WS2811N

WS2811N is a three-channel LED driver control IC in a DFN8 package, incorporating an intelligent digital interface with data latch signal shaping and amplification drive circuit, a high-precision internal oscillator, and a 20V high-voltage programmable constant-current output driver. To reduce power supply ripple, the 3 channels feature a delayed turn-on function. The chip uses single-wire return-to-zero (RZ) communication. After power-on reset, the DIN pin receives data; the first 24 bits of data are extracted by the first chip and stored in its internal data latch, while the remaining data is reshaped, amplified, and forwarded to the next chip via the DO pin. The internal data latch generates control signals with different duty cycles on the OUTR, OUTG, and OUTB outputs based on the 24-bit data; upon receiving a RESET signal, all chips simultaneously transfer data to their respective segments. After receiving 24 bits of data, the chip forwards it through the DO pin. Before receiving a RESET code, the OUTR, OUTG, and OUTB pin outputs remain unchanged. Upon receiving a RESET code with a low level of 280μs or longer, the 24-bit PWM data pulse width is output to the OUTR, OUTG, and OUTB pins.

Applications

• LED full-color illuminated letter light strings
• LED full-color modules
• LED full-color flexible and rigid light strips
• LED guardrail tubes
• LED point light sources

Key features

• R, G, B output ports rated at 20V; DIN port rated at 9.5V.
• Built-in voltage regulator; for power supplies below 24V, simply connect a series resistor to the IC VDD pin — no external voltage regulator required.
• Grayscale adjustment circuit (256-level adjustable grayscale).
• Built-in signal reshaping circuit; each IC reshapes the received signal before forwarding, preventing cumulative waveform distortion along the line.
• Built-in power-on reset and power-down reset circuits.
• PWM control supports 256-level adjustment with a scan frequency of 2kHz.
• Serial cascade interface — data reception and decoding via a single signal line.
• Point-to-point transmission distance up to 5 meters with no additional circuitry required.
• Cascade count no less than 1024 nodes at a refresh rate of 30 frames/second.
• Data transmission speed up to 800Kbps.