A3966SLB

Data Sheet 29319.25A† 3966 A3966SLB OUT1A PHASE 1 ENABLE 1 GROUND SENSE1 OUT 1B LOAD SUPPLY REFERENCE 1 V 2 3 4 5 6 7 8 V V BB VCC RC LOGIC LOGIC BB DUAL FULL-BRIDGE PWM MOTOR DRIVER The A3966SA and A3966SLB are designed to drive both windings of a two-phase bipolar stepper motor. Each device includes two H-bridges capable of continuous output currents of ±650 mA and operating voltages to 30 V. Motor winding current can be controlled by the internal fixed-frequency, pulse-width modulated (PWM), current-control circuitry. The peak load current limit is set by the user’s selection of a reference voltage and current-sensing resistors. Except for package style and pinout, the two devices are identical. The fixed-frequency pulse duration is set by a user-selected external RC timing network. The capacitor in the RC timing network also determines a user-selectable blanking window that prevents false triggering of the PWM current-control circuitry during switching transitions. To reduce on-chip power dissipation, the H-bridge power outputs have been optimized for low saturation voltages. The sink drivers feature Allegro’s patented Satlington™ output structure. The Satlington outputs combine the low voltage drop of a saturated transistor and the high peak current capability of a Darlington. For each bridge, a PHASE input controls load-current polarity by selecting the appropriate source and sink driver pair. For each bridge, an ENABLE input, when held high, disables the output drivers. Special powerup sequencing is not required. Internal circuit protection includes thermal shutdown with hysteresis, ground-clamp and flyback diodes, and crossovercurrent protection. The A3966SA is supplied in a 16-pin dual in-line plastic package. The A3966SLB is supplied in a 16-lead plastic SOIC with copper heat sink tabs. The power tab is at ground potential and needs no electrical isolation. 16 15 14 13 12 11 10 9 OUT 2A PHASE 2 ENABLE 2 GROUND SENSE 2 OUT 2B LOGIC SUPPLY RC REF Dwg. PP-066-1 ABSOLUTE MAXIMUM RATINGS Load Supply Voltage, VBB ...................... 30 V Output Current, IOUT (peak) ........... ±750 mA (continuous) .............................. ±650 mA Logic Supply Voltage, VCC .................... 7.0 V Input Voltage, Vin ........ -0.3 V to VCC + 0.3 V Sense Voltage, VS ................................ 1.0 V Package Power Dissipation (TA = 25°C), PD A3966SA ..................................... 2.08 W* A3966SLB ................................... 1.87 W* Operating Temperature Range, TA ..................................... -20°C to +85°C Junction Temperature, TJ .................................................. +150°C Storage Temperature Range, TS ................................... -55°C to +150°C 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 a junction temperature of 150°C. * Per SEMI G42-88 Specification, Thermal Test Board Standardization for Measuring Junction-to-Ambient Thermal Resistance of Semiconductor Packages. FEATURES I I I I I I I I ±650 mA Continuous Output Current 30 V Output Voltage Rating Internal Fixed-Frequency PWM Current Control Satlington™ Sink Drivers User-Selectable Blanking Window Internal Ground-Clamp & Flyback Diodes Internal Thermal-Shutdown Circuitry Crossover-Current Protection and UVLO Protection Always order by complete part number: Part Number A3966SA A3966SLB Package 16-pin DIP 16-lead batwing SOIC RθJA 60°C/W 67°C/W RθJC 38°C/W — RθJT — 6°C/W 3966 DUAL FULL-BRIDGE PWM MOTOR DRIVER FUNCTIONAL BLOCK DIAGRAM OUT 1A OUT 1B V CC PHASE 1 V BB PHASE 2 + LOGIC SUPPLY OUT 2A OUT 2B LOAD SUPPLY UVLO & TSD CONTROL LOGIC1 CONTROL LOGIC2 UVLO & TSD ENABLE 1 SOURCE ENABLE 1 ENABLE 2 CURRENT-SENSE COMPARATOR 1 SENSE 1 SENSE 2 CURRENT-SENSE COMPARATOR 2 PWM LATCH 1 R Q S BLANKING GATE 1 + – + – BLANKING GATE 2 PWM LATCH 2 R Q S ÷4 OSC RC R1S R 2S SOURCE ENABLE 2 GROUND RT CT REFERENCE Dwg. FP-036-6 A3966SA SENSE 1 OUT 1B LOAD SUPPLY REFERENCE RC LOGIC SUPPLY OUT 2B SENSE 2 1 LOGIC TRUTH TABLE 16 15 14 ENABLE 1 PHASE 1 OUT 1A GROUND GROUND OUT 2A PHASE 2 ENABLE 2 2 3 4 5 6 7 8 V REF RC V PHASE X H L ENABLE H L L OUTA Off H L OUTB Off L H V BB 13 12 11 X = Irrelevant CC LOGIC 10 9 Dwg. PP-066-2 2 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1998, 2000 Allegro MicroSystems, Inc. 3966 DUAL FULL-BRIDGE PWM MOTOR DRIVER ELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 30 V, VCC = 4.75 V to 5.5 V, VREF = 2 V, VS = 0 V, 56 kΩ & 680 pF RC to Ground (unless noted otherwise) Limits Characteristic Output Drivers Load Supply Voltage Range Output Leakage Current VBB ICEX Operating, IOUT = ±650 mA, L = 3 mH VOUT = 30 V VOUT = 0 V Output Saturation Voltage VCE(SAT) Source Driver, IOUT = -400 mA Source Driver, IOUT = -650 mA Sink Driver, IOUT = +400 mA, VS = 0.5 V Sink Driver, IOUT = +650 mA, VS = 0.5 V Clamp Diode Forward Voltage VF IF = 400 mA IF = 650 mA Motor Supply Current (No Load) IBB(ON) IBB(OFF) VENABLE1 = VENABLE2 = 0.8 V VENABLE1 = VENABLE2 = 2.4 V VCC — — — — — — — — — — —