EC9232-Multi-Channel TFT LCD Supply

EC9232-Multi-Channel TFT LCD Supply
General description
The EC9232 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 the frequency of 1.2MHz. The integrated N channel FET has a typical current limit of 3.0A and can support output voltages up to 20V. The gate-on and gate-off charge pumps provide regulated TFT-LCD gate-on and gate-off supplies. Both outputs can be adjusted by external resistive voltage-dividers. The GPM is a flicker compensation circuit to reduce the coupling effect of gate lines; the gate-shaping timing is controlled by the timing-controller to modulate the Gate-On voltage, VGHM. It also can delay the Gate-On voltage during power-on to achieve a correct power-on sequence for gate driver ICs. Both the power-on delay time and the falling time of the Gate-On voltage are programmable by external capacitor and resistor. The integrated operational amplifier is typically used for LCD VCOM driving; the output can sink or source up to 350mA short-circuit current. This operational amplifier features fast slew rate (40V/us), wide bandwidth (20MHz), and rail-to-rail outputs as well. A built-in voltage detector generates a reset signal when the input voltage drops below a specified level. The reset signal is active low, and the detecting level is decided by an external resistor divider. The EC9232 is available in a thin 24-pin 4×4 mm VQFN green package.

◆ 2.5V to 5.5V input supply

◆ Current-mode boost regulator

– 1.2MHz switching frequency

– Integrated 20V/3.0A 160mΩ FET

– Fast transient response to pulsed load

– High efficiency up to 90%

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

– Over current protection

– Over voltage protection

◆ VGH positive charge pump controller

◆ VGL negative charge pump controller

◆ Integrated high performance operational amplifier

– ±350mA output short-circuit current

– 40V/us fast slew rate

– 20MHz Bandwidth

– rail-to-rail output

◆ Low-voltage detection circuit

◆ GPM controller

– Adjustable falling time

– Adjustable delay

◆ Thermal shutdown

◆ Thin 4×4 mm 24-lead VQFN package

◆ TFT LCD for Notebooks

◆ TFT LCD for Monitors

◆ Car Navigation Display

◆ Portable equipment

Pin Configurations

Ordering info

Typical Applications circuit