DFRobot
Gravity: CH423 I2C 24 Digital IO Expansion Module
The Gravity CH423 I2C 24 Digital IO Expansion Module extends your microcontroller with 24 additional digital output/input pins over a standard I2C connection...
The Gravity CH423 I2C 24 Digital IO Expansion Module extends your microcontroller with 24 additional digital output/input pins over a standard I2C connection. Based on the CH423 chip, it provides 8 GPIOs with interrupt support and 16 dedicated GPOs.
The built-in current drive circuit delivers up to 15 mA continuous current per pin, allowing it to statically drive 24 LED tubes or dynamically drive up to 128 LEDs — making it well suited for LED matrix displays, light cubes, and indicator arrays.
Key Features
- 24 Digital Pins – 8 GPIO (with interrupt) + 16 GPO
- Built-In Current Drive – Up to 15 mA continuous per pin
- I2C Interface – Gravity-compatible 4-pin connector
- Wide Voltage Range – 3.3 V to 5 V supply
- LED Drive Capability – Static drive for 24 LEDs or dynamic drive for up to 128 LEDs
Specifications
- Chip: CH423
- Power Supply: 3.3–5 V
- Static Current: 1 mA
- IO Continuous Drive Current: 15 mA
- Interface: I2C
- I2C Address Range: 0x20–0x3F (occupies the full range; cannot share with other I2C devices at these addresses)
- Operating Temperature: −20 °C to +80 °C
- Board Size: 45 mm × 37 mm (1.78″ × 1.46″)
Ideal For
- LED tube and dot matrix displays
- Light cubes and LED arrays
- GPIO expansion for pin-limited microcontrollers
- Indicator panels and control systems
Package Contents
- 1× Gravity CH423 I2C 24 Digital IO Expansion Module
- 1× Gravity 4-pin I2C/UART sensor cable
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- GPIO
- General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.
- Gravity
- Gravity is DFRobot’s plug-in connector system for sensors, motors and modules, using standard cables to reduce loose jumper wiring. It matters because Gravity-compatible parts can connect directly to these ports, while non-Gravity parts may need adapters or manual wiring.
- I2C
- I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.
- I2C address
- An I2C address is the number a device uses so a microcontroller can tell it apart from other devices on the same I2C bus. It matters because two devices with the same fixed address may conflict if used together.
- LED
- A light-emitting diode is a small electronic component that lights up when current flows through it in the correct direction. In this kit, LEDs create the flashing effect, so polarity and correct soldering matter for the project to work.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
- UART
- UART is a simple serial connection that sends data over separate transmit and receive wires, often labelled TX and RX. It matters because this module is designed to replace a wired UART cable with a wireless link while keeping the same serial data format.
Find this product in
Brands
Supplier page — dfrobot.com
Supplier Description · 792.4 KB · Click any page to view full size
Related Tutorials
Free guides on learn.littlebird.com.au
