Data Sheet 29317.6* 2544 QUAD DARLINGTON POWER DRIVER OUT4 1 16 IN 4 K 2 15 IN3 OUT3 3 14 ENABLE GROUND 4 13 GROUND GROUND 5 12 GROUND OUT2 6 11 V CC K 7 10 IN 2 OUT1 8 9 IN 1 Dwg. PP-017A Combining logic gates and high-current bipolar outputs, the UDN2544B quad Darlington power driver provides an interface between low-level logic circuitry and high-power loads. Each of the four outputs can sink up to 1.8 A in the on state with peak inrush currents to 2.5 A. The four power outputs are each comprised of an opencollector Darlington driver and an internal flyback/clamp diode for switching inductive loads. They feature a minimum breakdown and sustaining voltage of 50 V. The logic inputs are compatible with TTL and 5 V CMOS logic systems. This device is particularly well-suited for unipolar stepper motor drive applications. With complementary control inputs and an activelow ENABLE, the UDN2544B makes it easy to implement full stepping of a stepper motor with only two microcontroller/microprocessor control lines. Other typical applications include relay or solenoid driving and incandescent or LED lamp driving. The UDN2544B is supplied in a 16-pin batwing power DIP. The batwing construction provides for maximum package power dissipation in a standard DIP construction. At 25°C, and with only 1 sq. in. of copper foil at the ground tabs, the package is capable of safely dissipating 3.8 W. FEATURES ■ 1.8 A Continuous Output Current ■ Output Voltage to 50 V ■ Inputs Configured for Unipolar Stepper Motors ■ Active-Low Output Enable ABSOLUTE MAXIMUM RATINGS at TA = 25°C Output Voltage, VOUT ............................. 50 V Output Current, IOUT (Peak) ........................................... 2.5 A (Continuous) ................................. 1.8 A Logic Supply Voltage, VCC .................... 7.0 V Input Voltage, VIN .................................. 7.0 V Package Power Dissipation, PD ......................................... See Graph Operating Temperature Range, TA .................................. -20°C to +85°C Storage Temperature Range, TS ................................ -55°C to +150°C ■ TTL and 5 V CMOS Compatible Inputs ■ Integral Transient-Suppression Diodes Always order by complete part number: UDN2544B . 2544 QUAD DARLINGTON POWER DRIVER ELECTRICAL CHARACTERISTICS at TA = +25°C, TJ ≤ 150°C, VCC = 4.75 V to 5.25 V. Limits Characteristic Symbol Output Leakage Current ICEX Output Sustaining Voltage Output Saturation Voltage Input Voltage Input Current Total Supply Current Clamp Diode Forward Voltage Clamp Diode Leakage Current Test Conditions Min. Typ. Max. Units VOUT = 50 V — <1.0 100 µA VCE(sus) IOUT = 1.8 A, L = 3.0 mH 50 — — V VCE(SAT) IOUT = 600 mA — 0.9 1.0 V IOUT = 1.0 A — 1.0 1.2 V IOUT = 1.8 A — 1.3 1.6 V Logic 1 VIN(1) or VEN(1) 2.4 — — V Logic 0 VIN(0) or VEN(0) — — 0.8 V Logic 1 VIN(1) or VEN(1) = 2.4 V — — 10 µA Logic 0 VIN(0) or VEN(0) = 0.8 V — — -100 µA ICC All Outputs ON, Outputs Open — 14 20 mA All Outputs OFF — 0.4 2.0 mA IF = 1.0 A — 1.3 1.6 V IF = 1.8 A — 1.6 2.0 V VR = 50 V — < 1.0 100 µA VF IR Typical Data is for design information only. Negative current is defined as coming out of (sourcing) the specified terminal. As used here, -100 is defined as greater than +10 (absolute magnitude convention) and the minimum is implicitly zero. TRUTH TABLE IN1 OUT1 IN2 OUT2 IN3 OUT3 IN4 OUT4 L H L ON OFF H L OFF ON H L OFF ON H L ON OFF X OFF X OFF X OFF X OFF H X = Don't care 5 ALLOWABLE PACKAGE POWER DISSIPATION IN WATTS ENABLE RθJT = 6.0°C/W 4 3 2 R θJA = 43°C/W 1 0 25 50 75 100 TEMPERATURE IN °C 125 150 Dwg. GP-010B 115 Northeast Cutoff, Box 15036 W Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1989, 1995 Allegro MicroSystems, Inc. 2544 QUAD DARLINGTON POWER DRIVER TYPICAL APPLICATION (UNIPOLAR STEPPER MOTOR WITH ZENER FLYBACK) Dwg. EP-015 TRUTH TABLE INPUTS 1/2 3/4 L L H H H L L H A ON OFF OFF ON APPLICATIONS INFORMATION WINDINGS B C ON ON OFF OFF D OFF ON ON OFF OFF OFF ON ON A Zener diode can be used to increase the flyback voltage. The increased flyback voltage gives a much faster inductive load turn-OFF current decay resulting in improved motor performance. The maximum Zener voltage, plus the load supply voltage, plus the flyback diode forward voltage must not exceed the device’s rated sustaining voltage. OUTPUT VOLTAGE VBB + VZ + VF V BB V BB + VF With external control circuitry, the ENABLE input (active low) can be used for chopper (PWM) applications. If the ENABLE input is not used, it should be tied low. All inputs will float high if open circuited. VOUT(SAT) OUTPUT CURRENT A typical application is shown driving a four-phase unipolar stepper motor. Note that with the complimentary control inputs, only two logic signals are needed to drive the motor in the two-phase format. The two phase drive format illustrated, energizes two adjacent phases in each detent position (AB, BC, CD, DA) to provide an improved torque-speed product and greater detent torque. ZENER CLAMP DIODE CLAMP Dwg. WP-001 Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the design of its products. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use. 2544 QUAD DARLINGTON POWER DRIVER Dimensions in Inches (controlling dimensions) 16 0.020 0.008 9 NOTE 4 0.430 MAX 0.280 0.240 0.300 BSC 1 0.070 0.045 0.100 0.775 0.735 8 0.005 BSC MIN 0.210 MAX 0.015 0.150 0.115 MIN 0.022 0.014 Dwg. MA-001-17A in Dimensions in Millimeters (for reference only) 16 0.508 0.204 9 NOTE 4 10.92 MAX 7.11 6.10 7.62 BSC 1 1.77 1.15 2.54 19.68 18.67 BSC 8 0.13 MIN 5.33 MAX 0.39 3.81 2.93 MIN 0.558 0.356 Dwg. MA-001-17A mm NOTES: 1. Leads 1, 8, 9, and 16 may be half leads at vendor’s option. 2. Lead thickness is measured at seating plane or below. 3. Lead spacing tolerance is non-cumulative. 4. Webbed lead frame. Leads indicated are internally one piece. 5. Exact body and lead configuration at vendor’s option within limits shown. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000