semiconductor group 1 tca 305 tca 355 tca 305 tca 355 bipolar ic features l lower open-loop current consumption; i s < 1 ma l lower output saturation voltage l the temperature dependence of the switching distance is lower and compensation of the resonant circuit tc (temperature coefficient) is easier l the sensitivity is higher, so that larger switching distances are possible and coils of a lower quality can be used l the switching hysteresis remains constant as regards temperature, supply voltage and switching distance l the tca 305 even functions without external integrating capacitor. with an external capacitor (or with rc combination) good noise immunity can be achieved l the outputs are temporarily short-circuit proof (approx. 10 s to 1 min depending on package) l the outputs are disabled when v s < approx. 4.5 v and are enabled when the oscillator stabilizes (from v s min = 5 v) l higher switching frequencies can be obtained l miniature package proximity switch p-dso-8-1 p-dip-14-1 p-dso-14-1 type ordering code tca 305 a q67000-a2291 package p-dip-14-1 tca 305 g q67000-a2305 p-dso-14-1 (smd) tca 355 g q67000-a2444 p-dso-8-1 (smd) n n not for new design 01.96
semiconductor group 2 tca 305 tca 355 tca 305 a tca 305 g the devices tca 305 and tca 355 contain all the functions necessary to design inductive proximity switches. by approaching a standard metal plate to the coil, the resonant circuit is damped and the outputs are switched. operation schematic: see tca 205 the types tca 305 and tca 355 have been developed from the type tca 205 and are out- standing for the following characteristics: logic functions oscillator outputs q not damped damped h l l h tca 355 g pin configurations (top view)
semiconductor group 3 tca 305 tca 355 block diagram standard turn-on delay referred to t a = 25 ?c
semiconductor group 4 tca 305 tca 355 absolute maximum ratings operating range characteristics v s = 12 v, t a = C 25 to 85 ?c parameter symbol unit limit values supply voltage output voltage v s v q 35 35 output current i q ma 50 v v junction temperature storage temperature range t j t stg 150 C 55 to 125 ?c ?c thermal resistance system - air tca 305 a tca 305 g r th sa r th sa 85 (135) 2) 140 (200) 2) k/w k/w distance, hysteresis resistance r di , r hy w 0 capacitances c i , c d m f 5 supply voltage v s v 5 to 30 3) oscillator frequency f osc mhz 0.015 to 1.5 ambient temperature t a ?c C 25 to 85 parameter typ. min. max. unit test condition limit values symbol open-loop current consumption 0.6 0.9 (1.0) 2) ma outputs open i s reference voltage 1) l-output voltage per output 3.2 0.04 0.10 0.22 0.15 0.35 0.75 v v v v i ref < 10 m a i q l = 5 ma i q l = 25 ma i q l = 50 ma v ref v q l v q l v q l h-output current per output 10 m a v q h = 30 v i q h threshold at 3 hysteresis at 3 2.1 0.5 0.4 0.6 v v v s 3 v hy turn-on delay 1) 600 C 25 % C 25 % ms/ m f t a = 25 ?c t d on switching frequency w/o c i 5 khz f s 1) tca 305 only 2) values in parenthesis apply to tca 355 only 3) operation at voltages less than 5 v (between approx. 2.5 and 5 v) is possible, if v ref is connected to v s . in this case v ref is no longer internally stabilized. additionally, the pin "turn-on delay" is to be applied as follows: if no turn-on delay is needed, this pin has to be connected to v s . if, however, a turn-on delay is required, the charge current for d d has to be adjusted with an external resistor between this pin and v s (recommended value 390 k ). w
semiconductor group 5 tca 305 tca 355 schematic circuit diagram oscilator turn-on delay for tca 305 a; g integrating capacitor outputs
semiconductor group 6 tca 305 tca 355 application circuit
semiconductor group 7 tca 305 tca 355 l 0 , c 0 resonant circuit r hy hysteresis adjustment r di distance adjustment d temperature compensation of the resonant circuit; possibly with series resistance for the purpose of adjustment. the diode is not absolutely necessary. whether it is used or not depends on the temperature coefficient of the resonant circuit. r i ; c i integration element. at pin 3 (integrating capacitance) we recommend a capacitor of typ. 1 nf. to increase noise immunity this capacitor can be substituted by an rc circuit with, e.g., r i = 1 m and c i = 10 nf. c d delay capacitor dimensioning examples in accordance with cenelec standard (flush) w m 12 m 18 m 30 ferrite pot core number of turns cross section of wire l 0 c 0 (styroflex ? ) f osc sn r a (metal) c d m 33 (7.35 3.6) mm 100 0.1 cul 206 m h 1000 pf appr. 350 khz 4 mm 8.2 k + 330 100 nf w w n 22 (14.4 7.5) mm 80 20 0.05 268 m h 1.2 nf appr. 280 khz 8 mm 33 k 100 nf w n 22 (25 8.9) mm 100 10 0.1 585 m h 3.3 nf appr. 115 khz 15 mm 22 k + 2.7 k 100 nf w w
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