CP2112 USB to I2C Debug Board

The CP2112 USB to I2C debug board is built around the Silicon Labs CP2112 USB to SMBus bridge. Plug it into a computer over USB and it appears as a standard HID device, so there are no drivers to install and no firmware to write. It gives your PC direct access to I2C and SMBus devices, which makes it a handy tool for testing sensors, reading and writing registers, and debugging a circuit before you write any microcontroller code. It also has 8 configurable GPIO lines, and it works on Windows, macOS and Linux.

Key Features

• USB 2.0 full-speed (12 Mbps) with integrated transceiver, so no external crystal or USB resistors are needed
• SMBus / I2C master with a configurable clock speed and a 512-byte data buffer
• Standard HID class device, so no custom driver is needed on Windows, macOS or Linux
• 8 GPIO pins, each configurable as input or output and as open-drain or push-pull
• Configurable clock output on a GPIO pin, from 48MHz down to 94kHz
• GPIO can drive an LED to show SMBus read and write activity
• USB suspend status available through a suspend pin
• One-time programmable ROM for custom USB product information such as VID, PID and strings
• On-chip power-on reset and voltage regulator (3.45V output)
• Free graphical configuration utility, plus HID-to-SMBus API libraries for Windows, macOS and Linux

Specifications

• Bridge IC: Silicon Labs CP2112
• USB: 2.0 full-speed, HID class
• USB bus power supply: 4.0V to 5.25V
• Self-powered supply (VDD): 3.0V to 3.6V
• I/O voltage: 1.8V to VDD
• Buffer: 512-byte SMBus data buffer
• GPIO: 8 pins, input/output, open-drain/push-pull
• Operating temperature: -40°C to 85°C

Pinout

• VCC: Power
• GND: Ground
• SDA: I2C data
• SCL: I2C clock
• WAK: Wake / suspend signal
• INT: Interrupt signal
• RST: Reset

Software and Compatibility

The CP2112 enumerates as a standard HID device, so it needs no driver installation. Silicon Labs provides a configuration utility for setting the SMBus clock speed, GPIO functions and USB descriptors, along with an HID-to-SMBus API library for Windows, macOS and Linux so you can write your own tools. Linux also has a built-in kernel driver that exposes the CP2112 as a standard I2C adapter.

Applications

• Testing and debugging I2C sensors and peripherals from a PC
• Reading and writing device registers during bring-up
• USB dongles and portable controllers
• Data logging and test equipment
• Medical meters, handheld controllers and point-of-sale products

Documentation

Download the CP2112 datasheet (PDF)

This product can be found here:

• Breakouts & Modules
• Communication Modules
• Power
• Prototyping