The ANX6621 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 selectable switching frequency of 640k/1.2MHz. The integrated N-channel FET has a typical current limit of 2.0A and can support output voltages up to 16V.
A positive charge pump with an integrated driver can produce up to 40V of positive gate drive.
The integrated Vcom unity-gain buffer with an adjustable output voltage can sink or source up to 150mA short-circuit current and up to 75mA continuous current.
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.
To minimize the inrush current, the soft-start period can be adjusted by an external capacitor.
A built-in voltage detector generates a reset signal when the input voltage drops below a specified level. The detecting level is decided by an external resistor divider and the delay time is programmable by an external capacitor.
The ANX6621 is available in a thin 24-pin 4x4 mm VQFN green packa.
l 2.5V to 5.5V input supply
l 640k/1.2MHz switching frequency
l Current-mode boost regulator
- Integrated 16V/2.0A 200mΩ FET
- Fast transient response to pulsed load
- High efficiency up to 90%
- Adjustable high-accuracy output voltage (±1%)
- Adjustable soft-start
- Over current protection
- Output under voltage protection
l VGH positive charge pump controller
l Low-dropout voltage linear regulator
- Adjustable output voltage (±1.5%)
- 350mA maximum output current
l Unit gain Vcom buffer amplifier
- 12MHz bandwidth
- 12V/µs slew rate
- 150mA output current limit
l Low-voltage detection circuit
- Programmable detecting voltage and delay time
l GPM controller with adjustable falling time
- Flicker compensator
- Power-on sequence control
l Thermal shutdown
l Thin 4x4 mm 24-lead VQFN package
QFN-24 PIN CONFIGURATION