Kappa3750Ard: IS3750 Demoboard for Arduino

The Kappa3750Ard is an evaluation board for the IS3750 Addressable LED Controller chip. It allows engineers to easily evaluate the IS3750 without needing to solder or develop a custom prototype, offering a convenient, ready-to-use solution. The board includes 36 WS2813 RGB LEDs.

Designed as a shield using the Arduino form factor, the Kappa3750Ard takes advantage of its wide adoption, ensuring compatibility with various microcontroller boards (not included), such as Arduino and STM32 Nucleo boards.

The IS3750 is an ideal solution for meeting addressable LED protocol timing constraints. It reduces CPU load and eliminates the need for dedicated GPIOs by operating over the I2C interface.

How It Works

The core of the shield is the IS3750 Addressable LED Controller Chip. Its I2C pins are routed directly to the Arduino’s I2C interface. So, by simply plugging the shield into your evaluation board, it connects seamlessly to its I2C serial interface.

The board includes I2C pull-up resistors, so you don’t need to add them externally. It also features a jumper to select the I2C voltage level based on your Arduino board. The IS3750 operates at 3.3V and is 5V tolerant on its I2C pins. Another jumper lets you select the appropriate I2C speed.

The LED output pin of the IS3750 is connected to a voltage level shifter to ensure a proper 5V signal level, since the chip itself operates at 3.3V.

Controlling the LEDs is super easy. The IS3750 uses an internal memory map:

• Registers 0x001, 0x002, and 0x003 control the RGB values of the first LED.
• Registers 0x004, 0x005, and 0x006 control the second LED, and so on.

Think of it like writing to EEPROM—except instead of storing data, you’re writing colors!