WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC Feature Applications l l l l l l l l l l l Output port compression 12V. Built in stabilivolt, Only add a resistance to IC VDD feet when under 24V power supply. Gray level 256 can be adjusted and scan freque ncy not less than 400Hz/s. Built in signal reshaping circuit,after wave reshaping to the next driver, ensure wave-form distortion not accumulate. Built-in electric reset circuit and power lost reset circuit. Cascading port transmission signal by single line. Any two point the distance more than 10m transmission signal without any increasecircuit. When the refresh rate is 30fps, low speedmodelc ascade number are not less than 512 points, high speed mode not less than1024 points. Send data at speeds of up to 400 Kbps and 800 Kbps two patterns. LED decorative lighting. Indoor/outdoor LED video or irregular screen. General description The WS2811 is 3 output channels special for LED driver circuit. It internal include intelligent digital port data latch and signal reshaping amplification drive circuit.Also include a precision internal oscillator and a 12V voltage programmable constant current output drive. In the purpose of reduce power supply ripple, the 3 output channels designed to delay turn-on function. IC use single NZR communication mode.After the chip power-on reset, the DIN port receivedata from con troller, the first IC collect initial 24bit data then sent to the internal data latch, theother data which reshaping by the internal signal reshaping amplification circuit sent to the next cascade IC through the DO port. After transmission for each chip,the signal to reduce 24bit. IC adopt auto reshaping transmit technology, making the chip cascade number is not limited the signal transmission, only depend on the speed of signal transmission. The data latch of IC depend on the received 24bit data produce different duty ratio signal at OUTR, OUTG, OUTB port. All chip synchronous send the received data to each segment when the DIN port input a reset signal. It will receive new data again After the reset signal finished. Before a new reset signal received, the control signal of OUTR ,OUTG, OUTB port unchanged. IC sent PWM data that received justly to OUTR, OUTG, OUTB port, after receive a low voltage reset signal the time retain over 50us. We offer two package SOP8 and DIP8. http://www.world-semi.com WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC PIN configuration PIN function NO. Symbol Function description 1 OUTR Output of Red PWM control 2 OUTG Output of Green PWM control 3 OUTB Output of Blue PWM control 4 GND Ground 5 DOUT Data signal cascade output 6 DIN 7 SET 8 VDD Data signal input Set work mode of IC as low speed model(connect VDD) or high speed model(vacant) Power supply voltage Absolute Maximum Ratings Prameter Symbol Ratings Unit Power supply voltage VDD +6.0~+7.0 V Output voltage VOUT 12 V Input voltage VI -0.5～VDD+0.5 V Operation junction temperature Topt -25～+85 ℃ Storage temperature range Tstg -55~+150 ℃ Note: If the voltage on the pins exceeds the maximum ratings may cause permanent damage to the device. http://www.world-semi.com WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC Electrical Characteristics（TA=-20～+70℃，VDD=4.5～5.5V,VSS=0V,unless otherwise specified） Prameter Smybol conditions Min Tpy Max Unit Low voltage output current IOL ROUT —— 18.5 —— mA Idout Vo=0.4V，DOUT 10 —— —— mA Input current II VI=VDD/VSS —— —— ±1 µA VIH DIN，SET 0.7VDD —— —— V VIL DIN，SET —— —— 0.3 VDD V VH DIN，SET —— 0.35 —— V Input voltage level Hysteresis voltage Switching characteristics（TA=-20～+70℃，VDD=4.5～5.5V,VSS=0V,unless otherwise specified） Prameter Symbol Condition Min Tpy Max Unit Operation frequency Fosc1 —— —— 400 —— KHz Fosc2 —— —— 800 —— KHz Transmission delay time tPLZ CL=15pF,DIN→ DOUT,RL=10KΩ —— —— 300 ns Fall time tTHZ CL=300pF,OUTR/ OUTG/OUTB —— —— 120 µs Data transmission rate FMAX Duty ratio50% 400 —— —— Kbps Input capcity CI —— —— 15 pF —— Low Speed mode time T0H 0 code,high voltage time 0.5 µs ±150ns T1H 1 code,high voltage time 1.2 µs ±150ns T0L 0 code,low voltage time 2.0 µs ±150ns T1L 1 code,low voltage time 1.3 µs ±150ns RES low voltage time Above 50µs Note: It is one half of the time when high speed mode(reset time unchanged) http://www.world-semi.com WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC D1 Sequence chart: 0 co d e T0 L T0H D2 DIN DO DIN DO IC 1 IC 2 D3 D4 DIN DO IC 3 T1L 1 cod e T1 H Treset R ET co d e Cascade method: reset code >=50us Data refresh cycle 1 D1 first 2 4 b it Data refresh cycle 2 seco n d 2 4 b it th ird 2 4 b it seco n d 2 4 b it D2 reset code first 2 4 b it th ird 2 4 b it seco n d 2 4 b it th ird 2 4 b it seco n d 2 4 b it th ird 2 4 b it th ird 2 4 b it D3 th ird 2 4 b it D4 Data transmission method: Note: The data of D1 is send by MCU,and D2, D3, D4 through IC internal reshaping amplification to transmit. Composition of 24bit data: R7 R6 R5 R4 R3 R2 R1 R0 G7 G6 G5 G4 G3 G2 G1 G0 Note: Follow the order of RGB to sent data and the high bit sent at first. http://www.world-semi.com B7 B6 B5 B4 B3 B2 B1 B0 WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC Typical application circuit: 1.power supply is 5V with 1 LED and constant current (18.5mA) driving 5V 5V G B R B 100R depend on controller G R 100R 104 104 LED control ler VCC 33R 33R VDD OUTB OUTG OUTR DAT DI N GND GND 33R VDD OUTB OUTG OUTR DO DI N GND GND WS2811 DO 33R WS2811 GND Fig 1 This driving mode use constant current output, the advantage of is the LED can retain luminance and colour temperature when the power supply lessen. We require, in order to prevent power spikes phenomenon and power reverse polarity, series a not more than 100ohm resistor at the po-wer supply pin(VDD). The capacitance 104 as bypass capacitor. To prevent the reflection and hot-swap protection, we suggest to connect a 33 ohm resistor at the data input or output port for impedance. 2.power supply is 12V with 3 LED and constant current(18.5mA) driving 12V 12V B G R B G R B G R B G R B G R B G R R1 R1 depend on controller RR RR 104 104 LED controller VCC 33R VDD OUTB OUTG OUTR DAT DIN GND GND 33R 33R VDD OUTB OUTG OUTR DO DIN GND GND WS2811 DO 33R WS2811 GND Fig 2 The same as the front mode, it is also use constant current output. In this circuit, R1 is used as the IC internal LDO divider resistance and the value is 2.7K. The capacitance 104 as bypass capacitor. To prevent the reflection and hot-swap protection, we suggest to connect a 33ohm resistor at the data input or output port for impedance. At the OUTR port we should add a divider resistance RR. The value of RR can be derived by the following equation: RR = 12 - 3V LEDR KΩ 18 .5 VLEDR is the red LED forward conduction voltage drop. http://www.world-semi.com WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC Package imformation: DIP-8 Package: Symbo l Dimensions In Millmeters Min Nom Max Min Nom Max A — — 4.31 — — 0.170 A1 0.38 — — 0.015 — — A2 3.15 3.40 3.65 0.124 0.134 0.144 B 0.38 0.46 0.51 0.015 0.018 0.020 B1 1.27 1.52 1.77 0.050 0.060 0.070 C 0.20 0.25 0.30 0.008 0.010 0.012 D 8.95 9.20 9.45 0.352 0.362 0.372 E 6.15 6.45 6.65 0.242 0.252 0.262 E1 — 7.62 — — 0.300 — e — 2.54 — — 0.1 — L 3.00 3.30 3.60 0.118 0.130 0.142 θ 0º — 15º 0º — 15º http://www.world-semi.com Dimensions In Inches WS2811 Signal line 256 Gray level 3 channal Constant current LED drive IC SOP-8 Package: Symbol Dimensions In Millmeters Dimensions In Inches Min Max Min Max A 1.350 1.750 0.053 0.069 A1 0.100 0.250 0.004 0.010 A2 1.350 1.550 0.053 0.061 b 0.330 0.510 0.013 0.020 c 0.170 0.250 0.006 0.010 D 4.700 5.100 0.185 0.200 E 3.800 4.000 0.150 0.157 E1 5.800 6.200 0.228 0.244 e 1.270 0.050 L 0.400 1.270 0.016 0.050 θ 0º 8º 0º 8º http://www.world-semi.com