LP8867C-Q1, LP8869C-Q1 Low EMI Automotive LED Driver with 4-, 3- Channels

1 Features

• AEC-Q100 Qualified for automotive applications:
  • Device temperature grade 1:
    –40°C to +125°C, T_A
• 3-, 4-Channel 120-mA LED driver for automotive LCD display
  • High dimming ratio of 10 000:1 at 100 Hz
  • Current matching 1% (typical)
  • LED String current up to 120 mA per channel
  • Outputs can be combined externally for higher current per string
• Integrated boost and SEPIC converter for LED string power
  • Input voltage operating range 4.5 V to 40 V
  • Output voltage up to 45 V
  • Integrated 3.3-A Switch FET
  • Switching frequency 300 kHz to 2.2 MHz
  • Switching synchronization input
  • Spread spectrum for lower EMI
• Protection and fault detection
  • Fault output
  • Input voltage OVP, UVLO
  • Boost OVP
  • SW OVP
  • LED Open and short fault detection
  • Thermal shutdown

Simplified Schematic

2 Applications

• Backlight for:
  • Automotive infotainment
  • Automotive instrument clusters
  • Smart mirrors
  • Heads-up displays (HUD)

3 Description

The LP8867C-Q1, LP8869C-Q1 is an automotive highly-integrated, low-EMI, easy-to-use LED driver with DC-DC converter. The DC-DC converter supports both boost and SEPIC mode operation. The device has four or three high-precision current sinks that can be combined for higher current capability.

The DC-DC converter has adaptive output voltage control based on the LED forward voltages. This feature minimizes the power consumption by adjusting the voltage to the lowest sufficient level in all conditions. For EMI reduction DC-DC supports spread spectrum for switching frequency and an external synchronization with dedicated pin. A wide-range adjustable frequency allows the LP886xC-Q1 to avoid disturbance for sensitive frequency band.

The input voltage range for the LP886xC-Q1 is from 4.5 V to 40 V to support automotive stop, start and load dump condition. The LP886xC-Q1 integrates extensive fault detection features.

1. For all available packages, see the orderable addendum at the end of the data sheet.

System Efficiency