LP8545

www.DataSheet.co.kr LP8545 High-Efficiency LED Backlight Driver for Notebooks September 23, 2011 LP8545 High-Efficiency LED Backlight Driver for Notebooks General Description The LP8545 is a white LED driver with integrated boost converter. It has six adjustable current sinks which can be controlled by PWM input or with I2C-compatible serial interface. The boost converter has adaptive output voltage control based on the LED driver voltages. This feature minimizes the power consumption by adjusting the voltage to lowest sufficient level in all conditions. LED outputs have 8-bit current resolution and up to 13-bit PWM resolution with additional 1-3 bit dithering to achieve smooth and precise brightness control. Proprietary Phase Shift PWM control is used for LED outputs to reduce peak current from the boost converter, thus making the boost capacitors smaller. The Phase Shifting scheme also eliminates audible noise. Internal EEPROM is used for storing the configuration data. This makes it possible to have minimum external component count and make the solution very small. LP8545 has safety features which make it possible to detect LED outputs with open or short fault. As well low input voltage and boost over-current conditions are monitored and chip is turned off in case of these events. Thermal de-rating function prevents overheating of the device by reducing backlight brightness when set temperature has been reached. LP8545 is available in National's LLP 24-pin package. Fea...