Ordering number : EN7633A LB1945D Monolithic Digital IC PWM Current Control http://onsemi.com Stepping Motor Driver Overview The LB1945D is a PWM current control stepping motor driver that uses a bipolar drive technique. It is optimal for use with the carriage and paper feed stepping motors used in printers. Functions and Features • PWM current control (external clock) • Digital load current selection function (supports 1-2, W1-2, and 2-phase excitation) • Built-in high and low side diodes • Simultaneous on state prevention function (through-current prevention) • Built-in thermal shutdown circuit • Noise canceling function Specifications Absolute Maximum Ratings at Ta = 25°C Parameter Symbol Motor supply voltage VBB max Output peak current IO peak Output continuous current Logic system supply voltage Conditions tW ≤ 20μs Ratings Unit 30 V 1.0 A IO max 0.8 A VCC max 6.0 V Logic input voltage range VIN -0.3 to VCC V Emitter output voltage range VE 1.0 V Allowable power dissipation Pd max 2.8 W Operating temperature Topr Independent IC -20 to +90 °C Storage temperature Tstg -55 to +150 °C Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. Semiconductor Components Industries, LLC, 2013 June, 2013 41107 TI PC B8-6489, 6394 No.7633-1/9 LB1945D Recommended Operating Range at Ta = 25°C Parameter Symbol Motor supply voltage Conditions Ratings Unit VBB 10 to 28 V Logic system supply voltage VCC 4.75 to 5.25 V Reference voltage VREF 1.5 to 5.0 V Electrical Characteristics at Ta = 25°C, VBB = 24V, VCC = 5V, VREF = 5V Parameter Symbol Ratings Conditions min typ Unit max Output block IBB ON IBB OFF I1 = 0.8V, I2 = 0.8V, ENABLE = 0.8V Output saturation voltage 1 VO sat1 IO = +0.5A, sink side 0.3 0.5 V Output saturation voltage 2 VO sat2 IO = +0.8A, sink side 0.5 0.7 V Output saturation voltage 3 VO sat3 IO = -0.5A, source side 1.6 1.8 V VO sat4 IO = -0.8A, source side 1.8 2.0 V 50 μA Output stage supply current Output saturation voltage 4 Output leakage current Output sustain voltage 0.5 1.0 2.0 ENABLE = 3.2V mA 0.2 VO1(leak) VO2(leak) VO = VBB, sink side VO = 0V, source side -50 VSUS L = 3.9mH, IO = 1.0A* 30 I1 = 0.8V, I2 = 0.8V, ENABLE = 0.8V 50 70.0 92 7 10.0 13 V Logic block ICC ON ICC OFF Logic supply current ENABLE = 3.2V VIH VIL Input voltage Input current mA 3.2 V 1.8 IIH VIH = 3.2V VIL = 0.8V IIL 35 50 65 7 10 13 Set current control threshold VREF/ I1 = 0.8V, I2 = 0.8V 9.5 10 10.5 value VSEN I1 = 3.2V, I2 = 0.8V 13.5 15 16.5 I1 = 0.8V, I2 = 3.2V 25.5 30 34.5 25 32.5 μA μA Reference current IREF VREF = 5.0V, I1 = 0.8V, I2 = 0.8V 17.5 CR pin current ICR CR = 1.0V -1.0 Thermal shutdown temperature TS 170 °C TSHY 40 °C Thermal shutdown hysteresis μA *: The design specification items are design guarantees and are not measured. Package Dimensions unit:mm (typ) 3147C Pd max – Ta 15 12.7 11.2 R1.7 0.4 8.4 28 1 14 20.0 4.0 4.0 26.75 (1.81) 1.78 0.6 Allowable power dissipation, Pd max – W 3.5 3.0 2.8 2.5 2.0 1.5 1.34 1.0 0.5 0 -20 1.0 Independent IC 0 20 40 60 80 100 Ambient temperature, Ta – °C SANYO : DIP28H(500mil) No.7633-2/9 LB1945D 21 GND 22 VREF1 23 IA1 D-GND 24 IA2 E1 25 ENABLE1 SUBGND 26 PHASE1 NC 27 VCC OUTA 28 VBB OUTA Pin Assignment 20 19 18 17 16 15 9 10 11 12 13 14 S-GND VREF2 IB1 IB2 ENABLE2 8 CR 7 D-GND 6 E2 5 VBB 4 SUBGND 3 NC OUTB 2 OUTB 1 PHASE2 LB1945D Top view ILB01555 Pin Functions Pin No. Pin 22 VBB1 5 VBB2 24 E1 6 E2 27 OUTA 28 OUTA 2 OUTB 1 OUTB Description Output stage power supply voltage High side diode cathode connection The set current is controlled by inserting resistors RE between these pins and ground. Output pins 15 GND 14 S-GND Ground Sense ground 4, 25 SUBGND IC sub-ground 23 D-GND Low side built-in diode ground (anode side) 7 8 CR Chopping is performed at the period of a triangle wave set by the RC circuit connected to this pin. The triangle wave off time is the noise cancellation time. 16 VREF1 13 VREF2 Output current settings. 20 PHASE1 Output phase switching inputs 9 PHASE2 High-level input: OUTA = high, OUTA = low 19 ENABLE1 Output on/off control inputs 10 ENABLE2 High-level input: Output off 17, 18 IA1, IA2 Output current setting digital inputs. 12, 11 IB1, IB2 The output current is set to 1/3, 2/3 or 1 by input high/low levels to these pins. 21 VCC (The output current is determined by providing an input in the range 1.5V to 5V.) Low-level input: OUTA = low, OUTA = high Low-level input: Output on Logic block power supply voltage No.7633-3/9 LB1945D S-GND SUBGND VREF2 IB2 IB1 ENABLE2 PHASE2 VCC Block Diagram Current selection circuit Control logic circuit VBB2 Blanking time OUTB E2 OUTB D-GND Thermal shutdown circuit VBB1 OSC CR D-GND OUTA E1 OUTA Blanking time GND SUBGND IA2 IA1 ENABLE1 PHASE1 VREF1 Current selection circuit Control logic circuit ILB01559 No.7633-4/9 LB1945D Application circuit Motor L Motor L 1 OUTB OUTA 28 2 OUTB OUTA 27 3 NC 4 SUBGND 5 VBB 6 E2 7 D-GND NC 26 SUBGND 25 0.5Ω E1 24 0.5Ω 820pF 8 CR D-GND 23 24V VBB 22 LB1945D 47μF 5V VCC 21 10μF 56kΩ 9 PHASE2 PHASE1 20 10 ENABLE2 ENABLE1 19 11 IB2 IA2 18 12 IB1 IA1 17 13 VREF2 VREF1 16 14 S-GND GND 15 Logic input Logic input 10μF 5V ILB01556 No.7633-5/9 LB1945D Truth Table ENABLE PHASE OUTA Low High High OUTA Low Low Low Low High High - OFF OFF I1 I2 Output current Low Low Vref/(10 × RE) = IOUT High Low Vref/(15 × RE) = IOUT × 2/3 Low High Vref/(30 × RE) = IOUT × 1/3 High High 0 Note: The output is turned off when ENABLE is high or in the I1 = I2 = high state. Clockwise/counterclockwise Operating Sequence 2-phase excitation drive Clockwise rotation IA1 = IA2 = IB1 = IB2 = 0 No. PHASE1 OUTA OUTA PHASE2 OUTB OUTB 0 0 0 1 0 0 1 1 1 1 0 0 0 1 2 1 1 0 1 1 0 3 0 0 1 1 1 0 No. PHASE1 OUTA OUTA PHASE2 OUTB OUTB 0 0 0 1 1 1 0 1 1 1 0 1 1 0 2 1 1 0 0 0 1 3 0 0 1 0 0 1 Counterclockwise rotation IA1 = IA2 = IB1 = IB2 = 0 Control Sequence 2-phase excitation Table 1 ENABLE1 = ENABLE2 = 0 Phase A NO Phase B PH1 IA2 IA1 Current value PH2 IB2 IB1 Current value 0 0 0 0 1 0 0 0 1 1 1 0 0 1 0 0 0 1 2 1 0 0 1 1 0 0 1 3 0 0 0 1 1 0 0 1 1-2 phase excitation - 1/2 step Table 2 ENABLE1 = ENABLE2 = 0 Phase A No. Phase B PH1 IA2 IA1 Current value PH2 IB2 IB1 Current value 0 0 0 0 1 * 1 1 0 1 0 0 1 2/3 0 0 1 2/3 2 * 1 1 0 0 0 0 1 3 1 0 1 2/3 0 0 1 2/3 4 1 0 0 1 * 1 1 0 5 1 0 1 2/3 1 0 1 2/3 6 * 1 1 0 1 0 0 1 7 0 0 1 2/3 1 0 1 2/3 No.7633-6/9 LB1945D 1-2 phase Excitation Timing Chart PH1 IA2 IA1 PH2 IB2 IB1 IOUT1 VOUT1 0 1 2 3 4 5 6 7 IOUT2 VOUT2 1 cycle = T ILB01558 No.7633-7/9 LB1945D W1-2 phase excitation - about 1/4 step Table 3 ENABLE1 = ENABLE2 = 0 Phase A NO PH1 IA2 Phase B IA1 Current value PH2 IB2 IB1 Current value 0 0 0 0 1 * 1 1 0 1 0 0 0 1 0 1 0 1/3 2 0 0 1 2/3 0 0 1 2/3 3 0 1 0 1/3 0 0 0 1 4 * 1 1 0 0 0 0 1 5 1 1 0 1/3 0 0 0 1 6 1 0 1 2/3 0 0 1 2/3 7 1 0 0 1 0 1 0 1/3 8 1 0 0 1 * 1 1 0 9 1 0 0 1 1 1 0 1/3 10 1 0 1 2/3 1 0 1 2/3 11 1 1 0 1/3 1 0 0 1 12 * 1 1 0 1 0 0 1 13 0 1 0 1/3 1 0 0 1 14 0 0 1 2/3 1 0 1 2/3 15 0 0 0 1 1 1 0 1/3 W1-2 phase Excitation Timing Chart PH IA IA PH IB IB IOUT VOU 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 IOUT VOU 1 cycle = ILB01557 No.7633-8/9 LB1945D Simplified Equations for Determining RC Component Values The equations for setting the RC oscillator circuit rise time (T1) and fall time (T2) are shown below. T1 ≈ 0.44C × R (s) T2 ≈ 0.72 × ( C × R × 1000 )/( R + 1000 ) (s) (C:220 to 4700pF, R = 10 to 150kΩ) The oscillator frequency must be set using the simplified equations shown above. Note that the triangle wave fall time (T2) is also used as the noise canceller time. Motor CR T2 T1 T2 Usage Notes 1. VREF Since the VREF pin is the input pin for the reference voltage that sets the current, applications must be designed so that noise does not appear on this pin. 2. Ground pins Since this IC switches high currents, the following points concerning grounding must be observed. • The fins on the package rear surface, pins 7 and 8, and pins 21 and 22 must all be grounded. • Sections of the circuit that carry large currents must be implemented with wide lines in the printed circuit pattern, and must be physically separated from the small signal system. • The E pin sense resistor (RE) must be position as close as possible to the IC ground (pin 14). • The capacitors between VCC and ground and between VBB and ground must be positioned as close as possible to the VCC and VBB pins on the printed circuit pattern. ON Semiconductor and the ON logo are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of SCILLC’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PS No.7633-9/9