Allegro MicroSystems A3981
The A3981 can be controlled by simple Step and Direction inputs, or through the SPI-compatible serial interface that also can be used to program many of the integrated features and to read diagnostic information. The current regulator can be programmed to operate in fixed off-time or fixed frequency PWM, with several decay modes to reduce audible motor noise and increase step accuracy. The current in each phase of the motor is controlled through a DMOS full bridge, using synchronous rectification to improve power dissipation.| Part No. | A3981 |
|---|---|
| Datasheet | A3981 Download |
| Manufacturer |  Allegro MicroSystems |
| Description | Automotive Programmable Stepper Driver |
| Buy | Stock & Price |
FEATURES AND BENEFITS
● Peak motor current up to ±1.4 A, 28 V● Low RDS(on) outputs, 0.5 Ω source and sink, typical
● Automatic current decay mode detection/selection
● Mixed, Fast, and Slow current decay modes
● Synchronous rectification for low power dissipation
● Internal OVLO, UVLO, and Thermal Shutdown circuitry
● Crossover-current protection
● Short-circuit and open-load diagnostics
● Hot and cold thermal warning
● Stall detect features
● SPI-compatible or simple Step and Direction motion control
● Highly configurable via SPI-compatible serial interface
APPLICATIONS
● Automotive stepper motors● Engine management
● Headlamp positioning PACKAGE: 28-Pin TSSOP with Exposed Thermal Pad (suffix LP) Not to scale
DESCRIPTION
TheA3981 is a flexible microstepping motor driver with built-in translator for easy operation. It is a single-chip solution, designed to operate bipolar stepper motors in full-, half-, quarter- and sixteenth-step modes, at up to 28 V and ±1.4 A. In addition the phas...
