Dim 18 LED Stripes (Staircase) with PWM

[fritzrichter]

Hi guys,
this is my first post, so I hope I am writing to the correct board.

So my plan is to develop a staircase LED dimmer, which lights up (smoothly) my stair steps. I started my project with a Aduino Uno, where I attached an additional board (12 Bit PWM Servo Driver) via IC2. Then I realized that with an ESP instead of Aduino, I get way more PWM channels with even higher resolution if I want. I read that I can use almost all GPIO to setup PWM.

Now, my staircase has 18 steps, unfortunately not 16. I now realized that I could use up to 32 GPIOs but actually only have 16 channels, so effectively I can only control 16 steps not 18.

I have this device ESP32 NodeMCU (https://www.az-delivery.de/en/products/ ... pmentboard).

What would you recommend to do? If there is now way of driving/controlling 18 channels directly via the ESP, then would you recommend to add a dedicated LED IC such as the LP5018 which offers 18 channels (12 bit)? Then the development will get a bit more complex as I can not use the plain ledcWrite commands etc.

[ESP_Minatel]

Hi,

Why don't you use an addressable LED strip instead of 18 separated?
You still can use an external PWM module and some PWM from the ESP to get the necessary channels in your project or you can use RMT for that.

[ESP_Sprite]

Another thing you can do is figure out what animations you want to use, and if they use more than 16 separate levels of grays at the same time. If not, you can (even dynamically) assign LEDC channels to multiple GPIOs to make these channels the same level of intensity, saving channels that way.