L6287 power combo driver description the f-vhs motor driver combo ic includes a double three phase brushless motor driver plus a dc full bridge motor driver for vcr application. the package is sdip42 (38+2+2 pin ground frame). the device is realized in bcd technology with power ldmos output stages. the gate drive for high side stages is provided by an internal charge pump with two external capaci- tors. the first three phase motor driver is devoted to the drum motor control. the phase sequence update signal is provided in- itially by an external start-up signal (fstart), whose frequency is internally divided by four, while, during normal operation, is provided by an optical tacho converter signal. this signal is used as clock and reset for the state machine. the regulation of the speed is externally provided by means of pwm signal generated by the m p (dpwm), without external sensing resistor. the feedback to the m p unit is given by a suitable open drain output signal (pud) synchronized by the internal state machine. the second three phase motor driver is devoted to the capstan control. while the drum will al- ways spin in a fixed direction, the capstan mo- tor needs a more sophisticated logic to control the changes in spin direction. the motor position detection is carried out by means of three comparators for hall effect sen- sors. the loop regulation for this motor is still pro- vided by the m p with the signals cpwm and cdir. the loading motor section include a full bridge dc motor driver. the motor operations are di- rectly set by the inputs lpwm, ldir according to the truth table reported on the page 5. the device also includes a circuit for early ther- mal alarm, last thermal alarm and thermal shut- down with hysteresys. the output of this stage is an open drain, kept on during normal operations. the therm signal follows the inverted fstart signal between early warning and last warning temperature, while remains in high impedance (off) after lastwarning temperature and during thermal shutdown. the standby state of the device is imposed by thermal shutdown undervoltage on vcc supply external signal fstart; this state is imposed automatically after a de- fined time-out. the time-out is realized by sensing the falling edges of the fstart signal: if no edges are re- corded for a time interval greater than a certain time constant, the standby condition is gener- ated. the time constant is defined by the external ca- pacitor cto. in the standby state the main functions (upper power stages, opto decoder, etc) of the device are turned off in order to minimize the power con- sumption. the device also implement a heater function. the heater transistor is off during thermal shutdown, undervoltage condition and during nor- mal working mode. the heater transistor is driven on when the external standby condition is present according to the following table: fstart high low heater off on during the on condition, the specified heater ron is not guaranteed if all the voltage supplies are not at their minimum nominal value. this is advanced information on a new product now in development or undergoing evaluation. details are subject to change withou t notice . february 1997 ordering number: L6287 sdip42 1/9
absolute maximum ratings symbol parameter value unit v dd drum supply voltage 20 v (**) v dc capstan supply voltage 20 v (**) v dl loading supply voltage 20 v (**) upper power v ds max motor output to ground voltage 20 v(***) lower power v ds max motor output to supply voltage 20 v (***) v cc logic supply voltage 7 v v s special supply voltage 7 v i p1 loading motor peak current (t on = 1 m s duty cycle = 2%) 1.6 a i pd drum motor peak current (t on = 1 m s duty cycle = 2%) 1.4 a i pc capstan motor peak current (t on = 1 m s duty cycle = 2%) 1.8 a v il logic input low state voltage -0.1 v v ih logic input high statevoltage 7 v v therm open drain maximum voltage 7 v v heat open drain maximum voltage 20 v (**) (**) not operative - standby condition (***) each motor driver pins connection thermal data symbol parameter value unit r thj-amb thermal resistance junction to ambient 48 c/w r th j-pins thermal resistance junction to pin 15 c/w note: batwing pin. L6287 2/9
block diagram cp1 = 0.01 m f cp2 = 0.1 m f L6287 3/9
pin description voltage supplies (the power supply voltage v dd , v dc , v dl must be connected toghether externally) v dd power supply voltage for drump motor v dc power supply voltage for capstan motor v dl power supply voltage for loading motor and charge pump v cc logic voltage supply l gnd logic ground gnd r capstan + drum power ground gnd l loading + charge pump power ground v s analog voltage supply s gnd analog ground note: the v cc and v s power supply must be together either at maximum or minimum value. drum motor d out u winding output u d out v winding output v d out w winding output w d pwm pwm logic pulse input. control signal generated by m p for dump motor current regulation. p ud logic output position feedback generated by the translator logic od optocoupler diode output oc external capacitor for tacho-converter integrator ot input for optocoupler transistor or tacho-converter external resistor. this resistor defines the full-light current level of the tacho. capstan motor c out u winding output u c out v winding output v c out w winding output w c pwm pwm logic pulse input. control signal generated by m p for current regulation. c dir motor direction logic input signal h1+ hall sensor differential input h1- h2+ hall sensor differential input h2- h3+ hall sensor differential input h3- loading motor l out a winding output a l out b winding output b l pwm pwm logic input. l dir direction logic input services heater open drain output for heater resistor v cp charge pump storage capacitor pin cp1 bootstrap capacitor pin cp2 bootstrap capacitor pin therm open drain thermal alarm output f start start-up logic signal for drum motor cto time out capacitor output L6287 4/9
electrical characteristics (tj = 0 to125 c; v cc = v s = 5v 5%; v dc = v dl = v dd = 10 to 18v; unless otherwise specified.) power supply symbol parameter test condition min. typ. max. unit (#)v dd drum power supply voltage 10 18 v (#)v dc capstan power supply voltage 10 18 v (#)v dl loading power supply voltage 10 18 v v cc logic power supply voltage 4.5 5.5 v v s sensor power supply voltage 4.75 5.25 v v ccth undervoltage threshold 3.6 4.4 v # warning the functionality of the i.c. is guaranted in this voltage range. nevertheless the specified operating voltages (v dc , v dd , v dl ), must be selected according to the load characteristics. proper cautions must be taken in the application in order to assure that the drain-sourc e voltage across each output power transistor does not exceed 20v max. loading motor activation truth table input output lpwm ldir louta loutb 00lowlow 01lowlow 1 0 high low 1 1 low high symbol parameter test condition min. typ. max. unit r dsh high side r dsonh 2 w r dsl low side rdsonl 2 w (*)i ol dc output current 800 ma (*)i pl peak output current duty cycle = 10%; t on = 500ms 1a drum motor symbol parameter test condition min. typ. max. unit i cd dc output current 400 ma (*)i cdp peak output current 600 ma (*)i pdb peak output current duty cycle = 10%; t on = 500ms 800 ma r dsh high side rdsonh 1.6 w r dsl low side rdsonl 1.6 w capstan motor symbol parameter test condition min. typ. max. unit i co dc output current 800 ma (*)i cop peak output current 1 a (*)i pob peak output current duty cycle = 10%; t on = 1ms 1.5 a r dsh high side rdsonh 1 w r dsl low side rdsonl 1 w (*) warning these current values are compatible with the structure of the ic power structure. nevertheless the use of these current levels could produce junction temperatures that force ic outside of the operative range due to the thermal characteristics of the choosen package. L6287 5/9
electrical characteristics (continued) drum tacho converter symbol parameter test condition min. typ. max. unit i od open loop output current v od = 1v; i oc = 100 m a (note 1) 30 60 ma i ot full light current range 0.5 3 ma i oc sink current v or = 0; i od = 0 0.2 0.5 m a i ot vs i or mismatch 5 10 % v ref opto resistor reference voltage v s = 4.75v 3.36 3.72 v v s = 5v 3.54 3.91 v v s = 5.25v 3.72 4.11 v v oc open loop opto capacitor voltage v od = 1v see fig. 1 v s = 4.75v v s = 5v v s = 5.25v 2.75 v v thr1 clock threshold voltage v s = 4.75v 2.19 2.42 v v s = 5v 2.30 2.54 v v s = 5.25v 2.42 2.67 v v thr2 reset threshold voltage v s = 4.75v 0.30 0.33 v v s = 5v 0.32 0.35 v v s = 5.25v 0.33 0.37 v t pud m p syncro pulse duration 1 3 m s i pud1 open drain sink current v o = 0.4v 5 ma note 1: the suggested c opt external capacitor value is 5 m f ( 5%) hall comparator symbol parameter test condition min. typ. max. unit v in input voltage range 0.5 2.7 v i b input bias current 1 m a v of input offset voltage 8 mv v hy switchable hysteresys vref = 1.5v; 10 40 mv thermal protection symbol parameter test condition min. typ. max. unit i therm open drain sink current v out = 0.4v (see note 1) 5 ma t s shutdown temperature 155 170 185 o c t sdh shutdown hysteresis 60 o c t al1 early warning temperature ts -40 o c t al2 last warning temperature (see note 2) ts -20 c note 1: therm output stage is on in the normal temperature range note 2: in the tal-tll temperature range therm signal follows the inverted fstart signal. after tll temperature this output is always in high impedance. if thermal shutdown is reached this pin will remain in this state until the shutdown hysteresys will be recovered. heater symbol parameter test condition min. typ. max. unit r dsheat heater r dson 3 ohm v heat heater voltage 18 v L6287 6/9
electrical characteristics (continued.) logic levels for digital inputs ( c pwm , c dir , d pwm , f start , l pwm , l dir ) a pull up resistor r i is connected between the c dir , f start , l pwm , l dir inputs pads; c pwm and d pwm are left unconnected. symbol parameter test condition min. typ. max. unit v il input low voltage 0.8 v v ih input high voltage 2 v r i pull up resistor 3.5 10.5 kohm time out stage symbol parameter test condition min. typ. max. unit i cto time out output current (note 1) 5 20 ua note 1: the suggested external capacitor value is c to = 1 m f ( 20% max) for f start = 20khz. figure 1: optocircuit open loop oc voltage. L6287 7/9
a1 b e b1 d 22 21 42 1 la e1 a2 c e1 e e2 gage plane .015 0,38 e2 e3 e sdip42 sdip42 package mechanical data dim. mm inch min. typ. max. min. typ. max. a 5.08 0.20 a1 0.51 0.020 a2 3.05 3.81 4.57 0.120 0.150 0.180 b 0.38 0.46 0.56 0.0149 0.0181 0.0220 b1 0.89 1.02 1.14 0.035 0.040 0.045 c 0.23 0.25 0.38 0.0090 0.0098 0.0150 d 36.58 36.83 37.08 1.440 1.450 1.460 e 15.24 16.00 0.60 0.629 e1 12.70 13.72 14.48 0.50 0.540 0.570 e 1.778 0.070 e1 15.24 0.60 e2 18.54 0.730 e3 1.52 0.060 l 2.54 3.30 3.56 0.10 0.130 0.140 L6287 8/9
information furnished is believed to be accurate and reliable. however, sgs-thomson microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result f rom its use. no license is granted by implication or otherwise under any patent or patent rights of sgs-thomson microelectronics. specification mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously s upplied. sgs-thomson microelectronics products are not authorized for use as critical components in life support devices or systems with out express written approval of sgs-thomson microelectronics. ? 1997 sgs-thomson microelectronics C printed in italy C all rights reserved sgs-thomson microelectronics group of companies australia - brazil - canada - china - france - germany - hong kong - italy - japan - korea - malaysia - malta - morocco - the n etherlands - singapore - spain - sweden - switzerland - taiwan - thailand - united kingdom - u.s.a. L6287 9/9
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