Compatible with the Arduino line of products. Trademark registrations throughout the world for ARDUINO or Arduino® are owned by: Arduino AG and Arduino SA.
Instead of a L293D driver, we now have the TB6612 MOSFET driver: with 1.2A per channel and 3A peak current capability. It also has much lower voltage drops across the motor so you get more torque out of your batteries, and there are built-in flyback diodes as well.
Instead of using a latch and the for Arduino's PWM pins, we have a fully-dedicated PWM driver chip onboard. This chip handles all the motor and speed controls over I2C. Only two pins (SDA & SCL) are required to drive the multiple motors, and since it's I2C you can also connect any other I2C devices or shields to the same pins. This also makes it drop-in compatible with any for Arduino.
Completely stackable design: 5 address-select pins means up to 32 stackable shields: that's 64 steppers or 128 DC motors! What on earth could you do with that many steppers? I have no idea but if you come up with something send us a photo because that would be a pretty glorious project.
Tested compatible with for Arduino UNO, for Leonardo, for ADK/Mega R3, Due, Diecimila & Duemilanove. Works with Mega/ADK R2 and earlier with 2 wire jumpers.
Resources
DatasheetLibrary
Sample Code
Tutorial