Gravity: CH423 I2C 24 Digital IO Expansion Module

The Gravity CH423 I2C 24 Digital IO Expansion Module expands a microcontroller's interface capabilities by providing 24 additional digital ports over a simple I2C connection. It is an ideal expansion board for makers, educators, and hobbyists building interactive displays, matrix panels, or complex lighting projects that exceed standard pin counts.

Versatile digital pin breakout

The expansion board provides 24 digital ports in total, broken out into 8 general-purpose input/output pins with interrupt functionality and 16 dedicated general-purpose output pins.

Built-in LED drive circuitry

Featuring an integrated current drive circuit delivering up to 15mA continuous driving current per IO, the module can statically drive 24 LED tubes or dynamically drive up to 128 individual LEDs.

Ideal for visual display projects

Thanks to its high output channel count and robust current handling, this board is well suited for controlling dot matrix screens, light cubes, and multi-segment LED assemblies.

I2C interface and electrical ratings

The module operates across a 3.3V to 5V power supply range with a low 1mA static current. It communicates via I2C across the 0x20 to 0x3F address space and functions within an operating temperature range of -20 to 80 degrees Celsius.

Compact layout and included accessories

Measuring 45 by 37 mm, the module includes a standard Gravity 4-pin I2C/UART sensor cable for immediate plug-and-play wiring to compatible development boards.

Downloads & documentation

• Product wiki (DFRobot)