NJM2673 -1- stepper motor driver general description the NJM2673 is a stepper motor driver, which consists of a ls-ttl compartible logic input stage, off time control circuits and a pair of high power h-bridges and protection diodes. the output current is up to 1000ma. the NJM2673 with small number of external components conforms a complete control and drive unit for stepper moto r systems. . package outline NJM2673e3 features ? switched mode bipolar constant current drive ? wide voltage range 4 to 45v ? wide range of current control 5 to 1000ma ? half- step and full-step operation ? thermal overload protection ? package emp24 pin connection c2 5 6 7 8 9 10 11 12 20 19 18 17 16 15 14 13 njm 2673e3 24 23 22 1 2 3 4 21 vc c t1 vr1 i 11 gnd gnd e2 mb1 i 01 vmm phase2 i 02 t2 gnd gnd ma1 mb2 vr2 e2 phase1 c1 i 12 ma2 c2
NJM2673 - 2 - block diagram l og i c l og i c ma1 mb1 vmm1 vmm2 mb2 ma2 phase1 vcc gnd e2 e1 t s d current select ph ase 1 v cc current select i 0 1 i11 vr1 phase1 ph ase 2 i 0 2 i12 vr2 t1 t2 c2 c1
NJM2673 - 3 - pin description emp symbol description 1 2 3 4 5 6,7,18,19 8 9 10 11 12 13 14 15 16 17 20 21 22 23 24 v cc t 1 v r1 phase1 i 11 gnd i 01 m b1 c 1 e 1 v mm m a1 m a2 e 2 c 2 m b2 i 02 i 12 phase2 v r2 t 2 logic voltage supply normally +5v. clock oscillator, channel 1. timing pin connect a 56k ? resistance and a 820pf in parallel between t and ground. reference voltage, channel 1. controls the threshold voltage for the comparator and hence the output current. controls the direction of the motor current of m a1 and m b1 outputs. motor current flows from m a1 to m b1 when phase1 is high. logic input, channel 1. it controls, together with the i 01 input, the current level in the output stage. ground and negative supply. these pins are used for heat sinking. make sure that all ground pins are soldered onto a suitable large copper ground plane for efficient heat sinking. logic input, channel 1. it controls, together with the i 11 input, the current level in the output stage. motor output b, channel 2. motor current flows from m a1 to m b1 when phase1 is high. comparator input, channel 1. this input senses the instantaneous voltage across the sensing resistor, filtered through a rc network. common emitter, channel 1. connect the sense resistor between this pin and ground. motor supply voltage, 4 to 40v. motor output a, channel 1. motor current flows from m a1 to m b1 when phase1 is high. motor output a, channel 2. motor current flows from m a2 to m b2 when phase2 is high. common emitter, channel 2. connect the sense resistor between this pin and ground. comparator input, channel 2. this input senses the instantaneous voltage across the sensing resistor, filtered through a rc network. motor output b, channel 2. motor current flows from m a2 to m b2 when phase2 is high. logic input, channel 2. it controls, together with the i 12 input, the current level in the output stage. logic input, channel 2. it controls, together with the i 02 input, the current level in the output stage. controls the direction of the motor current of m a2 and m b2 outputs. motor current flows from m a2 to m b2 when phase2 is high. reference voltage, channel 2. controls the threshold voltage for the comparator and hence the output current. clock oscillator, channel 2. timing pin connect a 56k ? resistance and a 820pf in parallel between t and ground.
NJM2673 - 4 - absolute maximum retings (ta=25c ? ) parameter symbol min. max. unit voltage logic supply v cc 0 7 v motor supply v mm 0 45 v logic input voltage v i -0.3 v cc v comparator input voltage v c -0.3 v cc v reference input voltage v c -0.3 v cc v current motor output current i m -1000 +1000 ma logic input current i i -10 - ma analog input current i a -10 - ma temperature operating temperature t opr -40 85 c storage temperature t stg -55 150 c recommended operating conditions parameter symbol min. typ. max. unit logic supply v cc 4.75 5.00 5.25 v motor supply v mm 4 - 40 v motor output current i m -800 - 800 ma operating junction temperature tj -20 - +125 c rise time logic inputs t r - - 2 s fall time logic inputs t f - - 2 s
NJM2673 - 5 - erectrical characteristics (t j =+25 c, v cc =5v,v mm =40v,c t =820pf,r t =56k ? ) parameter symbol condition min. typ. max. unit general supply current i cc - - 60 ma turn off td dvc/dt 50mv/ s - 0.9 - s thermal shutdown temperature tsd - 170 - c logic input h level input voltage v ih 2.0 - - v l level input voltage v il - - 0.8 v h level input current i ih v i =2.4v - - 20 a l level input current i il v i =0.4v -250 - - a input resistance input resistance r r - 8.8 - k ? analog input threshold voltgae v ch v cm v cl v r =5.0v,i 0 =i 1 =l v r =5.0v,i 0 =h,i 1 =l v r =5.0v,i 0 =l,i 1 =h 405 284 134 450 315 150 495 347 163 mv mv mv input current i c -20 - - a motor output lower transistor saturation voltage v ol i m =500ma i m =800ma - - 1.1 1.3 1.4 1.7 v v upper transistor saturation voltage v ou i m =500ma i m =800ma - - 1.1 1.3 1.4 1.7 v v lower diode forward voltage drop v fl i m =500ma i m =800ma - - 1.0 1.2 1.3 1.6 v v upper diode forward voltage drop v fu i m =500ma i m =800ma - - 1.1 1.3 1.4 1.7 v v output leak current i il i 0 =i 1 =h - - 100 a monostable cut off time t off - 31 - s thermal characteristics parameter symbol condition min. typ. max. unit rth j-gnd - 13 - c thermal resistance rth j-a note2 - 42 - c notes 1. all voltages are with respect to ground. currents are positive into, negative out of specified terminal. 2. all ground pins soldered onto 20cm 2 pcb copper area with free air condition, t a =25 c. [caution] the specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. the application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights.
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