The A3906 integrated circuit from Allegro MicroSystems (www.allegro.com) consists of a single-step motor control or double low-voltage DC motor control for operation with voltages from 2.5 to 9 V. The circuit has an internal current limit PWM and peak output current warning. In addition, its outputs are low rds9on) for less dissipation and it has the “brake” mode for DC motors. In the figure below we have the application circuit for two common DC motors. The resistor values depend on the application and more information on their calculation can be obtained from the datasheet available on the Allegro website. For the control of a stepper motor, the configuration is shown in the figure at the bottom. In sleep mode the device enters the low power condition. The maximum output current for both circuits is 1 A and the component can be obtained in a 20-contact QFN enclosure with an exposed pad to aid in heat dissipation.
