The ADP8860 combines a programmable backlight LED charge pump driver with automatic phototransistor control. This combination allows for significant power savings because it changes the current intensity in office and dark ambient light conditions. By performing this function automatically, it eliminates the need for
a processor to monitor the phototransistor.
The light intensity thresholds are fully programmable via the I2C® interface. A second phototransistor input, with dedicated
comparators, improves the ambient light detection levels for various user operating conditions.
The ADP8860 allows as many as six LEDs to be independently driven up to 30 mA (maximum). A seventh LED can be driven to 60 mA (maximum). All LEDs are programmable for minimum/maximum current and fade in/out times via the I2C interface. These LEDs can also be combined into groups to reduce the
processor instructions during fade in/out.
Driving this entire configuration is a two-capacitor charge pump with gains of 1×, 1.5×, and 2×. This setup is capable of driving a
maximum IOUT of 240 mA from a supply of 2.5 V to 5.5 V. The device includes a variety of safety features including short-circuit, overvoltage, and overtemperature protection. These features allow easy implementation of a safe and robust design. Additionally, input inrush currents are limited via an integrated
soft start combined with controlled input to output isolation.
The ADP8860 is available in two package types, either a compact 2 mm × 2.4 mm × 0.6 mm WLCSP (wafer level chip scale package) or a small LFCSP (lead frame chip scale package).
