Controlling 90 LEDs using one WS2811

arduinodriverledled striptransistors

I wanted to build a circuit where i would be able to control 90 LED's using one WS2811 and have a total of 60 WS2811.

In this circuit I hope to connect 30 LED's per channel, there is no need for me to control the individual LEDs thus there is no point in me going for the WS2812s which is commonly used.

I tried a few circuits that i saw online (sorry! dont have the links) and not of them worked, all i ended up was buring two of the IC's, and the circuit which did work I was unable to turn off the LED there was always a small amount of brightness.

Working voltage: 12V
No. of LED's per channel: 30

This is how the LEDs are wired
LED Wiring Diagram

I believe this is the circuit that i used
Test Circuit

I tried this circuit as well but the output is very low (brightness)
enter image description here


I modified the above circuit to 100ohm at R1 and 10k ohm at R2, the transistor T1 is BC547 and T2 is BC817. After modifying the resistors and transistors, I am able to get a much higher brightness however, if I am to connect the negative directly to ground the Strip (the one i am testing with) consumes 1A current but via this circuit it is consuming only 600mA. Do i need to change T1 for better results?



Best Answer

There is an older version of the WS2811, that's the WS2801. This chip also has a constant voltage option, so you can control a FET with it that PWM's all your LEDs. Have a look at page 10 of the datasheeet!

Edit: You would need some LEDs in series (say 3) with a resistor, you can then connect 10 of these sets of "3 leds and a resistor" in parallel, to feed everything from 12 volts.

To switch high currents with the WS2811, you can connect e.g. a 10k resistor from 12V to the OUT pins and drive a MOSFET (e.g. TSM2314) with the pwm signal coming from the OUT pins.