Charge Pump Driven 9-Channel LED Driver with
Automated LED Lighting Effects
Preliminary Technical Data
ADP8866
FEATURES
APPLICATIONS
Charge pump with automatic gain selection of 1×, 1.5×, and
2× for maximum efficiency.
92% peak efficiency
9 independent and programmable LED drivers
Each driver capable of 25 mA (full scale)
Each driver has 7 bits (128 levels) of non-linear current
settings
Mobile display backlighting
Mobile phone keypad backlighting
LED indication and status lights
Automated LED blinking
TYPICAL OPERATING CIRCUIT
Standby mode for <1 µA current consumption
16 programmable fade in and fade out times (0.0 sec to 1.75
sec) with choice of square or cubic rates
Automated and customizable LED blinking for all 9 channels.
Unique heartbeat mode for customizable double pulse
lighting effects
PWM input for implementing content adjustable brightness
control (CABC)
I2C compatible interface for all programming
Dedicated reset pin and built-in power on reset (POR)
Short circuit, overvoltage, and overtemperature protection
Internal soft start to limit inrush currents
Input to output isolation during faults or shutdown
Operates down to VIN = 2.5 V, with undervoltage lockout
(UVLO) at 2.0 V
Figure 1.
Small lead frame chip scale package (LFCSP)
GENERAL DESCRIPTION
Driving all of this is a two capacitor charge pump with gains of
1×, 1.5×, and 2×. This setup is capable of driving a maximum
The ADP8866 combines a programmable backlight LED charge
pump driver with automatic blinking functions. Nine LED
drivers can be independently programmed at currents up to
25 mA. The current level, fade time, and blinking rate can be
programmed once and executed autonomously on a loop.
Separate fade in and out times can be set for the backlight LEDs.
I
OUT of 240 mA from a supply of 2.5 V to 5.5 V. A full suite of
safety features including short-circuit, overvoltage, and over-
temperature protection 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.
Rev. PrA
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