M54676P MITSUBISHI | Alldatasheet
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2-PHASE STEPPER MOTOR DRIVER M 54676P MITSUBISHI <CONTROL / DRIVER IC> 1KW 9KW DES CRIPT IO N The M54676P is a semiconductor IC to drive a bipolar stepper motor by the micro step method by changing the coil current of the motor continuously. FEAT URES l Highly-accurate micro step drive by chopping sink output transistor and source output transistor simultaneously l Bipolar and constant current drive l Built in a thermal shutdown circuit and standby circuits l Built in flywheel diodes APP LICAT IO N Office automation equipment such as printer and FAX FUNCT IO N The M54676P can drive a stepper motor by the 2-phase bipolar method and also controls the coil current. Furthermore, it controls the direction of the coil current by Ph input and the coil current value by Vref pin. Because two control circuits are built in this IC, a stepper motor can be driven with a single IC by the 2-phase bipolar method. B LOC K D IAGR A M PIN C O N FIG URAT IO N (TO P VIEW ) Outline 20P4 165 156 147 138 129 1110 M54676P OutA Out *A SG A Sense A GND GND Vref A Phase A Phase *A Vcc5 Phase *B PhaseB VrefB Sense B GND GND SG B Out *B OutB VM Internal bias TSD SenseA SenseB PhaseA Phase *A PhaseB GND SGB SGA OUT B OUT *B Vcc5 9KW 0.2V 1KW 0.2V Vref B Amp 20KW 6KW 4 8 56 11 12914 VM OUT A OUT *A VrefB VrefA Vref A Amp Vref 2 comparator 1 2713 20 1716 15 - + - + C urrent comparator - + - + - + C urrent com parator Vref2 com parator Phase *B
2-PHASE STEPPER MOTOR DRIVER M 54676P MITSUBISHI <CONTROL / DRIVER IC> Pins Pins Pins Pins Pins Pins Pin (Vcc5) voltage (Operating mode) Pin Pin Pins Pins Conditions 100mm x 100mm, t=1.6mm Glass epoxy board ( q ja=50˚C/W ) Ratings Vcc5 – 20 -0.3 – 7 500 -0.3 – 7 -0.3 – 7 2.5 20.0 150 0 – 75 -20 – 125 Symbol UnitParameter ABS O LUT E M AXIM UM RA TING S ( Ta= 25˚C, unless otherwise noted ) VM Vcc5 Iout Vanalg Vlogic Pt K q Tj Ta Tstg Supply voltage 1 V V mA V V W mW/˚C Limits Min. Typ. Max. Symbol Test conditions UnitParameter ELEC TR ICAL C HAR ACT ER ISTIC S ( DC CHA R ACT ER ISTIC S )( Ta=25˚C ,VM =12V,Vcc=5V,unless otherw ise noted ) 4.5 -200 Vcc off 1.35 5.0 -10 1.8 5.5 0.8 100 Vcc5 -1.5 V V V mA mA m A nA V Vsat Vcc5 H Vcc5 L Icc10 Icc20 Istby Ivref Vref Vsense Vcoff Vin H Vin L Iin H Iin L Isense Ioff 230 0.1 2.0 -20 -15 250 0.2 270 0.3 Vcc5 0.8 100 mV V V V m A m A m A m A Limits Min. Typ. Max. Symbol Test conditions Unit Parameter ELEC TR ICAL C HAR ACT ER ISTIC S AC C H AR AC TER ISTIC S Ta=25˚C ,VM =12V,Vcc=5V,unless otherw ise noted Tdon Output turn-on delay 0.3 1.0 m S Tdoff Tdamp Tdph Time required to turn on output when Sense pin voltage is decreased from 0.5V to 0V at Vref=2.5V Time required to turn off output when Sense pin voltage is increased from 0V to 0.5V at Vref=2.5V Time required to turn on output when Vref pin voltage is increased from 0V to 3.5V at Sense=0.25V Time required to turn on output when Phase pin voltage is increased from 0V to 5V at Vref=2.5V and Sense=0V 1.5 2.5 m S 10 30 m S Tdoff Tdon 31 2 m S Supply voltage 2 Maximum output current Analog input voltage Logic input voltage Allowable loss Thermal derating Junction temperature Operating temperature Storage temperature ditto Output saturation voltage Vcc5 input voltage H Vcc5 input voltage L Circuit current VM reactive current Standby VM current Vref input bias current Vref amplifier input voltage range Sense pin threshold voltage Comparator OFF reference voltage Logic input voltage H Logic input voltage L Logic input current H Logic input current L Sense input current Output cutoff current Load=350mA (total) Pin (Vcc5) voltage (Standby mode) Pin current (Vcc5=5V) Pin current (VM=12V, Vcc5=5V) Pin current (VM=12V, Vcc5=0V) See Vref-Vsense characteristics 12-4 Vcoff : Comparator OFF reference voltage Vref=0V Sense pin voltage when output changes at Vref=2.5V Output turn-off delay Vref amplifier response time Phase delay time and and and and and =5V =0V =0V and and
2-PHASE STEPPER MOTOR DRIVER M 54676P MITSUBISHI <CONTROL / DRIVER IC> FUNCT IO N DE SCRIPTIO N
- Phase input Phase input decides the output mode. *Z: High impedance In order to prevent through current caused by turning on output transistors simultaneously at PhaseA=Phase *A=“H”, both phase inputs go in the high mode simultaneously and output goes in the high impedance state. Furthermore, as a countermeasure against output through current at the time of phase switching, a delay time (3us) to turn on the motor drive output when phase input goes in high state is set within the IC.
- Vref input (Comparative voltage) Chopper current (motor current) is controlled by changing Vref input voltage. By inputting SIN wave to VrefA and COS wave to VrefB, A-phase coil current and B-phase coil current change continuously and the microstep drive of a stepper motor is performed.
- Current comparator Sense pin voltage (voltage fall at current sensing resistor = motor current) and Vref input proportional voltage (Vref/10) are compared. Sense pin voltage < Vref/10: the comparator output is in high state and outputtransistors are turned on. Then, current flows into the motor. Sense pin voltage > Vref/10: the comparator output is in low state and output transistors are turned off. Current does not flow into the motor. The above operation is repeated to control the current of the motor.
- Vref comparator Vref input proportional voltage {(Vref/10)} and internal reference voltage are compared. If Vref input voltage is 0.3V or lower, output transistors are turned off and motor current stops regardless of Phase input and Sense input.
- Standby circuit When Vcc5 voltage is 0.8V or below or open, the IC goes in the standby state. In the standby state, leak current does not flow into VM power supply, logic input pins (Phase input), and analog input pins (Vref input and Sense input). Never forget to set VM power supply to be the maximum voltage level among all voltages applied to the IC in the standby state. (As for details, refer to “PRECAUTIONS FOR USE.”)
- Thermal shutdown (TSD) circuit This IC has the thermal shutdown function to protect itself against damage by a fire when chip temperature rises abnormally.
- Flywheel diode Because flywheel diodes for chopper current control are built in this IC, it is not necessary to connect external flywheel diodes. Also, by connecting schottky diodes with low VF externally, it is possible to reduce thermal loss. PhaseA (PhaseB) HL LH HH LL H L L H Z Z Z Z Phase *A (Phase*B) OutA (OutB) Out *A (Out*B)
2-PHASE STEPPER MOTOR DRIVER M 54676P MITSUBISHI <CONTROL / DRIVER IC> APP LICAT IO N EXA M PLE Phase *BVCC5 OutB Out *B SGB SenseB VrefB PhaseB GND GND OutA Out *A SGA SenseA VrefA PhaseA Phase *A GND GND VM 12V f B f A 10 11 RS1 RS2 SC1 SC2 SR1 SR2 RS1,RS2 = 0.5W SR1,SR2 = 1.6KW SC1,SC2 = 0.1mF Stepper motor D/A input D/A input
2-PHASE STEPPER MOTOR DRIVER M 54676P MITSUBISHI <CONTROL / DRIVER IC> PRE CAUT IO N S FO R U SE Sequence of supply voltage (VM and Vcc5) and logic input volta g e The VM voltage should be the maximum voltage among all volt- ages applied to this IC. If no voltage is applied to VM and 5V voltage is applied to Vcc5 pin and logic input pin, leak current flows from Vcc5 pin and logic input pin to VM through a surge protection diode. Thermal shutdown function 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 excessive surge voltage applied externally by accident (or when the TSD function is damaged). Thermal loss In case that conditions for use (regarding supply voltage and output current) or a board used is changed, sufficient thermal evaluation should be conducted and design should be worked out to leave a margin for thermal loss. The higher the chopping frequency is, the larger switching loss within the IC becomes. Wirin g on the board Current is controlled by flowing output current to the current sensing resistor (1 ohmlevel) to measure the voltage fall. The output current performs the chopping operation at high speed. Therefore, wiring to flow current and to connect the high- impedance input pin (Vref) should be conducted carefully not to cause a cross talk. Se q uence After the VM voltage rises, set the Vcc5 power supply voltage and logic input voltage. Similarly, after Vcc5 supply voltage and logic input voltage rise, raise the VM supply voltage. VM Vcc5 and logic input Time (Open) VM 12V Mode Normal operation mode 12V Standby m ode (N o current flow s to logic inputpin and Vcc pin.) Leak current flows from Vcc5 pin and logic input pin to VM pin. Prohibited (Open) Vcc5 Logic input 5V,0V 5V,0V 5V,0V