UDN2916A

UDN2916A STEPPER MOTOR DRIVER ADVANCE DATA ABLE TO DRIVE BOTH WINDINGS OF BIPOLAR STEPPER MOTOR OUTPUT CURRENT UP TO 750mA EACH WINDING WIDE VOLTAGE RANGE 10V TO 50V HALF-STEP, FULL-STEP AND MICROSTEPPING MODE BUILT-IN PROTECTION DIODES INTERNAL PWM CURRENT CONTROL LOW OUTPUT SATURATION VOLTAGE DESIGNED FOR UNSTABILIZED MOTOR SUPPLY VOLTAGE INTERNAL THERMAL SHUTDOWN DESCRIPTION The UDN2916A is a bipolar monolithic integrated circuits intended to control and drive both winding of a bipolar stepper motor or bidirectionally control two DC motors. The UDN2916A with a few external components form a complete control and drive circuit for LSTTL or microprocessor controlled stepper motor system. The power stage is a dual full bridge capable of sustaining 50V and including four diodes for current recirculation. BLOCK DIAGRAM Powerdip 20+2+2 ORDERING NUMBER: UDN2916A A cross conduction protection is provided to avoid simultaneous cross conduction during switching current direction. An internal pulse-width-modulation (PWM) controls the output current to 750mA with peak startup current up to 1A. Wide range of current control from 750mA (each bridge) is permitted by means of two logic inputs and an external voltage reference. A phase input to each bridge determines the load current direction. A thermal protection circuitry disables the outputs if the chip temperature exceeds safe operating limits. November 1991 ThAdvanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice. 1/8 UDN2916A PIN CONNECTION (Top view) PIN FUNCTIONS N° 1;2 3;23 4;22 Name OUTPUT A SENSE RESISTOR COMPARATOR INPUT See pins 5;21 Connection to Lower Emitters of Output Stage for Insertion of Current Sense Resistor Input connected to the comparators. The voltage across the sense resistor is feedback to this input throught the low pass filter RC CC. The higher power transistors are disabled when the sense voltage exceeds the reference voltage of the selected comparator. When this occurs the current decays for a time set by RT C T (toff = 1.1 RT CT). See fig. 1. Output Connection. The output stage is a ”H” bridge formed by four transistors and four diodes suitable for switching applications. See pins 7;18 Ground Connection. With pins 6 and 19 also conducts heat from die to printed circuit copper. See INPUT 1 (pins 9;17) These pins and pins 8;20 (INPUT 0) are logic inputs which select the outputs of the comparators to set the current level. Current also depends on the sensing resistor and reference voltage. See Funcional Description. This TTL-compatible logic inputs sets the direction of current flow through the load. A high level causes current to flow from OUTPUT A (source) to OUTPUT B (sink). A schmitt trigger on this input provides good noise immunity and a delay circuit prevents output stage short circuits during switching. A voltage applied to this pin sets the reference voltage of the comparators, this determining the output current (also thus depending on Rs and the two inputs INPUT 0 and INPUT 1). A parallel RC network connected to this pin sets the OFF time of the higher power transistors. The pulse generator is a monostable triggered by the output of the comparators (toff = 1.1 RT CT). Supply Voltage Input for Logic Circuitry Supply Voltage Input for the Output Stages. Function 5;21 6;19 7;18 8;20 9;17 OUTPUT B GROUND GROUND INPUT 0 INPUT 1 10;16 PHASE 11;15 REFERENCE VOLTAGE 12;14 RC 13 24 2/8 Vss - LOGIC SUPPLY VS - LOAD SUPPLY UDN2916A ABSOLUTE MAXIMUM RATINGS Symbol VS Io Io VSS VIN Vsense TJ Top Tstg Supply Voltage Output Current (peak) Output Current (continuous) Logic Supply Voltage Logic Input Voltage Range Sense Output Voltage Junction Temperature Operating Temperature Range Storage Temperature Range Parameter Value 50 ±1 ±0.75 7 -0.3 to +7 1.5 +150 0 to 70 -55 to +150 Unit V A A V V V °C °C °C THERMAL DATA Symbol Description Max Max Value 14 60 Unit °C/W °C/W R thj-case Thermal Resistance Junction-case R thj-ambient Thermal Resistance Junction-ambient ELECTRICAL CHARACTERISTICS (Tamb = 25°C, Ttab ≤ 70°C, VS = 50V, VSS = 4.75V to 5.25V, VREF = 5V; unless otherwise specified) See fig. 3. Symbol Parameter Test Condition Min. Typ. Max. Unit OUTPUT DRIVERS (OUTA or OUTB) VS ICEX VCE(sat) Motor Supply Range Output Leakage Current Output Saturation Voltage VOUT = Vs VOUT = 0 Sink Driver, IOUT = +500mA Sink Driver, IOUT = +750mA Source Driver, IOUT = -500mA Source Driver, IOUT = -750mA VR = 50V Sink Diode Source Diode IF =750mA Both Bridges ON, No Load Both Bridges OFF 10