High Efficiency 3-CH LED Backlight Driver with Dual LCD Bias Power

Description

KTZ8863A is the ideal power solution for LED backlighting and LCD bias power of small and medium size panels. It integrates a step-up converter for LED backlighting, a step-up converter with LDO and inverting charge pump for LCD bias power, resulting in a simpler and smaller solution with fewer external components. High switching frequency allows the use of a smaller inductor and capacitor. Its input operating range is from 2.9V to 5.5V, accommodating 1-cell lithium ion batteries or 5V supply.

The LED driver’s three regulated current sinks can regulate up to 30mA with its maximum boost output voltage up to 32V. 11-bit linear or exponential ILED resolution can be obtained over I2C or PWM diming. For additional flexibility, PWM dimming offers wide range frequency and duty cycle to support Content Adaptive Brightness Control (CABC).

The LCD bias power section includes a step-up converter, LDO and an inverting Charge Pump to generate dual outputs OUTP and OUTN, whose voltages can be programmed via an I2C interface. By integrating synchronous rectification MOSFETs for the step-up converter and charge pump, the KTZ8863A maximizes conversion efficiency up to 90%.

Various protection features are built into KTZ8863A, including inductor current limit protection, output short circuit protection, output over-voltage protection, LED fault (open or short) protection and thermal shutdown protection.
KTZ8863A is equipped with I2C interface for various controls and status monitor.

KTZ8863A is available in a RoHS and Green compliant 24-ball 1.72mm x 2.45mm WLCSP.

Features

Backlight LED Driver

  • Wide input range: 2.9V~5.5V
  • High efficiency step-up LED driver with 3-Ch current sinks, up to 32V boost voltage.
    • Up to 30mA/Ch in backlight mode
    • ±0.7% current matching at 20mA
    • ±2.2% current accuracy at 20mA
  • I2C/PWM dual dimming control scheme
    • High resolution I2C 11-bit linear or exponential dimming
    • Wide range PWM dimming
      • 100Hz to 100kHz frequency
      • 0.2% to 100% duty cycle at 20kHz
  • Programmable current sink turn on/off ramp time/shape and transition ramp up/down time
  • Selectable boost switching frequency 1.0MHz or 500kHz with Auto-Frequency Mode supported
  • Programmable input PWM hysteresis to minimize jitter at low PWM duty cycle
  • Programmable OVP and current limitation
  • LED open/short protection

LCD Panel Bias

  • Wide input range: 2.9V~5.5V
  • Programmable dual output Bias regulator using a single inductor
  • Programmable ramp time for OUTP and OUTN
  • Charge pump PFM mode at light load
  • LCD Bias efficiency: up to 85%
  • Wide dual output voltage range ±4.0V to ±6.3V (50mV/step) and output current up to 150mA
  • IREG_OUT up to 300mA at VREG_OUT = 6.0 V, VIN ≥ 3.0 V
  • Active output discharge function
  • Current limitation and short protection

Others

  • System level input UVLO
  • Thermal shutdown protection
  • Low shutdown current <1μA
  • Flexible I2C interface
  • Pb-free Packages: WLCSP-24
  • RoHS and Green Compliant
  • -40°C to +85°C Temperature Range

Applications

  • Smartphone/Tablet Backlight

Packaging Information

Package Dimensions Package Code
WLCSP46-24 1.72mm x 2.45mm x 0.62mm JAA

Technical Documentation

Description Documents Type
DatasheetKTZ8863A-04bPDF

Purchase

Purchase Options
Buy from Digi-Key
Buy from Mouser