A4982 DMOS Microstepping Driver with Translator And Overcurrent Protection Features and Benefits Description Low R outputs The A4982 is a complete microstepping motor driver with DS(ON) Automatic current decay mode detection/selection built-in translator for easy operation. It is designed to operate Mixed and Slow current decay modes bipolar stepper motors in full-, half-, quarter-, and sixteenth-step Synchronous rectification for low power dissipation modes, with an output drive capacity of up to 35 V and 2 A. Internal UVLO The A4982 includes a fixed off-time current regulator which Crossover-current protection has the ability to operate in Slow or Mixed decay modes. 3.3 and 5 V compatible logic supply The ET package meets customer requirements for no smoke Thin profile QFN and TSSOP packages no fire (NSNF) designs by adding no-connect pins between Thermal shutdown circuitry critical output, sense, and supply pins. So, in the case of a Short-to-ground protection pin-to-adjacent-pin short, the device does not cause smoke Shorted load protection or fire. Additionally, the device does not cause smoke or fire Low current Sleep mode, < 10 A when any pin is shorted to ground or left open. No smoke no fire (NSNF) compliance (ET package) The translator is the key to the easy implementation of the A4982. Simply inputting one pulse on the STEP input drives Packages: 32-contact QFN the motor one microstep. There are no phase sequence tables, with exposed thermal pad high frequency control lines, or complex interfaces to program. 5 mm 5 mm 0.90 mm Approximate size The A4982 interface is an ideal fit for applications where a (ET package) complex microprocessor is unavailable or is overburdened. During stepping operation, the chopping control in the A4982 automatically selects the current decay mode, Slow or Mixed. In Mixed decay mode, the device is set initially to a fast decay for a proportion of the fixed off-time, then to a slow decay for 24-pin TSSOP with exposed thermal pad the remainder of the off-time. Mixed decay current control (LP Package) Continued on the next page Typical Application Diagram V 0.1 F0.1 F DD 0.22 F VREG ROSC CP1 CP2 VCP VBB1 0.22 F VDD 100 F VBB2 5 k Microcontroller or SLEEP OUT1A Controller Logic A4982 OUT1B STEP SENSE1 MS1 MS2 DIR OUT2A ENABLE OUT2B RESET SENSE2 VREF GND GND 4982-DS Rev. 1DMOS Microstepping Driver with Translator A4982 And Overcurrent Protection Description (continued) results in reduced audible motor noise, increased step accuracy, Special power-on sequencing is not required. and reduced power dissipation. The A4982 is supplied in two surface mount package, the ET, a Internal synchronous rectification control circuitry is provided 5 mm 5 mm, 0.90 mm nominal overall package height QFN to improve power dissipation during PWM operation. Internal package, and the LP package, a 24-pin TSSOP. Both packages have circuit protection includes: thermal shutdown with hysteresis, exposed pads for enhanced thermal dissipation, and are lead (Pb) free (suffix T), with 100% matte tin plated leadframes. undervoltage lockout (UVLO), and crossover-current protection. Selection Guide Part Number Package Packing A4982SETTR-T 32-pin QFN with exposed thermal pad 1500 pieces per 7-in. reel A4982SLPTR-T 24-pin TSSOP with exposed thermal pad 4000 pieces per 13-in. reel Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Load Supply Voltage V 35 V BB Output Current I 2 A OUT Logic Input Voltage V 0.3 to 5.5 V IN Logic Supply Voltage V 0.3 to 5.5 V DD VBBx to OUTx 35 V Sense Voltage V 0.5 V SENSE Reference Voltage V 5.5 V REF Operating Ambient Temperature T Range S 20 to 85 C A Maximum Junction T (max) 150 C J Storage Temperature T 55 to 150 C stg Allegro MicroSystems, Inc. 2 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000 www.allegromicro.com