18-channel I2C constant-current RGB LED driver

In smart homes and other applications that utilize human-machine-interaction,high-performance RGB LED drivers are required. LED animation effects such as flashing, breathing,and chasing greatly improve user experience, and minimal system noise is essential.

The LP50xx device is an 18- or 24-channel constant current sink LED driver. The LP50xxdevice includes integrated color mixing and brightness control, and pre-configuration simplifiesthe software coding process. Integrated 12-bit, 29 kHz PWM generators for each channel enablesmooth, vivid color for LEDs, and eliminate audible noise.

The LP50xx device controls each LED output with a 12-bit PWM resolution at 29-kHzswitching frequency, which helps achieve a smooth dimming effect and eliminates audible noise. Theindependent color mixing and intensity control registers make the software coding straightforward.When targeting a fade-in, fade-out type breathing effect, the global R, G, B bank control reducesthe microcontroller loading significantly. The LP50xx device also implements a PWM phase-shiftingfunction to help reduce the input power budget when LEDs turn on simultaneously.

The LP50xx device implements an automatic power-saving mode to achieve ultralow quiescentcurrent. When channels are all off for 30 ms, the device total power consumption is down to 10 µA,which makes the LP50xx device a potential choice for battery-powered end equipment.