RGB LED driver improves the user experience from both live effects and coding efforts

The Texas Instruments LP50xx device is an 18 or 24-channel constant-current-sink LED driver. The device increases the user experience in colour mixing and brightness control, from both live effects and coding efforts. The optimised performance for RGB LEDs makes it a possible choice for HMI applications. The device controls each LED output with a 12-bit PWM resolution at 29kHz switching frequency, which helps deliver a smooth dimming effect and eliminates audible noise. The independent colour mixing and brightness control registers make the software coding straightforward. When aiming for a fade-in, fade-out type breathing effect, the global R, G, B bank control decreases the microcontroller loading significantly. The device also performs a PWM phase-shifting function to help decrease the input power budget when LEDs turn on simultaneously. The device implements an automatic power-saving mode to produce ultralow quiescent current. When channels are all off for 30ms, the device total power consumption is down to 10µA, which makes the device a potential choice for battery-powered end-equipment.