IC drives two stepper motors or four DC motors
Able to drive two stepper motors or four DC motors, the A5988 quad DMOS full-bridge driver IC has been introduced by Allegro MicroSystems Europe. Each full-bridge output is rated up to 1.6A and 40V. The A5988 includes fixed off-time PWM current regulators, along with 2-bit nonlinear DACs that allow stepper motors to be controlled in full, half, and quarter steps and DC motors in forward, reverse and coast modes.
The PWM current regulator uses the Allegro patented mixed decay mode for reduced audible motor noise, increased step accuracy and reduced power dissipation. The A5988 is targeted at the consumer and office automation markets with end applications to include CCTV (pan and tilt) applications, scanners, POS, laser, inkjet and label printers.
Internal synchronous rectification control circuitry is provided to improve power dissipation during PWM operation. A low power sleep mode is included to reduce power dissipation. Protection features include thermal shutdown with hysteresis, undervoltage lockout and crossover-current and over-current protection. Special power-up sequencing is not required.
The A5988 is supplied in two packages, EV and JP, with exposed power tabs for enhanced thermal performance. The EV is a 6x6mm, 36-pin QFN package with a nominal overall package height of 0.90mm. The JP is a 7x7mm 48-pin LQFP. Both packages are lead (Pb) free, with 100% matt-tin leadframe plating.