Austria-based designer of high-performance analog integrated circuits, austriamicrosystems has launched a 40 mA, 12-bit PWM, 16-channel LED driver, the AS1121.
With a LED supply voltage of 30 V, the AS1121 can be used with 24 V or higher supplies since it does not require as many external support components as alternative devices.
The LED driver meets the requirements of advanced LED video walls, which require good picture quality. It can also be utilized for generating ambient light patterns or in TVs and monitors, which require LED backlighting. A 6-bit dot correction feature in the AS1121 allows for full-color LED displays in public transport, stadiums, street signs, outdoor and indoor displays and LED video walls.
A 4096-step greyscale PMW brightness control, which runs at 10 MHz, can individually adjust each of the 16 channels of the AS1121. A maximum current value can be set on all channels by an external resistor. A 64-step constant current sink controls the dot correction feature, which adjusts the brightness variation on each channel of the LEDs. A serial interface with SPI-compatibility allows access to the dot correction circuitry and the grayscale control. Additionally, disconnected or broken LEDs are indicated by an open-LED detector.
Other features of the AS1121 include a power-down pin and an over-temperature signal. It is enclosed in a 32-pin 5x5 mm TQFN package. The LED driver is suitable for a 3.3 V power supply at an ambient temperature range between -40° and +85°C.