The DC-DC converter is a 1.2MHz current-mode stepup regulator with a built-in power MOSFET and provides the regulated supply voltage for the panel source driver ICs. The built-in power MOSFET allows output voltages to be as high as 18V from inputs of 2.5V to 6V. A built-in 7-bit digital soft-start function limits inrush currents during startup. The step-up regulator provides fast transient response to pulsed loads while producing efficiencies over 87%.
Three operational amplifiers, typically used as the gamma correction divider string, are configured as unity-gain buffers and feature high output short-circuit current (200mA), fast slew rate (45V/µs), and wide bandwidth (20MHz). Their rail-to-rail inputs and outputs maximize application flexibility.
Two linear regulators provide regulated gate-on and gate-off supplies for TFT panel. The two high-voltage switch control blocks modulate the shape of the gate-on supply with adjustable startup delay.
One operational amplifier is designed to drive the LCD backplane (VCOM). It features high short-circuit current of 200mA. The programmable VCOM calibrator adjusts the VCOM output-voltage level through serial interface by sinking a programmable current from the VCOM resistor-divider. The calibrator includes nonvolatile memory cells that store the desired VCOM voltage level.
The six independent high-voltage level-shifting scan drivers are designed to drive the TFT panel gate lines. The outputs swing from +35V (maximum) to -15V (minimum) and can swiftly drive capacitive loads.
The MAX17100 is available in a lead-free, 48-pin, thin QFN package with 0.4mm lead spacing. The package is a 6mm x 6mm square with a maximum thickness of 0.8mm for ultra-thin LCD panel design.
- Fast Transient Response to Pulsed Load
- High-Accuracy Output Voltage (1%)
- Built-In 20V, 3A, 0.16Ω n-Channel Power MOSFET
- Cycle-by-Cycle Current Limit
- High Efficiency (87%)
- 200mA Output Short-Circuit Current
- 45V/µs Slew Rate
- 20MHz, -3dB Bandwidth
- Rail-to-Rail Inputs and Outputs
- 7-Bit Adjustable Current-Sink Output
- Serial Interface
- Nonvolatile Setting Memory
LCD监视器
LCD TV