Features

➢ Backlight LED Driver
• Wide input range: 2.7V~5.5V
• High efficiency step-up LED driver with 6-Ch
current sinks, up to 40V 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
• 1.0MHz typical boost switching frequency
• 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: 2.7V~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 200mA at
VIN ≥ 2.9 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-28
• RoHS and Green Compliant
• -40°C to +85°C Temperature Range

Applications

• Tablet Backlight and Bias

Brief Description

KTZ8866 is the ideal power solution for LED backlighting
and LCD bias power of 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 2.7V to 5.5V, accommodating 1-cell lithium
ion batteries or 5V supply.
The LED driver’s six regulated current sinks can regulate
up to 30mA with its maximum boost output voltage up to
40V. 11-bit linear or exponential ILED resolution can be
obtained over I2C or PWM dimming. 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 KTZ8866 maximizes
conversion efficiency up to 85%.
Various protection features are built into KTZ8866,
including inductor current limit protection, output short
circuit protection, output over-voltage protection, LED fault
(open or short) protection and thermal shutdown
protection.
KTZ8866 is equipped with I2C interface for various controls
and status monitor.
KTZ8866 is available in a RoHS and Green compliant 28-
ball 1.73mm x 2.92mm x 0.62mm WLCSP package.