EC9223-Multi-Channel TFT LCD Supply

General description

TheEC9223 is an integrated power supply solution optimized for small to medium size thin- film transistor (TFT) liquid crystal displays (LCD’s). The boost converter operates  at a fixed frequency of 1.2MHz. The integrated N-channel FET has a current limit of 1.8A. The positive and negative charge pumps provide regulated  TFT  LCD  gate-on  and gate-off supplies. Both outputs can be adjusted by external resistive voltage dividers.

The integrated operational amplifier is typically used for LCD VCOM driving; the output can sink or source up to 150mA short-circuit current. A built-in voltage detector generates a reset signal when the input voltage drops below 2.6V. The reset signal is active low and has a 123ms blanking time during power-on. The EC9223 is available in a thin 16-pin 3×3 mm WQFN green package.

Features

◆ 2.5V to 5.5V input supply

◆ Active-high Enable Control

◆ Current-mode boost regulator

– 1.2MHz switching frequency

– Integrated 20V/1.8A 700mΩ FET

– Fast transient response to pulsed load

– High efficiency up to 90%

– Adjustable high-accuracy output voltage(±1%)

◆ VGH positive charge pump

◆ VGL negative charge pump

◆ Integrated unity-gain VCOM buffer

– ±150mA output current limit

– 12V/us slew rate

– 12MHz Bandwidth

◆  Low-voltage detection circuit

◆ Soft-start and timed delay fault latch for all outputs

◆ Thermal shutdown

◆ Thin 3×3 mm 16-lead WQFN package

Applications

◆ TFT LCD for Notebooks

◆ Tablet Personal Computer Display

◆ Car Navigation Display

◆ Portable equipment

Pin Configurations

Ordering info

Typical Applications circuit

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