MAX1884

MAX1778/MAX1880–MAX1885 Quad-Output TFT LCD DC/DC Converters with Buffer General Description The MAX1778/MAX1880–MAX1885 multiple-output DC-DC converters provide the regulated voltages required by active matrix thin-film transistor (TFT) liquid crystal displays (LCD) in a low-profile TSSOP package. One high-power step-up converter and two low-power charge pumps convert the 2.7V to 5.5V input voltage into three independent output voltages. A built-in linear regulator and VCOM buffer complete the power-supply requirements. The main step-up converter accurately generates an externally set output voltage up to 13V that can supply the display’s row/column drivers. The converter’s high switching frequency and current-mode PWM architecture provide fast transient response and allow the use of small lowprofile inductors and ceramic capacitors. The low-power BiCMOS control circuitry and internal 14V switch (0.35Ω N-channel MOSFET) enable efficiencies up to 91%. The dual low-power char...