A3901 Dual Full Bridge Low Voltage Motor Driver Features and Benefits Description ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ The A3901 is a dual full-bridge motor driver, designed for low voltage portable applications involving bipolar stepper or brush dc motors. The outputs have been optimized for low voltage drop, with currents up to ±400 mA (±800 mA with outputs paralleled) and an operating voltage range of 2.5 to 5.5 V. Low RDS(on) outputs Full- and half-stepping capability Small package Forward, reverse, and brake modes for dc motors Sleep mode with zero current drain PWM control up to 250 kHz Crossover-current protection Thermal shutdown (TSD) The four inputs (IN1 to IN4) can control a bipolar stepper motor in full- or half-step mode, or dc motors in forward, reverse, or brake mode. The inputs can be PWMed for current or speed control at frequencies up to 250 kHz. Internal protection circuitry includes thermal shut down (TSD) and crossover (shoot-through) protection. Package: 10 Contact DFN/MLP (suffix EJ) The A3901 is supplied in a 3 x 3 x 0.75 mm nominal, 10-lead DFN/MLP package, with exposed thermal pad (package “EJ”). This small footprint package is lead (Pb) free, with 100% matte tin leadframe plating. Approximate Scale 1:1 Typical Application +VBAT 10 µF 10 V VBB OUT1 IN1 M IN2 OUT2 A3901 CPU IN3 OUT3 IN4 OUT4 GND Figure 1. Typical stepper motor control +VBAT +VBAT 10 µF 10 V 10 µF 10 V VBB OUT1 IN1 OUT2 OUT2 A3901 CPU IN3 OUT3 M IN4 M IN2 A3901 IN3 OUT1 IN1 M IN2 CPU VBB OUT3 IN4 OUT4 GND Figure 2. Typical dual dc motor control 3901-DS OUT4 GND Figure 3. Typical single dc motor control (paralleled outputs) A3901 Dual Full Bridge Low Voltage Motor Driver Selection Guide Part Number A3901SEJTR-T Packing Tape and reel, 1500 pieces/reel Absolute Maximum Ratings Parameter Symbol Conditions Min. Typ. Max. Units Load Supply Voltage VBB – – 7 V Output Current per Channel* IOUT – – 400 mA Logic Input Voltage Range VIN –0.3 – 6 V Junction Temperature TJ – – 150 °C Storage Temperature Range TS –40 – 150 °C Operating Temperature Range TA –20 – 85 °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. Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 2 A3901 Dual Full Bridge Low Voltage Motor Driver Functional Block Diagram VBB 10 µF 10 V BRIDGE1 TSD OUT1 OUT2 IN1 IN2 Control Logic and Gate Drive BRIDGE2 IN3 OUT3 IN4 OUT4 PAD GND Terminal Diagram Number 1 2 3 4 5 6 7 8 9 10 – Name IN1 IN2 GND IN3 IN4 OUT4 OUT3 VBB OUT2 OUT1 Pad IN1 1 IN2 2 GND 3 IN3 IN4 10 OUT1 9 OUT2 8 VBB 4 7 OUT3 5 6 OUT4 PAD Description Logic input 1 Logic input 2 Ground terminal Logic input 3 Logic input 4 Bridge2 output to load Bridge2 output to load Load supply terminal Bridge1 output to load Bridge1 output to load Exposed pad for thermal dissipation; connect to GND externally Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 3 A3901 Dual Full Bridge Low Voltage Motor Driver ELECTRICAL CHARACTERISTICS at TA =25°C, and VBB = 2.5 to 5.5 V, unless noted otherwise Characteristics Symbol Test Conditions Source driver, VBB = 3 V, IOUT = 300 mA Source driver, VBB = 5 V, IOUT = 300 mA Output On Resistance RDS(on) Sink driver, VBB = 3 V, IOUT = 300 mA Sink driver, VBB = 5 V, IOUT = 300 mA Clamp Diode I = 300 mA All outputs PWMed at 20 kHz Sleep mode, VBB= 3 V Motor Supply Current IBB Sleep mode, VBB= 5 V Logic Input Voltage VIN(1) VIN(0) Logic Input Current Input Voltage Hysteresis Propagation Delay Crossover Delay Thermal Shut Down Temperature Thermal Shut Down Hysteresis Min. – – – – – – – – VBB/2 Typ. 1.8 1.2 1.2 0.8 – 0.6 – <50 – Max. 2.1 1.4 1.4 1.0 1.5 – 100 500 – Units Ω Ω Ω Ω V mA nA nA V – – 0.5 V IIN(1) IIN(0) Vhys VIN = 2.0 V VIN = 0.5 V – – – tpd(on) Input Low to Sink On, Input High to Source On – 130 – ns tpd(off) tCOD TJ TJhys Input High to Sink Off, Input Low to Source Off – – – – 50 80 150 10 – – – – ns ns °C °C <100 500 <–100 –500 150 – nA nA mV THERMAL CHARACTERISTICS Characteristics Package Thermal Resistance* *Additional Rating Unit Measured on 4-layer board based on JEDEC standard 45 °C/W Measured on 2-layer board with copper limited to solder pads and 0.88 in2. of copper on each side 65 °C/W Symbol RθJA Test Conditions thermal information is available on the Allegro Web site. Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 4 A3901 Dual Full Bridge Low Voltage Motor Driver Motor Operation Truth Table INx1 OUT12 OUT2 OUT3 OUT4 Stepper Motor IN1 IN2 IN3 IN4 0 0 0 0 OFF OFF OFF OFF 1 0 1 0 H L H L 0 0 1 0 OFF OFF H L 0 1 1 0 L H H L 0 1 0 0 L H OFF OFF 0 1 0 1 L H L H 0 0 0 1 OFF OFF L H 1 0 0 1 H L L H 1 0 0 0 H L OFF OFF DC Motor (Dual) IN1 or IN3 IN2 or IN4 0 0 OFF OFF OFF OFF 1 0 H L H L 0 1 L H L H 1 1 L L L L DC Motor (Single, Paralleled) IN1 and IN3 IN2 and IN4 0 0 OFF OFF OFF OFF 1 0 H L H L 0 1 L H L H 1 1 L L L L DC Motor (External PWM) IN1 or IN3 IN2 or IN4 1 0 H L H L 0 0 OFF OFF OFF OFF 0 1 L H L H 0 0 OFF OFF OFF OFF 1 0 H L H L 1 1 L L L L 0 1 L H L H 1 1 L L L L 10 = logic low, V < V ; 1 = logic high, V > V INx IN(0)(max) INx IN(1)(min) 2H = voltage high, source driver on; L = voltage low, sink driver on Function Full Stepping Sleep Mode Step 1 – Step 2 – Step 3 – Step 4 – Half-Stepping Sleep Mode Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Step 7 Step 8 Hi-Z (Sleep Mode)/Coast Forward Reverse Brake Hi-Z (Sleep Mode)/Coast Forward Reverse Brake Forward Fast Decay Reverse Fast Decay Forward Slow Decay Reverse Slow Decay Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 5 A3901 Dual Full Bridge Low Voltage Motor Driver Characteristic Performance Output On Resistance versus Load Supply Voltage IOUT = 100 mA Output On Resistance versus Load Supply Voltage IOUT = 300 mA 4.00 4.00 Source 3.50 Source 3.50 Sink Sink 3.00 Total RDS(on) (Ω) RDS(on) (Ω) 3.00 2.50 2.00 2.50 2.00 1.50 1.50 1.00 1.00 0.50 0.50 2.5 3.0 3.5 4.0 4.5 2.5 5.0 Total 3.0 3.5 4.0 4.5 VBB (V) Output On Resistance versus Output Current VBB = 3 V Output On Resistance versus Output Current VBB = 5 V 3.50 3.50 3.00 3.00 Source Source 2.50 Sink RDS(on) (Ω) RDS(on) (Ω) 5.0 VBB (V) Total 2.00 1.50 1.00 2.50 Sink Total 2.00 1.50 1.00 0.50 0.50 100 150 200 250 VBB (V) 300 350 400 100 150 200 250 300 350 400 VBB (V) Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 6 A3901 Dual Full Bridge Low Voltage Motor Driver Functional Description Device Operation. The A3901 is a dual full-bridge low voltage motor driver capable of operating one stepper motor or up to two dc motors. MOSFET output stages substantially reduce the voltage drop and the power dissipation of the outputs of the A3901 compared to typical drivers with bipolar transistors. Internal circuit protection includes thermal shutdown with hysteresis, clamp diodes, and crossover current protection. The A3901 is designed for portable applications with a power-off (Sleep mode) current of 50 nA typical, and an operating voltage of 2.5 to 5.5 V. The A3901 logic inputs are 3 to 5 V logic compatible. Output current can be regulated by pulse width modulating (PWM) the inputs. The full-bridge outputs can be paralleled for higher-current applications (see figure 6). In conditions where the logic supply voltage drops below 2.5 V, both the sink and the source RDS(on) will increase beyond the specified values. In extreme cases, no power will be delivered to the motor(s). However, the device will not be damaged. In stepping operation, the device can drive in either full- or half-step mode. The stepping mode is set by the signal pattern on the INx terminals, as shown in the stepping timing diagrams. External PWM. Pulse width modulating the inputs allows the output current to be regulated. Slow decay mode is achieved by holding one input high while PWMing the other input. Holding one input low and PWMing the other input results in fast decay. See the External PWM diagram. Sleep Mode. Pulling all inputs to 0.5 V or less, sends the A3901 into Sleep mode, during which it draws 50 nA typical. Thermal Shutdown. The A3901 will disable the outputs if the junction temperature reaches 165°C. When thermal shutdown is entered, after the junction temperature drops 15°C, the outputs will be re-enabled. Brake Mode. When driving dc motors, the A3901 will go into Brake mode (turn on both sink drivers) when all inputs, INx, are logic 1. There is no protection during braking, so care must be taken to ensure that the peak current during braking does not exceed the absolute maximum current. Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 7 A3901 Dual Full Bridge Low Voltage Motor Driver Application Information VBB TSD IN1 OUT1 IN2 OUT2 CONTROL LOGIC/ GATE DRIVE GND VBB 10 µF/10 V IN3 OUT3 IN4 OUT4 Stepper Motor Figure 4a. Typical stepper motor control application IN1 IN2 IN3 IN4 +VBB/Rmotor IOUT1-2 0A –VBB/Rmotor +VBB/Rmotor IOUT3-4 0A –VBB/Rmotor Figure 4b. Full step mode timing chart IN1 IN2 IN3 IN4 +VBB/Rmotor IOUT1-2 0A –VBB/Rmotor +VBB/Rmotor IOUT3-4 0A –VBB/Rmotor Figure 4c. Half step mode timing chart Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 8 A3901 Dual Full Bridge Low Voltage Motor Driver VBB TSD IN1 OUT1 IN2 OUT2 GND CONTROL LOGIC/ GATE DRIVE DC Motor VBB 10 µF/10 V IN3 OUT3 IN4 OUT4 DC Motor Figure 5. Typical dual dc motor control application. Either IN1 or IN2 can be used to drive OUT1 and OUT2. Either IN3 or IN4 can be used to drive OUT3 and OUT4. VBB TSD IN1 OUT1 IN2 OUT2 GND IN3 IN4 CONTROL LOGIC/ GATE DRIVE DC Motor VBB 10 µF 10 V OUT3 OUT4 Figure 6. Typical single dc motor control (paralleled outputs) Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com 9 A3901 Dual Full Bridge Low Voltage Motor Driver IN1/3 IN2/4 +VBB/Rmotor +(VBB–VBEMF)/Rmotor IOUT1-2/3-4 0A –(VBB–VBEMF)/Rmotor –VBB/Rmotor Forward Brake Reverse Coast Figure 7. Typical dual dc motor control application IN1/3 IN2/4 +IREG IOUT1-2/3-4 0A –IREG Forward/ Fast Decay Reverse/ Fast Decay Forward/ Slow Decay Reverse/ Slow Decay Figure 8. External PWM current control in fast and slow decay modes 10 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com A3901 Dual Full Bridge Low Voltage Motor Driver Package EJ, 10-contact DFN/MLP 3.15 .124 2.85 .112 A B 10 Preliminary dimensions, for reference only (reference JEDEC MO-229 WEED) Dimensions in millimeters U.S. Customary dimensions (in.) in brackets, for reference only Dimensions exclusive of mold flash, gate burrs, and dambar protrusions Exact case and lead configuration at supplier discretion within limits shown 3.15 .124 2.85 .112 A A Terminal #1 mark area B Exposed thermal pad (reference dimensions only, terminal #1 identifier appearance at supplier discretion) C Reference pad layout (reference IPC7351 SON50P300X300-11WEED3N); adjust as necessary to meet application process requirements; when mounted on multilayer PCBs, thermal vias at the exposed thermal pad land can improve thermal dissipation (reference EIA/JEDEC Standard JESD51-5) 1 2 10X SEATING PLANE 0.08 [.003] C 10X 0.30 .012 0.18 .007 0.80 .031 0.70 .028 0.10 [.004] M C A B 0.05 [.002] M C 0.30 .012 NOM 0.20 .008 REF 0.50 .020 0.50 .020 NOM 0.85 .033 NOM 1 C C 0.05 .002 0.00 .000 2 0.225 x 0.225 .009 x .009 REF 1.64 .065 NOM 0.20±0.05 .008±.002 MIN 2.90 .114 NOM 0.50 .020 0.30 .012 B 1.64 .065 NOM 10 2.38 .094 NOM 2.38 .094 NOM The products described herein are manufactured under one or more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283; 5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719; 5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents pending. 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 performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the information being relied upon is current. Allegro products are not authorized for use as critical components in life-support devices or systems without express written approval. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringement of patents or other rights of third parties which may result from its use. Copyright©2005, 2006 Allegro MicroSystems, Inc. 11 Allegro MicroSystems, Inc. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 www.allegromicro.com