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RT9921
Integrated Multi-Channel DC/DC Converter for TFT LCD Panels
General Description
The RT9921 includes a high-performance boost regulator, a low dropout linear regulator (LDO), a gate pulse modulator (GPM), a
voltage detector, a VCOM buffer (unitygain OPA), and a VGH charge pump controller for activematrix thin-film transistor (TFT) liquid-crystal displays (LCDs).
The boost converter provides the regulated supply
voltage for the panel source driver ICs.
The converter is a high switching frequency (640kHz or 1.
2MHz) current-mode regulator with an integrated 16V N-Channel 0.
2Ω
MOSFET that allows the use of ultra-small inductors and ceramic
capacitors.
It provides fast transient respons...