The MAX17014A multiple-output power-supply controller generates all the supply rails for thin-film transistor (TFT) liquid-crystal display (LCD) panels in TVs and monitors operating from a regulated 12V input. It includes a step-down and a step-up regulator, a positive and a negative charge pump, two operational amplifiers, and a Dual Mode™ logic-controlled high-voltage switch control block. The MAX17014A can operate from 8V to 16.5V input voltages and is optimized for LCD TV panel and LCD monitor applications running directly from 12V supplies.
The step-up and step-down regulators feature internal power MOSFETs and high-frequency operation allowing the use of small inductors and capacitors, resulting in a compact solution. Both switching regulators use fixed-frequency current-mode control architectures, providing fast load-transient response and easy compensation. A current-limit function for internal switches and output-fault shutdown protect the step-up and step-down power supplies against fault conditions. The MAX17014A provides soft-start functions to limit inrush current during startup. The MAX17014A provides adjustable power-up timing.
The positive and negative charge-pump regulators provide TFT gate driver supply voltages. Both output voltages can be adjusted with external resistive voltage-dividers. The switch control block allows the manipulation of the positive TFT gate driver voltage.
The MAX17014A includes two high-current operational amplifiers designed to drive the LCD backplane (VCOM). The amplifier features high output current (±150mA), fast slew rate (100V/µs), wide bandwidth (20MHz), and rail-to-rail inputs and outputs. A series p-channel MOSFET is integrated to sequence power to AVDD after the MAX17014A has proceeded through normal startup, and provides True Shutdown™.
The MAX17014A is available in a small (7mm x 7mm), low-profile (0.8mm), 48-pin thin QFN package and operates over a -40°C to +85°C temperature range.
Applications
- LCD Monitor Panels
- LCD TV Panels
