What is the different between WS2811 and WS2818?
WS2818 is an upgraded version of WS2811, it is a 3-channel LED drive control dedicated circuit, internal LED chip contains a smart digital interface data latch signal shaping amplifier drive circuit, high-precision internal oscillator, 12V high-voltage programmable constant current output driver and high-precision constant current control module; dual-channel signal transmission, single-chip damage does not affect the overall display effect (except for damage to two adjacent chips), supports DC12V low voltage input, 3 LEDs cuttable(one IC controls 3 LEDs); external IC.
The data protocol uses a single-wire return-to-zero code communication method. After the chip is powered on and reset, the DIN terminal receives the data and stores it in the data latch inside the chip, the remaining data is reshaped and amplified by the internal reshaping processing circuit and forwarded to the next pixel, the number of cascaded pixels is only limited by the signal transmission speed requirement, when using the BIN side as the control signal receiving port, the control data of the BIN port is 24 bits more than the control data of the DIN port, so as to ensure that the number of points controlled by the two methods is consistent.
Before the DIN terminal inputs, the RESET signal, the OUTR, OUTG, and OUTB control terminals generate different duty cycle control signals, keep the source output unchanged, and receive new data after receiving the RESET signal, and forward the data to the next pixel through the DO port, when receiving a low-level RESET code above 280us, the chip outputs 24bit PWM data pulse width to the OUTR, OUTG, and OUTB pins.