NXP Semiconductors PCA9xxx I²C-bus LED Drivers offer unique blink modes and color mixing support. The PCA9551 LED driver blinks LEDs in I²C-bus and SMBus applications where it is necessary to limit bus traffic or free up the I²C-bus master's (MCU, MPU, DSP, chip set, etc.) timer. The internal oscillator has two programmable blink rates and requires only the initial set-up command to program them for each individual output. The NXP Semiconductors PCA9632 is an I²C-bus controlled 4-bit LED driver optimized for Red/Green/Blue/Amber (RGBA) color mixing applications, which offers individual brightness control mode, group dimming mode, and blink mode. The PCA9632 is in the new Fast-mode Plus (Fm+) family, which offers higher frequency (up to 1MHz) and more densely populated bus operation (up to 4000pF).