MINI USB Host Shield 2.0 ADK - Support Google Android ADK

Product Overview

The MINI USB Host Shield 2.0 ADK is a compact Arduino USB host interface based on the MAX3421E controller. Designed primarily for 3.3V microcontrollers (e.g., Arduino Pro Mini, FTDI), it enables USB host functionality including keyboard, mouse, U-disk, camera support, and Android ADK compatibility. It even supports USB hub operation when used with the appropriate library.

Electrical & Interface Specifications

• Controller IC: MAX3421E USB Host Controller
• Operating Voltage: 3.3V DC (you can use a logic level shifter module for 5V)
• Communication with MCU: SPI interface (MOSI, MISO, SCK, SS, IRQ)
• USB Port: Type-A female connector
• USB Host Features: Supports USB 2.0 Full-Speed devices (up to 12 Mb/s); compatible with keyboards, mice, flash drives, and cameras; Android Open Accessory (ADK) support (e.g., Nexus One, Nexus S, Droid X); USB hub capability via USB Host Shield Library 2.0

Compatibility & Requirements

This usb host shield arduino module targets:

• Arduino Pro Mini (3.3V/8MHz)
• 3.3V FTDI breakout boards

Fully compatible with the USB Host Shield Library 2.0 (founded by Oleg Mazurov / felis).

Mechanical Details

• Dimensions: 38 × 18 mm
• Weight: ~4.5 g
• Form Factor: Designed to stack onto Pro Mini or be used as an SPI breakout

Key Features

• Compact USB Host Module — ideal for adding USB support in space-limited projects
• 3.3V Logic — safe for 3.3V MCUs (Pro Mini, FTDI), preventing level-shifting issues
• USB OTG/ADK Ready — enables Arduino to act as an Android accessory using the ADK protocol
• USB Hub Support — can manage multiple USB devices via a hub
• SPI-Based Design — compatible with standard SPI pins and libraries
• Open Source — includes schematic, EAGLE files, and Arduino library examples

Typical Use Cases

• Adding USB device support (e.g., flash drives, keyboards) to Arduino for data logging
• Building Android accessory applications, such as game controllers or IoT endpoints
• Integrating camera or sensor devices via USB into Arduino systems
• Designing compact USB-host equipped projects with limited board space

Technical Summary

Integration Tips

• Ensure your Arduino runs at 3.3V — a 5V MCU requires level-shifting or voltage-adjustment. Our Logic Level Converter (Bi-Directional 3.3V/5V) handles this conversion safely between a 5V board like an Uno or Mega and this 3.3V shield.
• For projects shifting more than one signal line at once, the TXS0108E 8-Channel Logic Level Converter is also compatible with 3.3V/5V systems.
• Include the USB Host Shield 2.0 library in your project for plug-and-play example code.
• For Android ADK: use the provided sample APK and firmware sources.
• If using USB hubs, power the hub adequately to avoid enumeration failures.

Frequently Asked Questions

Can I use this shield directly with a standard 5V Arduino Uno or Mega?

Not directly — this shield operates at 3.3V. To use it safely with a 5V board like the Uno or Mega, you'll need a logic level converter between the two.

What is the MAX3421E chip used for on this board?

The MAX3421E is the USB host controller that gives the Arduino the ability to act as a USB host, letting it communicate with USB devices like keyboards, flash drives, and Android devices via the ADK protocol.

Does this shield support USB hubs?

Yes, USB hub functionality is supported through the USB Host Shield Library 2.0, letting you connect multiple USB devices at once.

What Android devices are compatible with this shield's ADK support?

It supports Android Open Accessory (ADK) on Android 2.3.4+ phones and 3.1+ tablets, including devices like the Nexus One, Nexus S, and Droid X.

Do I need any special library to use this shield?

Yes, the USB Host Shield Library 2.0 (by Oleg Mazurov / felis) provides the example code and driver support needed to get started.

Browse our full Arduino Boards & Shields collection for more compatible boards and accessories for your Arduino USB host project.