A4973 Full-Bridge PWM Motor Driver FEATURES AND BENEFITS DESCRIPTION 1.5 A continuous output current Designed for bidirectional pulse-width-modulated (PWM) 50 V output voltage rating current control of inductive loads, the A4973 is capable of 3 to 5.5 V logic supply voltage continuous output currents to 1.5 A and operating voltages Internal PWM current control to 50 V. Internal fixed off-time PWM current control circuitry Fast and slow current decay modes can be used to regulate the maximum load current to a desired Sleep (low current consumption) mode value. The peak load current limit is set by the users selection Internal transient-suppression diodes of an input reference voltage and external sensing resistor. The Internal thermal shutdown circuitry fixed off-time pulse duration is set by a user-selected external Crossover current and UVLO protection RC timing network. Internal circuit protection includes thermal shutdown with hysteresis, transient suppression diodes, and crossover current protection. Special power-up sequencing is PACKAGES: not required. With the ENABLE input held low, the PHASE input controls load current polarity by selecting the appropriate source and sink driver pair. The MODE input determines whether the PWM current control circuitry operates in a slow current decay mode (only the selected source driver switching) or in a fast current decay mode (selected source and sink switching). A user-selectable blanking window prevents false triggering of the PWM current control circuitry. With the ENABLE input Package B, 16-pin DIP Package LB, 16-pin SOIC held high, all output drivers are disabled. A sleep mode is with exposed tabs with internally fused pins provided to reduce power consumption. Not to scale Continued on the next page Functional Block Diagram LOGIC 6 V 9 10 15 CC 16 SUPPLY SLEEP & STANDBY MODES 14 MODE V BB PHASE 7 UVLO & TSD 8 ENABLE 1 BRAKE PWM LATCH 11 R SENSE 2 Q S R BLANKING S GROUND V 4 CC 12 RC + 5 3 2 13 REF GROUND V TH C T R T 4973DS, Rev. 5 January 29, 2019 MCO-0000192 INPUT LOGIC LOAD SUPPLY OUT A OUT B LOAD SUPPLY +A4973 Full-Bridge PWM Motor Driver DESCRIPTION (CONTINUED) When a logic low is applied to the BRAKE input, the braking 16-pin dual in-line plastic package with copper heat-sink tabs, function is enabled. This overrides ENABLE and PHASE to turn and a 16-pin plastic SOIC with copper heat-sink tabs. For both off both source drivers and turn on both sink drivers. The brake package styles, the power tab is at ground potential and needs no function can be used to dynamically brake brush DC motors. electrical isolation. Each package type is available in a lead (Pb) The A4973 is supplied in a choice of two power packages: a free version (100% matte-tin-plated leadframe). SELECTION GUIDE Part Number Package Packing A4973SB-T * 16-pin DIP with exposed thermal tabs 25 pieces per tube A4973SLBTR-T 16-pin SOICW with internally-fused pins 1000 pieces per reel * A4973SB-T is no longer in production. The device should not be purchased for new design applications. Samples are no longer available. Date of status change: July 2, 2018. For existing customer transition, and for new customers or new applications, use A4973SLBTR-T. ABSOLUTE MAXIMUM RATINGS Characteristic Symbol Notes Rating Units Load Supply Voltage V 50 V BB Logic Supply Voltage V 6 V CC Logic/Reference Input Voltage Range V 0.3 to 6 V IN Sense Voltage V 0.5 V SENSE Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. Under any set of conditions, do Output Current, Continuous I 1.5 A OUT not exceed the specified current rating or a junction tempera - ture of 150C. Transient Output Current I t < 2 s 6 A OUT W Package Power Dissipation P See graph (p. 3) W D Operating Ambient Temperature T Range S 20 to 85 C A Fault conditions that produce excessive junction temperature Maximum Junction Temperature T (max) will activate the devices thermal shutdown circuitry. These 150 C J conditions can be tolerated but should be avoided. Storage Temperature T 55 to 150 C stg 2 Allegro MicroSystems, LLC 955 Perimeter Road Manchester, NH 03103-3353 U.S.A. www.allegromicro.com