I2S Clockless LED Strip

The i2s_clockless_led_strip light platform drives a clockless addressable LED strip with the I2S peripheral and DMA. It works with the WS2811 / WS2812B / SK6812 family of devices with RGB or RGBW pixels.

Here’s a comparison of some alternatives for driving these strips:

• The ESP32 RMT LED Strip component uses the RMT peripheral to precisely control the timing of the output and ensure compatibility with a wide range of LED strips. However, there is only enough RMT symbol memory to buffer a few pixels at a time. Flickering may occur when the microcontroller is busy performing higher priority tasks and the RMT interrupt cannot be serviced soon enough to refill the buffer for subsequent pixels.
• This component, the I2S Clockless LED Strip, uses the I2S peripheral and DMA to drive the output with larger buffers that are more immune to flickering caused by interrupt latency. However, the resulting waveform diverges slightly from the datasheet timing recommendations although in practice it is close enough for the LED pixels to work reliably.

This table shows the number of I2S TDM ports available for this component on each ESP32 variant. Each LED strip uses one port. The original ESP32, ESP32-S2, and ESP32-C2 lack the necessary hardware and are not supported.

Variant	Ports
ESP32-C3	1
ESP32-C5	1
ESP32-C6	1
ESP32-C61	1
ESP32-H2	1
ESP32-H4	1
ESP32-P4	3
ESP32-S3	2

NOTE

This component may conflict with other uses of the I2S peripheral (such as for speakers and microphones).

# Example configuration entry
light:
  - platform: i2s_clockless_led_strip
    name: "My Light"
    pin: GPIOXX
    num_leds: 30
    channel_colors: GRB

Configuration variables

• pin (Required, Pin Schema): The pin for the data line of the light.
• num_leds (Required, int): The number of LEDs in the strip.
• channel_colors (Required, string): The order in which the strip expects its color channels. List each of R, G and B exactly once, optionally with a single W in any position; for example GRB, BGR, GRBW, WRGB or RWGB. The value is case-insensitive. Including a W makes this a four channel RGBW strip.
• All other options from Light.

See Also

• Light Component
• Power Supply Component
• API Reference: i2s_clockless_led_strip.h