TFT LCD DC-DC Converter with Integrated
Charge Pumps and OP-AMP
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
Typical Application Circuit
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
3mm × 3mm TQFN-16 Package
RoHS Compliant and 100% Lead (Pb)-Free
DS2619 Ver0.1 Nov. 2011