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 shortcircuit, 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).
### Features and Benefits
Charge pump with automatic gain selection of 1×, 1.5×, and 2× for maximum efficiency
Up to two built-in comparator inputs with programmable modes for ambient light sensing
Outdoor, office, and dark modes for maximum backlight power savings
7 independent and programmable LED drivers
6 drivers capable of 30 mA (maximum)
1 driver capable of 60 mA (maximum)
Programmable maximum current limit (128 levels)
Standby mode for <1μA current consumption
16 programmable fade in and fade out times 0.1 sec to 5.5 sec
Choose from linear, square, or cubic rates
Fading override
I2C-compatible interface for all programming
Dedicated reset pin and built-in power on reset (POR)
Short-circuit, overvoltage, and overtemperature protection
