MAXIM Integrated Products, represented in Australia by Arrow Electronics , has released the MAX8739, a step-up regulator with two high-current operational amplifiers for active-matrix, thin-film transistor (TFT) liquid crystal displays (LCD) in notebook and automotive applications.
The device has a 1.8V to 5.5V input supply voltage and includes a logic-controlled, high-voltage switch with adjustable delay. The step-up dc-dc converter provides the regulated supply voltage for the panel source-driver ICs and has been designed to work down to input voltages as low as 1.8V with high efficiency. The converter is a high-frequency (600kHz/1.2MHz) current-mode regulator with an integrated 14V n-channel MOSFET that allows use of ultra-small inductors and ceramic capacitors. It provides fast transient response to pulsed loads while achieving efficiency of over 85%.
The two operational amplifiers drive the LCD backplane (VCOM) and/or the gamma-correction-divider string. The MAX8739 converter has an output current of ±150mA, a slew rate of 7.5V/μs, a bandwidth of 12MHz and rail-to-rail inputs and outputs. The MAX8739 is available in a 5mm x 5mm, 20-pin thin QFN package with a 0.8mm maximum thickness for ultra-thin LCD panels.