Data Sheet29319.1*FULL-BRIDGE PWM MOTOR DRIVERDesigned for bidirectional pulse-width modulated current control ofinductive loads, the A3952S– is capable of continuous output currentsto ±2 A and operating voltages to 50 V. Internal fixed off-time PWMcurrent-control circuitry can be used to regulate the maximum loadcurrent to a desired value. The peak load current limit is set by theuser’s selection of an input reference voltage and external sensingresistor. The fixed OFF-time pulse duration is set by a user-selectedexternal RC timing network. Internal circuit protection includes thermalshutdown with hysteresis, transient suppression diodes, and crossover-current protection. Special power-up sequencing is not required.With the ENABLE input held low, the PHASE input controls loadcurrent polarity by selecting the appropriate source and sink driver pair.The MODE input determines whether the PWM current-control circuitryoperates in a slow current-decay mode (only the selected sink driverswitching) or in a fast current-decay mode (selected source and sinkswitching). A user-selectable blanking window prevents false triggeringof the PWM current control circuitry. With the ENABLE input held high,all output drivers are disabled. A sleep mode is provided to reducepower consumption when inactive.When a logic low is applied to the BRAKE input, the brakingfunction is enabled. This overrides ENABLE and PHASE to turn OFFboth source drivers and turn ON both sink drivers. The brake functioncan be safely used to dynamically brake brush dc motors.The A3952S– is supplied in a choice of four power packages. In allpackage styles, the batwing/power tab is at ground potential and needsno isolation. These devices are also available for operation from -40°Cto +125°C. To order, change the suffix from 'S–' to 'K–'.FEATURES■ ±2 A Continuous Output Current Rating■ 50 V Output Voltage Rating■ Internal PWM Current Control■ Fast and Slow Current-Decay Modes■ Sleep (Low Current Consumption) Mode■ Internal Transient Suppression Diodes■ Under-Voltage Lockout■ Internal Thermal Shutdown Circuitry■ Crossover-Current ProtectionAlways order by complete part number: Part Number Package RθJARθJTA3952SB 16-Pin DIP 43°C/W 6.0°C/WA3952SEB 28-Lead PLCC 42°C/W 6.0°C/WA3952SLB 16-Lead SOIC 67°C/W 6.0°C/WA3952SW 12-Pin Power-Tab SIP 36°C/W 2.0°C/WA3952SBNote that the A3952SB (DIP) and the A3952SLB(SOIC) are electrically identical and share acommon terminal number assignment.ABSOLUTE MAXIMUM RATINGSLoad Supply Voltage, VBB .................. 50 VOutput Current, IOUT(tw ≤ 20 µs).................................. ±3.5 A(Continuous) ............................... ±2.0 ALogic Supply Voltage, VCC................. 7.0 VLogic Input Voltage Range,VIN....................... -0.3 V to VCC + 0.3 VSense Voltage, VSENSE...................... 1.5 VReference Voltage, VREF.................... 15 VPackage Power Dissipation,PD ....................................... See GraphOperating Temperature Range,TA ............................... –20°C to +85°CJunction Temperature, TJ ............. +150°C*Storage Temperature Range,TS ............................. –55°C to +150°COutput current rating may be limited by duty cycle,ambient temperature, heat sinking and/or forcedcooling. Under any set of conditions, do notexceed the specified current rating or a junctiontemperature of +150°C.* Fault conditions that produce excessive junctiontemperature will activate device thermal shutdowncircuitry. These conditions can be tolerated butshould be avoided.3952MODEGROUNDGROUNDLOGICSUPPLYPHASE GROUND GROUNDRCSENSELOADSUPPLYDwg. PP-056BRAKEREFLOADSUPPLYVCCOUTBOUTAVBBVBBLOGICENABLE123456789101112131415163952FULL-BRIDGEPWM MOTOR DRIVER115 Northeast Cutoff, Box 15036Worcester, Massachusetts 01615-0036 (508) 853-5000VBBRCVCCLOGICSUPPLYLOADSUPPLYPHASEEMITTERSUVLO& TSDRSDwg. FP-036MODEREFOUTAOUTBENABLESENSE–+BRAKE9RRINPUT LOGICGROUNDQRS1.5 VPWM LATCHVCC+ –BLANKINGSLEEP &STANDBY MODESVTH'EB' ONLY'B', 'LB', & 'W'PACKAGESRTCTFUNCTIONAL BLOCK DIAGRAMTRUTH TABLEBRAKE ENABLE PHASE MODE OUTAOUTBDESCRIPTIONH H X H Z Z Sleep ModeH H X L Z Z Standby, Note 1H L H H H L Forward,Fast-Decay ModeH L H L H L Forward,Slow-Decay ModeH L L H L H Reverse,Fast-Decay ModeH L L L L H Reverse,Slow-Decay ModeL X X H L L Brake,Fast-Decay ModeL X X L L L Brake, No CurrentControl, Note 2X = Irrelevant Z = High Impedance (source and sink both OFF)NOTES: 1. Includes active pull-offs for power outputs.2. Includes internal default Vsense level for over-current protection.50 75 100 125 150106420TEMPERATURE IN °C825Dwg. GP-007-1AALLOWABLE PACKAGE POWER DISSIPATION IN WATTS'W' TAB'B' , 'EB', & 'LB' TAB'W' AMBIENT'B' & 'EB' AMBIENT'LB' AMBIENTCopyright © 1994 Allegro MicroSystems, Inc.3952FULL-BRIDGEPWM MOTOR DRIVERA3952SEB A3952SWELECTRICAL CHARACTERISTICS at TA = +25°C, VBB = 50 V, VCC = 5.0 V, VBRAKE = 2.0 V,VSENSE = 0 V, RC = 20 kΩ/1000 pF to Ground (unless noted otherwise).LimitsCharacteristic Symbol Test Conditions Min. Typ. Max. UnitsOutput DriversLoad Supply Voltage Range VBBOperating, IOUT = ±2.0 A, L = 3 mH VCC– 50 VOutput Leakage Current ICEXVOUT = VBB– <1.0 50 µAVOUT = 0 V – <-1.0 -50 µAOutput Saturation Voltage VCE(SAT)Source Driver, IOUT = -0.5 A – 0.9 1.2 VSource Driver, IOUT = -1.0 A – 1.0 1.4 VSource Driver, IOUT = -2.0 A – 1.2 1.8 VSink Driver, IOUT = +0.5 A – 0.9 1.2 VSink Driver, IOUT = +1.0 A – 1.0 1.4 VSink Driver, IOUT = +2.0 A – 1.3 1.8 VClamp Diode Forward Voltage VFIF = 0.5 A – 1.0 1.4 V(Source or Sink) IF = 1.0 A – 1.1 1.6 VIF = 2.0 A – 1.4 2.0 VLoad Supply Current IBB(ON)VENABLE = 0.8 V – 2.9 6.0 mA(No Load) IBB(OFF)VENABLE = 2.0 V, VMODE = 0.8 V – 3.1 6.5 mAVBRAKE = 0.8 V – 3.1 6.5 mAIBB(SLEEP)VENABLE = VMODE = 2.0 V – <1.0 50 µA12345 678 9101112GROUNDDwg. PP-058MODELOGICSUPPLYPHASERCSENSEREFLOADSUPPLYOUTBOUTAENABLEVCCVBBLOGICBRAKE12345678910111213141516171819202122232425262728GROUNDGROUNDGROUNDGROUNDDwg. PP-057 NOCONNECTION EMITTERSRCLOADSUPPLYREFVCCVBBLOGICBRAKELOGICSUPPLYPHASEENABLEMODESENSELOADSUPPLYOUTBOUTAContinued next page …3952FULL-BRIDGEPWM MOTOR DRIVER115 Northeast Cutoff, Box 15036Worcester, Massachusetts 01615-0036 (508) 853-5000Control LogicLogic Supply Voltage Range VCCOperating 4.5 5.0 5.5 VLogic Input Voltage VIN(1)2.0 ––VVIN(0)––0.8 VLogic Input Current IIN(1)VIN = 2.0 V – <1.0 20 µAIIN(0)VIN = 0.8 V – <-2.0 -200