l9907n motor bridge for headlight adjustment full bridge output configuration with low saturation voltage less than 3.2v at output current 0.7a operating supply voltage range 7v to 18v. supply overvoltage up to 50v high positioning precision and high noise immunity due to transfer characteristics with neutral zone and stop range threshold fast stop through short-circuiting the motor motor stop status in case of open input condition supply overvoltage protection function for vs more than 18v, up to 50v input protection against tran- sients on the battery line and the reverse battery condition thermal overload protection esd protected according to mil883c description the l9907n is a monolithic integrated power comparator with full bridge output configuration, intended for driving dc motors in positioning sys- tems, optimized for headlight adjustment applica- tion and respecting the automotive electronics en- vironmental conditions. december 1996 - 1.2v v inc r pr pr l9907n i inc inc v inf i inf inf v s gnd out c out f m i m d95at189 = = reference bias protection functions = + = - + = = 1.2v = v s block diagram ordering number: L9907ND (so20l) so20l(12+4+4) 1/8
absolute maximum ratings symbol parameter value unit v sdc dc supply voltage 26 v v sp supply voltage pulse (t 400ms) 50 v i out_dc dc output current 0.4 a i out_p output current pulsed (100ms) 0.8 a i in dc input current 10 ma i in input current pulse (2ms) 40 ma t s storage shutdown junction temperature range (*) 150 c (*) recommended maximal t amb 105c thermal data symbol parameter so20l unit r th j-amb thermal resistance junction-ambient (1) 50 c/w r th j-pins thermal resistance junction-pins 15 c/w (1) with 6cm 2 on board heat sink area v s out c n.c. gnd gnd gnd gnd n.c. in c in f n.c. gnd gnd gnd gnd n.c. out f n.c. 1 3 2 4 5 6 7 8 9 18 17 16 15 14 12 13 11 19 10 20 pr n.c. d95at181 pin connection l9907n 2/8
electrical characteristics (7v < v s < 18v, C40 c < t j < 150 c; unless otherwise specified.) symbol parameter test condition min. typ. max. unit i q quiescent current i out = 0, (output open) |v din | < 20mv (stop) |v din | < 200mv (l or r) 7 6 9 7 ma ma -v n -, v n+ neutral zone threshold (2) 1.5 < v inc < v s -2v; v s = 12v r pr = r pr = 0 3 x v st 3 x v st 120 240 4 x vst 4 x v st mv mv -v st- ,v st+ stop range threshold 1.5 < vinc < v s -2v; v s = 12v r pr = r pr = 0 25 50 38 76 60 100 mv mv v incl control input low disable threshold t j = -40 to +25oc t j = >25oc 0.8 0.6 1.2 1.2 1.5 1.5 v v v inch v ch (3) control input high disable threshold (4) outputs = on with rinc = 0 w with r inc = 5k w with r inc = 10k w v s -2 v s -1.5 v s -1.4 v v v outputs = off with r inc = 0 w with r inc = 5k w with r inc = 10k w v s -0.8 v s -0.6 v s -0.4 v v v i in input bias current 1.5 < v inc < v s -2v; v s = 12v v din = 0; r pr = v din = 200mv; r pr = v din = 0; r pr = 0 v din = 200mv; r pr = 0 0.45 0.9 0.8 1.5 2.0 4.0 3.6 6.8 m a m a m a m a v osi output saturation voltage sink stage i out = 0.7a i out = 0.35a 1.1 0.8 1.4 1.1 v v v oso output saturation voltage source stage i out = 0.7a i out = 0.35a 1.2 0.9 2 1.5 v v (2) with a programming resistor r pr between the pr pin and gnd the n+ and n- thresholds can be adjusted from the nominal value (r pr = , pin pr open) up to two times the nominal value (r pr = 0, pin pr shorted to gnd). the formula defining v n+, v n- typical value as a function of r pr and v s is: Cv n - = v n + = ( 36mv + 0.017 v s ) 1 + r pr 9.5k w 1 + 2 r pr 9.5k w . for r pr = this formula reduced to: -v n+ (r pr = ) = v n+ (r pr = ) = 18mv + 0.0086 v s . for v s in v and r pr in k w these formulas result in mv (3) v ch is the control input voltage applied to the pin i nc through a serial resistor r inc (4) outputs = undefined for: v s -2v < v ch (r inc = 0 w ) < v s -0.8v v s -1.5v < v ch (r inc = 5k w ) < v s -0.6v v s -1.4v < v ch (r inc = 10k w ) < v s -0.4v v n- motor direction right d95at182 v h- v h+ v n+ motor direction left v inc -v inf neutralzone stop range v m =v outc -v outf figure 1: l9907n differential input to output transfer characteristics l9907n 3/8
functional description the l9907n is a power comparator with full- bridge push-pull outputs, intended for driving a dc motor in the headling adjustment system. the basic function of the device is shown in the input-output tranfer characteristic, fig. 1. for differential input voltage (v inc - v inf ) lower than the negative neutral zone threshold, v n- the output voltage is negative (corresponds to motor direction right), for increasing differential in- put voltage, this status changes to the zero output voltage (motor is actively braked), when the differ- ential input voltage exceeds the v st- stop range threshold. the output status remains in this condi- tion as long as the differential input voltage re- mains within the neutral zone. if the input voltage increases above the positive neutral zone threshold v n+ , the output voltage become positive (motor direction left). similar behaviour is obtained for decreasing the input voltage. the output status transitions are marked with the arrows showing the correspond- ing direction of the output status variation. the active braking mode is got with both outputs in "high" status the above described behaviour assures high po- sitioning precision, corresponding to the stop range and high noise immunity in the adjusted condition due to the neutral zone hysteresis thresholds . both the above described thresholds are defined referring to i nc , i nf pins. the error due to voltage drop over the input signal source resistances r inc , r inf is minimized with extremely low input bias currents i inc , i inf . the above mentioned resistors (r inc , r inf ) are necessary for the input current limitation during the transients on the v bat line. the input source resistors must be dimensioned so that in case of a line transient the input current in the input pin, clamped with the internal input protection diodes do not increase over the specified absolute maxi- mum value. v bat v s -2v 1.5v v f 0 1.5v v s -2v v bat v c d95at183a figure 2: control to feedback transfer characteristic for tracking regulation (v f = v c within the nominal v inc operating range): d1 d2 c s i q r c v inc r inf r inc r pr r cf pr l9907n i inc inc v inf i inf inf v s r f v c v f gnd out c out f m v m i m v bat d95at184 module figure 3: recommended application circuit diagram with l9907n for tracking regulation (v f = v c for 1.5v < v c < v s -2v): note: recommended value of r inc , r inf (equivalent input resistance to i nc and i nf ) is 5k w to 10k w . resistor r cf should assure that the differential input voltage |v inc - v inf | remains within the neutral zone, when the control signal wire become broken. when this condition is fulfiled the motor will not change its previous position. l9907n 4/8
an external resistor r cf is recommended be- tween the slider of the control and feedback po- tentiometer. this resistor assures that in the case of input con- trol or input feedback wire interruption the input differential voltage will be within the neutral zone and the motor position remains frozen. the circuit features an overvoltage disable func- tion referred to the supply voltage v s higher than 18v, both outputs are forced to tristate in this con- dition. the thermal overload function disables the out- puts (tristate) when the junction temperature in- creases above the thermal shutdown threshold temperature of min. 150c. for the start of a heavy loaded motor, if the motor current reaches the max. value it is necessary to respect the dynamical thermal resistance junction to ambient. the maximum output current is 0.8a. the maximum junction temperature in this phase should not increase above the thermal shutdown threshold. in case of output disable due to ther- mal overload the output remains disabled till the junction temperature decreases under the thermal enable threshold. this behaviour is assured with the thermal shutdown hysteresis threshold , which minimum value is 20c. figure 3, 5 and 7 show typical application dia- grams for headlight adjustment applications. to assure the safety of the circuits in the reverse bat- tery condition a reverse protection diode d 1 , is necessary. the input currents in this condition are limited by the resistors r inc and r inf . the transient protec- tion diode d 2 must assure that the maximum rat- ing for v s during the transients at v bat line will be limited to a value lower than absolute maximum v bat v s -2v 1.5v v f 0 1.5v v s -2v v bat v c d95at185a figure 4: control to feedback transfer characteristic for proportional regulation with extended v c operating range: d1 d2 c s i q r c v inc r inf r inc1 r pr r inc2 pr l9907n i inc inc v inf i inf inf v s r f v c v f gnd out c out f m v m i m v bat d95at186 module figure 5: recommended application circuit diagram with l9907n for proportional regulation with extended v c operating range. for ideal adjusted condition v f = r inc2 r inc1 + r inc2 v c : note: recommended value of r inc , r inf (equivalent input resistance to i nc and i nf ) is 5k w to 10k w . if the motor should not change its position, when the control signal wire become open, r inc1 and r inc2 should be rated so that v inc 0.4v in this condition. l9907n 5/8
rating for v s . the device features an output dis- able function in case of control input voltage over- drive. when the control input voltage increases above the high control input disable threshold v inc > v inch , typically v s -1.2v or decreases below the low control input disable threshold v inc > v inch , typically 1.2v, then both outputs will be forced to tristate. the potential of the i nc pin is clamped at the con- trol input high disable threshold potential with a series resistor of 5k w typ. to activate the high disable comparator an input current of 35 m a typ. is needed. to respect this behaviour in the appli- cation v cr is specified for different r inc. v bat v s -2v 1.5v v f 0 1.5v v s -2v v bat v c d95at187a allowed vc operating range figure 6: control to feedback transfer characteristic for proportional regulation with reduced v c operating range: d1 d2 c s i q r c v inc r inf1 r inc r pr r cf pr l9907n i inc inc v inf i inf inf v s r f v c v f gnd out c out f m v m i m v bat d95at188 module r inf2 figure 7: recommended application circuit diagram with l9907n for proportional regulation with reduced v c operating range. for ideal adjusted condition v f = r inf2 r inf2 + r inf2 v c : note: recommended value of r inc , r inf (equivalent input resistance to i nc and i nf ) is 5k w to 10k w . resistor r cf should assure that the differential input voltage |v inc - v inf | remains within the neutral zone, when the control signal wire become broken. when this condition is fulfilled the motor will not change its previous position. l9907n 6/8
so20 package mechanical data dim. mm inch min. typ. max. min. typ. max. a 2.65 0.104 a1 0.1 0.3 0.004 0.012 a2 2.45 0.096 b 0.35 0.49 0.014 0.019 b1 0.23 0.32 0.009 0.013 c 0.5 0.020 c1 45 (typ.) d 12.6 13.0 0.496 0.512 e 10 10.65 0.394 0.419 e 1.27 0.050 e3 11.43 0.450 f 7.4 7.6 0.291 0.299 l 0.5 1.27 0.020 0.050 m 0.75 0.030 s 8 (max.) l9907n 7/8
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. ? 1996 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. l9907n 8/8
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