DMOS Microsteppping Drivers have built-in translator.
Press Release Summary:
With output ratings of 35 V and 1.5 A, A3983 and A3984 operate bipolar stepper motors in full-, half-, quarter-, eighth- (A3983), and sixteenth- (A3984) step modes. They combine STEP and DIRECTION interface with 7.8 x 6.4 mm eTSSOP package and feature internal synchronous rectification control circuitry as well as fixed off-time PWM current regulator. Products also provide internal circuit protection.Original Press Release:
Allegro MicroSystems, Inc. Announces DMOS Microsteppping Drivers with Translator
Worcester, MA - April 20, 2005 - Allegro MicroSystems, Inc. announces the release of the A3983 and A3984, two new DMOS microstepping motor drivers with built-in translator and output ratings of 35 V and 1.5 A (2 A peak). They are designed to operate bipolar stepper motors in full-, half-, quarter-, eighth- (A3983), and sixteenth- (A3984) step modes. The devices combine an easy-to-use STEP and DIRECTION interface with a small eTSSOP package (7.8 x 6.4 mm), efficient high-current output, and high-resolution microstepping control at a truly competitive price.
The translator is key to the easy implementation of the A3983/84. By simply inputting one pulse on the STEP input, the motor will take one microstep. There are no phase-sequence tables, high-frequency control lines or complex interfaces to program. The simple, two-input STEP and DIRECTION interface of the A3983/84 makes it ideal for applications with multiple motors that would normally push the I/O capacity of most microprocessor controllers.
Internal synchronous rectification control circuitry is included in the A3983/84 to improve power dissipation during PWM operation. The power dissipation savings (typically greater than 20 percent) will result in lower temperature rise and eliminate the need for external Schottky diodes. Competitive devices with bipolar outputs cannot implement synchronous rectification.
The A3983/84 include a fixed off-time PWM current regulator that will automatically switch to slow- or mixed-decay modes. This patented current decay scheme results in reduced audible noise, increased step accuracy and reduced power dissipation. Internal circuit protection includes thermal shutdown with hysteresis, undervoltage lockout and crossover current protection. Special power-up sequencing is not required.
Targeted at the office automation, and industrial markets, the A3983/84 are manufactured using the Allegro® ABCD (Allegro Bipolar CMOS DMOS) process and are offered in an industry-standard 24-lead TSSOP package with exposed thermal pad (suffix 'LP'). Pricing is $1.94 per part for quantities of 10,000.
Allegro MicroSystems, Inc. is a supplier of advanced mixed-signal power semiconductors and Hall-effect sensors targeted toward the automotive, communications, computer/office automation, consumer and industrial markets. It maintains a leadership position in the integrated magnetic sensor and integrated motor driver product segments. With over 2,000 employees, Allegro is headquartered in Worcester, MA. Further information about Allegro, as well as free samples on our products, can be found at www.allegromicro.com.
