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# Pin Description

<figure><img src="https://109307382-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fh0Bx45jrwZ9AeD35UCuD%2Fuploads%2FulsjZwZW0fo5IWQQvZvg%2Fimage.png?alt=media&amp;token=d85781f6-a27f-42fb-933b-49f6d3de4084" alt=""><figcaption></figcaption></figure>

### RX Pin <a href="#refheading___toc23978_752506811" id="refheading___toc23978_752506811"></a>

DMX UART Receiver Pin.

This pin receives DMX512 data from an RS485 receiver or transceiver. It operates at 3.3V and it is 5 V tolerant.

Use an RS485 receiver or transceiver (e.g., THVD1400) to convert DMX (RS485) differential signals to TTL voltage levels. See Hardware Examples section for more details.

Important: Connecting this pin directly to DMX bus without the receiver or transceiver will permanently damage the device.

### LEDS Pin <a href="#refheading___toc7979_1730400282" id="refheading___toc7979_1730400282"></a>

Addressable LEDs Output Pin, Open-Collector.

This pin outputs the data that will get into the addressable LED data input (DIN) pin.

The pin is open-collector, and since most addressable LEDs expect 5 V logic, it should be pulled up to 5 V with a 500 Ω resistor. Using a lower resistor value will generate a stronger data signal. The minimum admissible value for this resistor is 250 Ω; going below this may cause permanent damage to the device. A value of 500 Ω is recommended and provides a strong and reliable signal, while environments with long cable runs or electrical noise may benefit from a slightly lower value.

### ACT Pin <a href="#refheading___toc7981_1730400282" id="refheading___toc7981_1730400282"></a>

DMX Activity Pin.

The usage of this pin is optional. A standard LED (typically green, with series resistor) can be connected to indicate DMX activity. When DMX data is detected on the RX pin, this pin toggles between 0 V and 3.3 V, causing the LED to blink.

If unused, it is recommended to pull this pin down to GND with a 10 kΩ resistor.

### TYPE Pin <a href="#refheading___toc23984_752506811-copy-1" id="refheading___toc23984_752506811-copy-1"></a>

Addressable LED Type Selection Pin.

* Connect to GND for 3 color addressable LEDs. In this case 170 LEDs will be addressed (512 channels ÷ 3 colors).
* Connect to VDD for 4 color addressable LEDs. In this case 128 LEDs will be addressed (512 channels ÷ 4 colors).

This pin can be changed during operation. It features an internal weak pull-down resistor.


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