Preliminary EUP2619 TFT LCD DC-DC Converter with Integrated Charge Pumps and OP-AMP DESCRIPTION FEATURES The EUP2619 generates power supply rails for thin-film transistor (TFT) liquid-crystal display (LCD) panels in tablet PCs and notebooks operated from 2.5V to 5.5V input supply. The device integrates a step-up converter, positive and negative charge pumps, and a high speed VCOM buffer. The external compensated step-up converter, providing the regulated supply voltage for the panel source driver ICs, features an internal power MOSFET and high frequency operation allowing to use small inductors and capacitors. The step up converter uses fixed-frequency peak current mode control architecture which provides fast load-transient response and easy compensation. A 2.8A peak current limit for the internal switch protects power supply fault condition. The regulated positive and negative charge pump regulators generate the positive and negative supply rails for the TFT LCD gate resistive voltage-divider ICs. The high speed VCOM buffer features 500mA short circuit current, 20MHz bandwidth, fast slew rate 45V/µs, and rail-to-rail inputs and outputs. The EUP2619 includes internal power-up sequencing, over/under voltage protections of the boost converter, and over temperature protection to ensure in safe operating. The EUP2619 are available in a 16-pin 3mm × 3mm TQFN packages. APPLICATIONS Typical Application Circuit Figure 1. DS2619 Ver0.1 Nov. 2011 2.5V to 5.5V Input Supply Range 1.2MHz Current-Mode Step-Up Converter - Built-In 20V/2.8A, 0.16Ω N-Channel MOSFET - High Efficiency Up to 90% - ±1% Accurate Output Voltage - Fast Transient Response to Pulse Load - Over-Current Protection - Output Under-Voltage Protection 600kHz Negative Charge Pump Driver for VGL 600kHz Positive Charge Pump Driver for VGH High Speed High Current 18V VCOM Buffer - ±500mA Output Short-Circuit Current - 45V/µs Slew Rate - 20MHz, -3dB Bandwidth - Rail-to-Rail Input and Output Power-On Sequence Control Thermal-Overload Protection 3mm × 3mm TQFN-16 Package RoHS Compliant and 100% Lead (Pb)-Free Halogen-Free 1 Tablet PCs Notebook Displays