MITSUBISHI <CONTROL / DRIVER IC> M54671SP 2-PHASE STEPPER MOTOR DRIVER DESCRIPTION PIN CONFIGURATION (TOP VIEW) The M54671SP is a semiconductor IC to drive a bipolar stepper motor directly by controlling the coil current with the constant current method. Standby input(1) St1 1 32 St2 Standby input(2) Comparator input(1) C1 2 31 C2 Comparator input(2) Comparator VR1 3 reference input(1) Bootstrap power Vbs1 4 supply(1) Output power VMM1 5 supply(1) FEATURES ● Wide output current control range (20 – 1200mA) ● Bipolar and constant current MA1 6 Current sensor(1) E1 7 M54671SP Output(1) ● Built in a thermal shutdown circuit Comparator reference input(2) Bootstrap power 29 Vbs2 supply(2) Output power 28 VMM2 supply(2) 30 VR2 8 APPLICATION 9 GND Office automation equipment such as printer, FDD, HDD, and FAX 10 Output(1) FUNCTION method and also control the coil current. Furthermore, it controls the direction of the coil current with Ph input pins (pins 16 and 17) One-shot-multi time constant(1) Output current direction switching(1) Because two control circuits are built in this IC, a stepping motor can be driven with a single IC by the 2-phase bipolar method. 26 E2 Current sensor(2) 24 GND 23 MB1 11 22 MB2 Output(2) Output power 21 VMM2 supply(2) 20 Vbs2 Power supply(1) Vcc1 14 and the coil current value with VR pins (pins 3 and 30). Output(2) 25 Output power supply(1) VMM1 12 Bootstrap power Vbs1 13 supply(1) The M54671SP can drive a stepper motor by the 2-phase bipolar 27 MA2 Bootstrap power supply(2) 19 Vcc2 Power supply(2) T1 15 18 T2 17 Ph2 Ph1 16 One-shot-multi time constant(2) Output current direction switching(2) Outline 32P4B St2 Standby input(2) VR2 Comparator reference input(2) Ph2 Output current direction switching(2) Vbs2 Bootstrap power supply(2) VMM2 Output power supply(2) MA 2 Output(2) MB 2 Output(2) VMM2 Output power supply(2) Vbs2 Bootstrap power supply(2) St1 Standby input(1) VR1 Comparator reference input(1) Ph1 Output current direction switching(1) Vbs1 Bootstrap power supply(1) VMM1 Output power supply(1) MA 1 Output(1) MB 1 Output(1) VMM1 Output power supply(1) Vbs1 Bootstrap power supply(1) 32 30 17 29 28 27 22 21 20 1 3 16 4 5 6 11 12 13 19 14 Voltage sensor Monostable Voltage sensor Standby circuit comparator 25 24 23 GND 31 C2 Comparator input(2) Monostable Standby circuit comparator 18 T2 26 E2 Current sensor(2) One-shot-multi time constant(2) 8 9 10 GND 2 C1 Comparator input(1) 15 T1 7 E1 Current sensor(1) One-shot-multi time constant(1) VCC1 Power supply(1) VCC2 Power supply(2) BLOCK DIAGRAM MITSUBISHI <CONTROL / DRIVER IC> M54671SP 2-PHASE STEPPER MOTOR DRIVER ABSOLUTE MAXIMUM RATINGS (Ta=25˚C, unless otherwise noted) Symbol VCC VMM Vbs VL VC VR IL IC IMM Pd Topr Tstg Parameter Conditions Supply voltage Output supply voltage Bootstrap supply voltage Logic input voltage Analog input voltage Comparative input voltage Logic input current Analog input current Output supply current Allowable loss Operating temperature Storage temperature Ratings Unit -0.3 – 7 -0.3 – 24 -0.3 – 27 -0.3 – 6 -0.3 – VCC -0.3 – 15 -10 -10 ±1500 1.70 -20 – 75 -55 – 125 V V V V V V mA mA mA W ˚C ˚C RECOMMENDED OPERATING CONDITIONS (Ta=25˚C, unless otherwise noted) Symbol VCC VMM Vbs IO tPLH tPHL TON Parameter Min. Limits Typ. 4.5 5 10 12 Vbs ≥ VMM+1V 800 20 Supply voltage Output supply voltage Bootstrap supply voltage Output current Logic input rise time Logic input fall time Thermal shutdown Max. 5.5 20 24 1200 2 2 160 Unit V V V mA µs µs ˚C ELECTRICAL CHARACTERISTICS (Ta=25˚C, unless otherwise noted) Symbol Parameter Test conditions VIH VIL VCH ICO IOFF Comparator threshold Comparator input current Output cutoff current VR=5V Vsat Saturation voltage Voltage at sensing resistor is not included. Vbs=12.7V, VMM=12V, IO=800mA tOFF td ICC IIH IIL Cutoff time Turn-off delay Supply current VMM=12V, tON ≥ 5µs dVK/dt ≥ 50mV/µs VCC=5V, 1phase VI=2.4V VI=0.4V Logic input voltage Logic input current “H” “L” “H” “L” VCC=5V Min. 2.0 0 420 -20 5 -0.4 Limits Typ. Max. Unit 450 VCC 0.8 480 20 100 V V mV µA µA 1.0 1.5 V 10 1.6 15 2.0 25 100 µs µs mA µA mA MITSUBISHI <CONTROL / DRIVER IC> M54671SP 2-PHASE STEPPER MOTOR DRIVER SWITCHING CHARACTERISTICS APPLICATION DESCRIPTION (1) PHASE INPUT Switching waveforms Phase input decides the output mode. VMA-VMB or VMB-VMA 1 TOFF = 0.69 x RT x CT MA H L PHASE H L MB L H (2) VR (Comparative voltage) TOFF TON 1/2 The current level can be continuously changed by changing the voltage at VR continuously. (3) Current sensor When the voltage fall at the current sensing resistor and the selected current level become of the same level, the VE VCH td comparator triggers monostable. Then the output stage is cut off for a certain time (TOFF). During this cutoff time, the current decreases slightly and falls short of the comparative level. After the cutoff time (TOFF), the output stage is in ON state again. This operation is repeated. (4) Single pulse generator At the comparator output rise edge, the monostable is triggered. The pulse width of the monostable at the external timing CT and RT is as follows. TOFF = 0.69 x CT x RT Retrigger during TOFF is neglected. TIMING CHART (5) Analog control The output current level can be continuously changed by 2-phase excitation changing the voltage at VR or the feedback voltage to the comparator. Phase 1 Phase 2 TYPICAL CHARACTERISTICS Thermal Allowable power dissipation (W) θj-c = 25°C/W 3 10cm2 aluminum heat sink (θc-a = 25°C/W) 2.5W 2 1.7W 1 Free air (θc-a = 48.5°C/W) 0 10 20 30 40 50 60 Ambient Temperature Ta (°C) 70 80 MITSUBISHI <CONTROL / DRIVER IC> M54671SP 2-PHASE STEPPER MOTOR DRIVER APPLICATION EXAMPLE (Stepping motor driver) VBS 13V VMM 12V 47µ F 1 St1 St2 32 2 C1 C2 31 3 VR1 VR2 30 4 Vbs1 Vbs2 29 5 VMM1 VMM2 28 6 MA1 MA2 27 7 E1 E2 26 CC1 CC2 RC1 RC2 9 GND M54671SP 8 RS1 25 RS2 GND 10 24 23 11 MB1 M B2 22 12 VMM1 VMM2 21 13 Vbs1 Vbs2 20 14 VCC1 VCC2 19 VCC 5V CT1 CT2 15 T1 T2 18 16 Ph1 Ph2 17 RT1 RT2 Phase 1 Phase 2 RS1, RC1, CC1, RT1, CT1, Stepper motor (3.7mH / 6Ω / phase) RS2 = 0.5Ω RC2 = 1kΩ CC2 = 820pF RT2 = 47kΩ CT2 = 330pF MITSUBISHI <CONTROL / DRIVER IC> M54671SP 2-PHASE STEPPER MOTOR DRIVER PRECAUTIONS FOR USE (1) Before use, never forget to short-circuit Vcc1 and Vcc2. (2) When the whole output current changes by a large margin (for example, when thermal shutdown operation causes intermittent flow of output current), the supply voltage may undergo a change. Therefore, selection and wiring of power supply should be conducted cautiously to avoid such a situation that the supply voltage exceeds the absolute maximum ratings. (3) When the supply voltage changes by a large margin, the operation of this IC may become unstable. In this case, the change of supply voltage can be controlled by connecting a capacitor between Vcc pin and GND pin. (4) Thermal shutdown function The state of thermal shutdown operation may differ according to the way of wiring within a board. Therefore, sufficient board evaluation should be conducted before use. When the board is changed, operation on the replacing board should be evaluated. The circuit board on which this IC is mounted is designed to realize low impedance between power supply and output pin. Therefore, it is desirable to take a safe measure such as fixing a fuse to avoid such a situation that the board is damaged by a fire when output pin is internally short-circuited by excessively applied surge voltage by accident. (5) Flywheel Flywheel diode is not built in this IC. Before use, connect a flywheel diode between each output (MA1, MB1, MA2, and MB2) and output power supply (VMM). (Refer to APPLICATION EXAMPLE.)