A4970

A4970 Dual Full-Bridge PWM Motor Driver Features and Benefits ▪ 750 mA continuous output current ▪ 45 V output sustaining voltage ▪ Internal clamp diodes ▪ Internal PWM current control ▪ Low output saturation voltage ▪ Internal thermal shutdown circuitry ▪ Pin compatible with UDx2916 ▪ DMOS outputs Description The A4970 motor driver drives both windings of a bipolar stepper motor or bidirectionally controls two DC motors. Both bridges are capable of sustaining 45 V and include internal pulse-width modulation (PWM) control of the output current to 750 mA. For PWM current control, the maximum output current is determined by user selection of a reference voltage and sensing resistor. Two logic-level inputs select output current limits of 0%, 33%, 67%, or 100% of the maximum level. A PHASE input to each bridge determines load current direction. Intrinsic diodes in the MOSFET output structure protect against inductive transients. Internally generated delays prevent crossover currents when switching current direction. Special power-up sequencing is not required. Thermal protection circuitry disables the outputs if the chip temperature exceeds safe operating limits. The device is supplied in a 24-pin surface-mount wide SOIC with two pairs of batwing leads (LB). The webbed-pin construction provides for maximum package power dissipation in the smallest possible construction. The package is lead (Pb) free, with 100% matte tin leadframe plating. Package: 24-pin batwing wide SOIC (package LB) Not to scale PWM Current-Control Circuitry VBB 24 Channel 1 pin numbers shown. VREF 10 M 17 14 OUTA OUTB 16 E I 13 0 I1 12 Divide by 1, 1.5, or 3 10 SENSE – 15 + ONE SHOT 9 RC SOURCE DISABLE RC RS C C RT CT A4970CDS, Rev. 1 A4970 Dual Full-Bridge Motor Driver Selection Guide Part Number A4970GLBTR-T A4970SLBTR-T Package 24-pin batwing SOICW 24-pin batwing SOICW Packing 1000 per reel 1000 per reel Ambient Temperature (°C) –40 to 105 –20 to 85 Absolute Maximum Ratings Characteristic Motor Supply Voltage Logic Supply Voltage Input Voltage Reference Input Voltage Output Emitter Voltage Sense Voltage Symbol VBB VCC VIN VREF VE VSENSE Peak Output Current* IOUT Continuous Package Power Dissipation Operating Ambient Temperature Maximum Junction Temperature Storage Temperature PD TA TJ(max) Tstg See graph Range G Range S Output current rating may be limited by duty cycle, ambient temperature, and heat sinking. Under any set of conditions, do not exceed the specified current rating or TJ(max) I0x, I1x, PHASEx pins VREF pin Notes Rating 45 6.0 –0.3 to 6.0 –0.3 to 8.0 750 750 1.0 750 — –40 to 105 –20 to 85 150 –55 to 150 Units V V V V mV mV A mA W ºC ºC ºC ºC Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 2 A4970 Dual Full-Bridge Motor Driver Power Dissipation 5 ALLOWABLE PACKAGE POWER DISSIPATION IN WATTS R JT = 6.0°C/W 4 3 2 1 RJA = 55°C/W* 0 25 50 75 100 TEMPERATURE IN °C 125 150 *Measured on a single-layer board, with 1 sq. in. of 2 oz copper area. For additional information, refer to the Allegro Web site. Pin-out Diagram I 02 I 12 PHASE 2 V REF 2 RC 2 GROUND GROUND LOGIC SUPPLY RC 1 V REF 1 PHASE 1 I 11 1 2 3 4 5 6 VBB PWM 2 24 23 22 21 20 19 18 17 16 15 PWM 1 LOAD SUPPLY OUT2B SENSE 2 E2 OUT 2A GROUND GROUND OUT1A E1 SENSE 1 OUT1B I 01 θ2 7 8 9 9 10 11 12 θ1 V CC 14 13 Allegro MicroSystems, Inc. 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000; www.allegromicro.com 3 A4970 Dual Full-Bridge Motor Driver ELECTRICAL CHARACTERISTICS Valid at TA = 25°C, TJ ≤ 150°C, VBB = 45 V, VCC = 4.75 to 5.25 V, VREF = 5.0 V, unless otherwise noted Characteristics Output Drivers (OUTA or OUTB) Motor Supply Range Output Leakage Current Output MOSFET On Resistance Clamp Diode Leakage Current Clamp Diode Forward Voltage Driver Supply Current Control Logic Input Voltage Input Current Reference Voltage Range Reference Input Current Current Limit Threshold Thermal Shutdown Temperature Total Logic Supply Current Fixed Off-Time VCC Undervoltage Lockout (UVLO) Threshold VCC Undervoltage Lockout (UVLO) Threshold VIN(1) VIN(0) IIN(1) VREF IREF VREF/ VSENSE TJ ICC(ON) ICC(OFF) toff VCCUVLO VCCUVLOHYS I0 = I1 = 0.8 V, no load I0 = I1 = 2.4 V, no load RT = 56 kΩ, CT = 820 pF VCC rising All inputs All inputs VIN = 2.4 V VIN = 0.8 V Operating VREF = 7.5 V I0 = I1 = 0.8 V I0 = 2.4 V, I1 = 0.8 V I0 = 0.8 V, I1 = 2.4 V 2.4 – – – 1.5 – 9.5 13.5 25.5 – – – 42 – – – –