2.1.2 Diode
          3. 9.2.2.1.3 Capacitor C1
        2. 9.2.2.2 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 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 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

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
  • Input Voltage Operating Range 4.5 V to 40 V
  • Two High-Precision Current Sinks
    • Current Matching 1% (Typical)
    • LED String Current up to 160 mA per Channel
    • Dimming Ratio of 10 000:1 at 100 Hz
  • Integrated Boost/SEPIC Converter for LED String Power
    • Output Voltage up to 45 V
    • Switching Frequency 300 kHz to 2.2 MHz
    • Switching Synchronization Input
    • Spread Spectrum for Lower EMI
  • Power-Line FET Control for Inrush Current Protection and Standby Energy Saving
  • Extensive Fault Detection Features
    • Fault Output
    • Input Voltage OVP, UVLO, and OCP
    • Open and Shorted LED Fault Detection
    • Thermal Shutdown
  • Minimum Number of External Components

2 Applications

  • Backlight for:
    • Automotive Infotainment
    • Automotive Instrument Clusters
    • Smart Mirrors
    • Heads-Up Displays (HUD)
    • Central Information Displays (CID)
    • Audio-Video Navigation (AVN)

    • System Efficiency

    LP8862-Q1 D001_SNVSA75.gif

3 Description

The LP8862-Q1 is an automotive high-efficiency, low-EMI, easy-to-use LED driver with integrated DC-DC converter. The DC-DC supports both boost and SEPIC modes of operation. The device has two high-precision current sinks that can provide high dimming ratio brightness control with a PWM input signal.

The boost/SEPIC converter has an adaptive output voltage control based on the LED current sink headroom voltages. This feature minimizes power consumption by adjusting the voltage to the lowest sufficient level in all conditions. DC-DC supports spread spectrum for switching frequency and an external synchronization with a dedicated pin. A wide-range adjustable frequency allows the LP8862-Q1 to avoid disturbance for AM radio band.

The input voltage range for the LP8862-Q1 is from 4.5 V to 40 V to support automotive stop/start and load dump conditions. The device supports PWM brightness dimming ratio of 10 000:1 for 100-Hz input PWM frequency. The LP8862-Q1 integrates extensive fault detection features. The device has an option to drive an external p-FET to disconnect the input supply from the system in the event of a fault. This feature also reduces inrush current and standby power consumption.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LP8862-Q1 HTSSOP (20) 6.50 mm × 4.40 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

LP8862-Q1 simp_schem_SNVSAM7_pg1.gif

4 Revision History

Changes from C Revision (April 2017) to D Revision

  • Enhanced descriptions for pins 3, 10, and 16 in Pin Functions tableGo
  • Deleted last line of Brightness Control subsectionGo

Changes from B Revision (July 2016) to C Revision

  • Deleted "IOUT = 100 mA" from tON/OFF row of Table 7.10Go
  • Changed "0.5" from MAX to TYP column in tON/OFF row of Table 7.10 Go
  • Added table note 1 for Tables 7.10 and 7.11Go
  • Deleted "Initial DC-DC voltage is about 88% of VMAX BOOST." from Integrated DC-DC Converter.Go
  • Changed Equation 1; add "K" eq definitions for Equation 1 and paragraph after Figure 7 Go
  • Added new paragraph before Internal LDO; changed Equation 3Go
  • Changed "less then" to "less than" - correction of typoGo

Changes from A Revision (November 2015) to B Revision

  • Changed "Output Current" to "LED String Current" Go
  • Changed "Dimming Ratio of 10 000:1 at 200 Hz" to "Dimming Ratio of 10 000:1 at 100 Hz" Go
  • Deleted some bullets from Features Go
  • Added some bullets to Features and minor revisions to wordingGo
  • Added several new Applications Go
  • Changed "The high switching frequency" to "A wide-range adjustable frequency" Go
  • Added table Go
  • Added Device Comparison table Go

Changes from * Revision (November 2015) to A Revision

  • Changed device from product preview to production data Go