HIGH-CURRENT PWM/ UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS

SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS SMA7029M 1 Data Sheet 28201 OUTA OFF DELAY A REFERENCE A GROUND A IN A OUT A SENSE A CNTRL SPLY SENSE B OUT B OFF DELAY B GROUND B REFERENCE B IN B OUT B VREF + The SLA7024M, SLA7026M, and SMA7029M are designed for high-efficiency and high-performance operation of 2-phase, unipolar stepper motors. An automated, innovative packaging technology combined with power FETs and monolithic logic/control circuitry advances power multi-chip modules (PMCMs™) toward the complete integration of motion control. Highly automated manufacturing techniques provide low-cost and exceptionally reliable PMCMs suitable for controlling and directly driving a broad range of 2-phase, unipolar stepper motors. The three stepper motor multi-chip modules differ primarily in output current ratings (1.5 A or 3.0 A) and package style. All three PMCMs are rated for an absolute maximum limit of 46 V and utilize advanced NMOS FETs for the high-current, high-voltage driver outputs. The avalanche-rated (≥100 V) FETs provide excellent ON resistance, improved body diodes, and very-fast switching. The multi-chip ratings and performance afford significant benefits and advantages for stepper drives when compared to the higher dissipation and slower switching speeds associated with bipolar transistors. Normally, heat sinks are not required for the SLA7024M or SMA7029M. The SLA7026M, in demanding, higher-current systems designs, necessitates suitable heat transfer methods for reliable operation. Complete applications information is given on the following pages. PWM current is regulated by appropriately choosing current-sensing resistors, a voltage reference, a voltage divider, and RC timing networks. The RC components limit the OFF interval and control current decay. Inputs are compatible with 5 V logic and microprocessors. CONTROL/LOGIC VREF ABSOLUTE MAXIMUM RATINGS at TA = +25°C Load Supply Voltage, VBB . . . . . . . . . . . . 46 V FET Output Voltage, VDS . . . . . . . . . . . 100 V Control Supply Voltage, VCC . . . . . . . . . . 46 V Peak Output Current, IOUTM (tw ≤ 100 µs) SLA7024M . . . . . . . . . . . . . . . . . . . . . 3.0 A SLA7026M . . . . . . . . . . . . . . . . . . . . . 5.0 A SMA7029M . . . . . . . . . . . . . . . . . . . . 3.0 A Continuous Output Current, IOUT SLA7024M . . . . . . . . . . . . . . . . . . . . . 1.5 A SLA7026M . . . . . . . . . . . . . . . . . . . . . 3.0 A SMA7029M . . . . . . . . . . . . . . . . . . . . 1.5 A Input Voltage Range, VIN . . . . -0.3 V to 7.0 V Reference Voltage, VREF . . . . . . . . . . . 2.0 V Package Power Dissipation, PD . See Graph Junction Temperature, TJ . . . . . . . . . +150°C Operating Temperature Range, TA . . . . . . . . . . . . . . . . . . . . -20°C to +85°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . -40°C to +150°C + 2 3 4 5 6 7 VCC 8 9 10 11 12 13 14 15 CONTROL/LOGIC Dwg. PK-007 BENEFITS AND FEATURES s s s s s s s s Cost-Effective, Multi-Chip Solution ‘Turn-Key’ Motion-Control Module Motor Operation to 3 A and 46 V 3rd Generation High-Voltage FETs 100 V, Avalanche-Rated NMOS Low r DS(on) NMOS Outputs Advanced, Improved Body Diodes Single-Supply Motor/Module Operation s s s s s s s s s s Half- or Full-Step Unipolar Drive High-Efficiency, High-Speed PWM Dual PWM Current Control (2-Phase) Programmable PWM Current Control Low Component Count PWM Drive Low Internal Power Dissipation Heat Sinking (Normally) Unnecessary Electrically Isolated Power Tab Logic IC- and µP-Compatible Inputs Machine-Insertable Package Always order by complete part number: Part Number SLA7024M SLA7026M SMA7029M ™ Package 18-Lead Power-Tab SIP 18-Lead Power-Tab SIP 15-Lead SIP Output Current 1.5 A 3.0 A 1.5 A SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS SLA7024M and SLA7026M FUNCTIONAL BLOCK DIAGRAM CONTROL SUPPLY 7 12 V CC IN 6 17 A/B IN A/B 5 16 OUT A/B OUT 1 11 A/B 8 18 REG. REFERENCE + 3 14 + 13 2 OFF-TIME DELAY 15 4 GROUND CHANNEL A PIN NUMBERS CHANNEL B PIN NUMBERS 10 9 SENSE Dwg. FK-005 Note that channels A and B are electrically isolated. SMA7029M FUNCTIONAL BLOCK DIAGRAM CONTROL SUPPLY 8 8 V CC IN A/B 5 14 OUT A/B 1 10 OUT A/B 6 15 REG. REFERENCE + 3 13 + 11 2 OFF-TIME DELAY 12 4 GROUND CHANNEL A PIN NUMBERS CHANNEL B PIN NUMBERS 9 7 SENSE Dwg. FK-005-1 Note that except for the control supply, channels A and B are electrically isolated. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1994 Allegro MicroSystems, Inc. ™ SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS ALLOWABLE PACKAGE POWER DISSIPATION ALLOWABLE PACKAGE POWER DISSIPATION in WATTS 25 SLA7024M and SLA7026M 20 PREFIX 'SLA' R θJM = 5.0°C/W 15 PREFIX 'SMA' RθJM = 6.0°C/W CONTROL/LOGIC CONTROL/LOGIC + VREF 5 PREFIX 'SLA' R θJA = 28°C/W PREFIX 'SMA' R θJA = 31°C/W 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 VCC VCC VREF 10 + REFERENCE B GROUND B SENSE B CNTRL SPLY B OFF DELAY B REFERENCE A OUT A OFF DELAY A GROUND A 0 25 50 75 100 TEMPERATURE in °C 125 150 Dwg. GK-018 CNTRL SPLY A SENSE A OUTA Dwg. PK-006 ELECTRICAL CHARACTERISTICS at TA = +25°C Limits Characteristic FET Leakage Current FET ON Voltage Symbol IDSS VDS(ON) Test Conditions VDS = 100 V, VCC = 44 V (SLA7024M & SMA7029M) VCC = 14 V, IOUT = 1 A (SLA7026M) VCC = 14 V, IOUT = 3 A FET ON Resistance (SLA7024M & SMA7029M) VCC = 14 V, IOUT = 1 A (SLA7026M) VCC = 14 V, IOUT = 3 A Body Diode Forward Voltage Control Supply Voltage Control Supply Current Input Current VCC ICC IIN(H) IIN(L) Input Voltage VIN(H) VIN(L) NOTE: Negative current is defined as coming out of (sourcing) the specified device pin. Min — — — — — — — 10 — — — 2.0 — Typ — — — — — 0.9 0.9 24 10 — — — — Max 4.0 600 850 600 285 1.5 1.6 44 15 40 -800 — 0.8 Units mA mV mV mΩ mΩ V V V mA µA µA V V rDS(on) VSD (SLA7024M & SMA7029M) IOUT = –1 A (SLA7026M) IOUT = –3 A Operating VCC = 44 V VCC = 44 V, VIN = 2.4 V VIN = 0.4 V OUT B OUTB IN B IN A IN A IN B SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS TYPICAL STEPPER MOTOR APPLICATIONS (Half of Each Device Shown) SLA7024M and SLA7026M V BB A IN B IN B A OUT B 12 V CC 17 16 18 11 OUT B REG. V b +5 V R 1 510 Ω TO CHANNEL A VREF 14 + + R 2 100 Ω 2.4 kΩ R 5 td 13 15 SENSE 10 +5 V 47 kΩ R3 470 pF C1 C 3 2200 pF R S ≤1 Ω Dwg. EK-008 TRUTH TABLES (Device Types as Designated) WAVE DRIVE (FULL STEP) for SLA7024M and SLA7026M Sequence Input A Input A Input B Input B Output ON 0 H L L L A 1 L L H L B 2 L H L L A 3 L L L H B 0 H L L L A 2-PHASE (FULL STEP) OPERATION for SLA7024M and SLA7026M Sequence Input A Input A Input B Input B Outputs ON 0 H L H L AB 1 L H H L AB 2 L H L H AB 3 H L L H AB 0 H L H L AB HALF-STEP OPERATION (2-1-2 SEQUENCE) for SLA7024M, SLA7026M, and SMA7029M Sequence Input A Input A or tdA* Input B Input B or tdB* Output(s) ON 0 H L L L A 1 H L H L AB 2 L L H L B 3 L H H L AB 4 L H L L A 5 L H L H AB 6 L L L H B 7 H L L H AB 0 H L L L A *Logic signals to external open-collector inverter connected to tdA and tdB. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 ™ SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS TYPICAL STEPPER MOTOR APPLICATIONS (Half of Device Shown) SMA7029M V BB A IN B A OUT B 8 V CC 14 10 15 OUT B REG. V b +5 V 510 Ω R 1 TO CHANNEL A VREF 13 + + R 2 100 Ω 2.4 kΩ R 5 td 11 12 SENSE 9 +5 V R 3 47 kΩ OPEN-COLLECTOR INVERTER C1 470 pF C 3 2200 pF R S ≤1 Ω Dwg. EK-008-1 TRUTH TABLES (SMA7029M Only) WAVE DRIVE (FULL STEP) for SMA7029M Sequence Input A Input tdA* Input B Input tdB* Output ON 0 H L L L A 1 L L H L B 2 L H L L A 3 L L L H B 0 H L L L A 2- PHASE (FULL STEP) OPERATION for SMA7029M Sequence Input A Input B Outputs ON 0 H L AB 1 H H AB 2 L H AB 3 L L AB 0 H L AB *Logic signals to external open-collector inverter connected to tdA and tdB. SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS APPLICATIONS INFORMATION REGULATING THE PWM OUTPUT CURRENT The output current (and motor coil current) waveform is illustrated in Figure 1. Setting the PWM current trip point requires various external components: Vb = Reference supply (typically 5 V) R1, R2 = Voltage-divider resistors in the reference supply circuit RS = Current sensing resistor(s) NOTE: The maximum allowable VREF input voltage is 2.0 V. The voltage-divider must be selected accordingly. Normal PWM (Full-Current/Running) Mode IOUT is set to meet the specified running current for the motor (Figure 2) and is determined by: IOUT ≈ VREF RS R2 R1 + R2 Vb RS I PHASE A OUT (1) or, if VREF is not known IOUT ≈ • (2) 0 PHASE A Dwg. WK-001 FIGURE 1. PHASE A COIL CURRENT WAVEFORM Vb VCC INPUT V BB B R1 R3 B R2 R5 C1 td A A V REF PEAK CURRENT DETECTOR PWM OFF-TIME CONTROL CONTROL LOGIC CURRENT CONTROL & RECIRCULATING CURRENT CONTROL SENSE C3 RS Dwg. EK-009 FIGURE 2. PWM CONTROL (RUN MODE) ™ 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 SLA7024M, SLA7026M, AND SMA7029M HIGH-CURRENT PWM, UNIPOLAR STEPPER MOTOR CONTROLLER/DRIVERS For given values of R1, R2, and V b (VREF ≈ 0.82 V), Figure 3 illustrates output current as a function of current-sensing resistance (RS). 3.0 SLA7026M MAX. OUTPUT TRIP CURRENT in AMPERES 2.5 R1 = 510 Ω R2 = 100 Ω RX = ∞ Vb = 5 V 1.5 2.0 1.0 SLA7024M & SMA7029M MAX. 0.5 0 0 0.5 1.0 1.5 2.0 2.5 3.0 CURRENT-SENSING RESISTANCE in OHMS 3.5 4.0 Dwg. GK-014 FIGURE 3. CURRENT-SENSING RESISTANCE Reduced/Holding Current Mode Additional circuitry (Figure 4) enables reducing motor curren