The WS2821A is a type of integrated circuit (IC) produced by Worldsemi, a leading provider of driver ICs for LED lighting applications. It is a three-channel switchable, full-color LED driver IC for RGB (red, green, blue) lamp applications. The WS2821A integrates a power switch, 3-channel pulse width modulation (PWM) generator, low-voltage shift register and output driver circuitry into a single IC. It is designed to drive up to 3 strings of full-color LED arranged in a common cathode or common anode configuration. The WS2821A can drive a maximum of six LEDs with each string up to four LEDs. It can operate in constant-current and constant-voltage mode depending on the requirement of the application. Furthermore, the IC supports both static and dynamic color control allowing the user to adjust the LED brightness and color directly from the input signal.