A3918: Low Voltage DC Motor Driver

Designed for pulse width modulated (PWM) control of a low voltage DC motor, the A3918 is capable of output currents up to 1.5 A and operating voltages from 2.5 to 9 V.

The A3918 has an internal fixed off-time PWM timer that sets a peak current based on the selection of a current sense resistor. An overcurrent output flag is provided that notifies the user when the current in the motor winding reaches the peak current determined by the sense resistor. The fault output does not affect driver operation.

The A3918 is provided in a 16-contact, 3 mm × 3 mm, 0.75 mm nominal overall height QFN, with exposed pad for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin leadframe plating.

Applications include the following:

• Digital still cameras (DSC)
• Cell phone cameras
• USB powered devices
• Battery powered devices

• 2.5 to 9 V operation
• Internal PWM current control
• Synchronous rectification for reduced power dissipation
• Peak current output flag
• Undervoltage lockout
• 低的R_DS(on)outputs
• Small package
• Brake mode for DC motor
• Sleep function
• Crossover-current protection
• Thermal shutdown