t KTZ8864 High Efficiency 4-CH LED Backlight Driver with Dual LCD Bias Power Features Brief Description Backlight LED Driver KTZ8864 is the ideal power solution for LED backlighting and LCD bias power of small and medium size panels. It Wide input range: 2.7V~5.5V integrates a step-up converter for LED backlighting, a step- High efficiency step-up LED driver with 4-Ch up converter with LDO and inverting charge pump for LCD current sinks, up to 32V boost voltage. bias power, resulting in a simpler and smaller solution with Up to 30mA/Ch in backlight mode fewer external components. High switching frequency 0.7% current matching at 20mA allows the use of a smaller inductor and capacitor. Its input 2.2% current accuracy at 20mA operating range is from 2.7V to 5.5V, accommodating 1- 2 I C/PWM dual dimming control scheme cell lithium ion batteries or 5V supply. 2 High resolution I C 11-bit linear or exponential dimming The LED drivers four regulated current sinks can regulate Wide range PWM dimming up to 30mA with its maximum boost output voltage up to 100Hz to 100kHz frequency 32V. 11-bit linear or exponential I resolution can be LED 2 0.2% to 100% duty cycle at 20kHz obtained over I C or PWM dimming. For additional Programmable current sink turn on/off ramp flexibility, PWM dimming offers wide range frequency and duty cycle to support Content Adaptive Brightness Control time/shape and transition ramp up/down time (CABC). Selectable boost switching frequency 1.0MHz or 500kHz with Auto-Frequency Mode supported The LCD bias power section includes a step-up converter, Programmable input PWM hysteresis to LDO and an inverting charge pump to generate dual minimize jitter at low PWM duty cycle outputs, OUTP and OUTN, whose voltages can be Programmable OVP and current limitation 2 programmed via an I C interface. By integrating LED open/short protection synchronous rectification MOSFETs for the step-up LCD Panel Bias converter and charge pump, the KTZ8864 maximizes Wide input range: 2.7V~5.5V conversion efficiency up to 85%. Programmable dual output Bias regulator using Various protection features are built into KTZ8864, a single inductor including inductor current limit protection, output short Programmable ramp time for OUTP and OUTN circuit protection, output over-voltage protection, LED fault Charge pump PFM mode at light load (open or short) protection and thermal shutdown LCD Bias efficiency: up to 85% protection. Wide dual output voltage range 4.0V to 6.3V 2 KTZ8864 is equipped with I C interface for various controls (50mV/step) and output current up to 120mA and status monitor. Active output discharge function Current limitation and short protection KTZ8864 is available in a RoHS compliant 24-ball 1.72mm Others x 2.45mm x 0.62mm WLCSP. System level input UVLO Thermal shutdown protection Low shutdown current <1A 2 Flexible I C interface Pb-free Packages: WLCSP-24 -40C to +85C Temperature Range Applications Smartphone/Tablet Backlight December 2019 - Revision 04d Page 1 Company Confidential t KTZ8864 Typical Application D L1 V OUT V IN 2.7V to 5.5V 4.7H C C IN OUT 10F 1.0F VIN LX BL VOUT L2 LX LCD 2.2H KTZ8864 S1 S2 S3 S4 HWEN PWM OUTP C POS SCL SOC 10F LCD SDA ENP OUTN C ENN NEG 10F CFLY1 C FLY REG 4.7F C REG CFLY2 10F PGND LCD AGND PGND CHP PGND BL December 2019 - Revision 04d Page 2 Company Confidential