Pin Description

RX Pin

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

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

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

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.