The shield contains two L293D motor drivers and one 74HC595 shift register. The shift register expands 3 pins of the Arduino to 8 pins to control the direction for the motor drivers. The output enable of the L293D is directly connected to PWM outputs of the Arduino.
To increase the maximum current, the L293D allows extra chips with “piggyback”. Piggyback is soldering one or two or three extra L293D drivers on top of the L293D drivers on the board to increase the maximum current. The L293D allows parallel operation.
The Motor Shield is able to drive 2 servo motors, and has 8 half-bridge outputs for 2 stepper motors or 4 full H-bridge motor outputs or 8 half-bridge drivers, or a combination.
– Multi-functional, easy operation
– Coudl drive 4CH DC motor/2CH stepper motor, and could drive 2CH servo at the same time
– Support the newest Arduino UNO, Arduino Mega 2560
– Two 5V servo motor ports, connect to Arduino high resolution timer (no dither)
– Up to four two-way DC motor and 4-channel PWM speed regulation (0.5% resolution)
– Up to two stepping motors positive & negative control, Single/double step control
– 4-channel H-bridge: L293D chip provides each bridge 0.6A current and with thermal power-off protection, 4.5V to 36V; Big wire connection terminal posts (10-22AWG);
– With Arduino reset button;
– Compatible with Mega, Diecimila, Duemilanove