Worldsemi WS2913/SOP8

WS2913 is a three-channel LED driver control IC. The chip integrates an intelligent digital interface, data latch, signal reshaping amplifier driver circuit, a high-precision internal oscillator, and a 20V high-voltage programmable constant-current output driver. To reduce power supply ripple, the OUTR, G, and B channels feature a delayed turn-on function, which reduces circuit ripple during frame refresh.

The chip uses single-wire return-to-zero (RZ) communication. After power-on reset, the DIN pin receives data transmitted from the controller. The first 48 bits of incoming data are extracted by the first chip and stored in its internal data latch. The remaining data is reshaped and amplified by the internal signal reshaping circuit, then forwarded via the DO pin to the next cascaded chip. Each chip in the chain consumes 48 bits of the signal. The chip employs automatic reshaping and forwarding technology, so the number of cascadable chips is not limited by signal transmission degradation — only by signal transmission speed requirements.

Based on the received 48-bit data, the internal data latch generates PWM signals with different duty cycles on the OUTR, OUTG, and OUTB control outputs. When a RESET signal is received at the DIN pin, all chips simultaneously transfer the received data to their respective output stages. After this signal ends, the chip begins accepting new data. Once the initial 48 bits have been received, data is forwarded via the DO pin. Before a RESET code is received, the OUTR, OUTG, and OUTB pin outputs remain unchanged. Upon receiving a low-level RESET code of 280μs or longer, the chip outputs the 48-bit PWM data pulse widths just received to the OUTR, OUTG, and OUTB pins.

Available in SOP8 and FSOP8 packages.

• OUTR, G, B ports: 35V withstand voltage; DOUT, DIN ports: 24V withstand voltage.
• Built-in Zener diode; for sub-24V power supplies, only a series resistor to the VDD pin is required — no external Zener diode needed.
• Built-in resistors on DIN and DOUT ports with overvoltage protection; momentary short to 24V will not cause damage.
• Grayscale adjustment circuit (65536-level adjustable grayscale).
• Signal reshaping circuit: each IC reshapes the received waveform before output, preventing cumulative waveform distortion along the line.
• Built-in power-on reset and power-down reset circuits.
• PWM control input supports 65536-level adjustment.
• Serial cascade interface; data reception and decoding via a single signal line.
• Point-to-point transmission distance up to 4 meters with no additional circuitry required.
• At a refresh rate of 30 fps, cascade count is no less than 400 nodes.
• Data transmission speed up to 800Kbps.

• Full-color LED decorative lighting, such as LED strings, LED strips, LED modules, etc.
• Indoor/outdoor LED video or irregular displays.
• LED consumer electronics.
• Various LED lighting products.