U2640B telefunken semiconductors rev. a2, 02-dec-97 1 (10) intermittent- and wipe/wash control for wiper systems description with the u264xb, temic semiconductors developed a family of intermittent- and wipe/wash control circuits for windshield or backlite wiper systems with identical basic functions. the circuit design provides the possibility to generate ?x? versions using different metallization masks. thus, it is easy to verify a broad range of time se- quences which can be set independently of each other. features relay activation can be controlled by a limit switch of the wiper motor or by a fixed activation period for systems without limit switch debounced input stages enable/disable of pre-wash delay by program pin polarity of wiwa: v batt polarity of int: v batt relay output is protected with a clamping diode relay activation: 0.48 s interval pause: 5.8 s after wiping: 5.2 s pre-wash delay: 0.52 s wipe/wash mode with priority protected in accordance to iso/tr 7637?1 emc with intergrated filters ordering information extended type number package remarks U2640B dip8 U2640B?fp so8 block diagram 21 v 21 v 21 v 21 v input comparator voltage stabilization and por logic load- dump detection and output control oscillator 21 v open-collector relay driver v s osc int wiwa ls pp gnd rel 13944 figure 1. a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a1, 02-dec-97 2 (10) pin configuration pin symbol function 1 int intermittent input 2 wiwa wipe/wash (wiwa) input 3 ls limit switch (wiper motor) input 4 pp program pin 5 gnd ground 6 rel relay output 7 v s supply voltage 8 osc rc oscillator input osc v s gnd int wiwa pp ls 1 2 3 4 8 7 6 5 13365 rel figure 2. pinning functional description all times specified below refer to an oscillator frequency of 200 hz. figures 9 to 16 show the dependencies of the times upon battery voltage and temperature. the temperature dependence of the oscillator frequency is essentially determined by the temperature coefficient of the oscillator capacitor. the temperature dependence of the oscillator frequency can be reduced to minimum with a slightly negative temperature coefficient (n100). the capacitor used in figures 10 and 11 has a slightly positive temperatur coefficient. all times are permanently set and can be changed only jointly within certain limits by adjusting the oscillator frequency. see table 1. intermittent function the relay is energized for the time t on after the switch int is switched on with respect to v batt and after expira- tion of time t d (debounce). the debounce time ranges between 60 ms and 80 ms. a time period of 5 ms to 40 ms for internal sequence control must be added (asynchronism between operating instant and internal clock) e.g., the response time may range from 65 ms up to 120 ms. if the limit switch of the windscreen wiper motor is connected to pin ls , the relay is energized as long as the switch is at high potential, regardless of the relay on-time, t on , i.e., the motor current in interval mode flows via the relay contact only. in park position, the motor winding at both ends is connected to ground via the limit switch and the motor is decelerated immediately. the limit switch input is debounced with t dl = 17 ms. the relay on-time, t on , always elapses ? even if the interval switch was opened beforehand. interval pause the interval pause t int = 5.8 s follows t on . opening of switch int causes a debounce time, t d , and reclosing results in the relay on-time, t on , after t d . wipe/wash function without pre-wash delay (pp connected to gnd) the water pump is switched on when the switch wiwa is pressed and, after the debounce time, t d , the relay is energized. after-wiping time t aw = 5.2 s starts as soon as switch wiwa is opened and the debounce time, t d , has expired. if the limit switch is connected, the relay remains energized until the wiper arm returns to park position, i.e., the motor current flows via the relay contact only. wipe/wash function with pre-wash delay (pp connected to v s ) in wipe/wash mode, the relay is energized after a delay time. the water pump can spray water onto the wind- screen during the delay time, t del . the on-delay time of the U2640B is: t del = t d + 0.44 s = 0.52 s if switch wiwa is closed longer than t d but shorter than t del , the after-wiping time, t aw , starts after expiration of t del . the wipe/wash function with or without on-delay t del can be selected by programming pp. pp connected to gnd: without pre-wash delay pp connected to v s : with pre-wash delay the after-wiping time, t aw , is re-triggerable in both cases. intermittent and wipe/wash mode the wipe/wash function has priority over the interval function. if switch wiwa is closed during the interval a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a2, 02-dec-97 3 (10) function, wipe/wash mode is activated immediately after the debounce time, t d , even if an on-delay is programmed (t del = 0 s). expiry of t aw is directly followed by the next relay on-time, t on , of intermittent mode. oscillator all timing sequences are derived from an rc-oscillator whose charging time, t 1 , is determined by an external resistor, r osc, and whose discharging time, t 2, is determinated by an integrated 2-k resistor. since tolerance and temperature response of the integrated resistor are far higher than those of the external resistor, t 1 /t 2 must be selected to be greater than 20 for stability reasons. the minimum value of r osc should not be less than 68 k . calculating cycle duration and frequency: t = t 1 + t 2 = c osc ( 0.74 r osc + 2260 ) and f osc = 1/t calculating the capacitor for a given resistor: c osc = t / ( 0.74 r osc + 2260 ) calculating the oscillator resistance for a given capacitor: r osc = 1.34 ( t / c osc ? 2260 ) recommended frequency: f osc = 200 hz (for r osc = 200 k , c osc = 33 nf) all times can be varied jointly within specific limits by varying the oscillator frequency (see table 1). the oscilla- tor is operable up to 50 hz. power supply for reasons related to protection against interference and destruction, the pin v s must be provided with an rc net- work for limiting the current in the event of overvoltage and for buffering in the event of voltage drops. proposed ratings: r v = 510 , c v = 47 f. an integrated 14-v zener diode is connected between v s and gnd. interference voltages and load-dump in the case of transients, the integrated zener diode limits the voltage of the relay output to approximately 28 v. in the case of load-dump, a current (dependent upon r v and c v ) flows through the integrated 14-v zener diode, and the relay output is switched on at v batt > 30 v in order to avoid destruction of the output. the output transistor is rated such that it can withstand the current generated dur- ing the load-dump through the relay coil. in practice, the windscreen wiper motor is switched on via the relay and thus the amplitude of the load-dump pulse is limited. the supply voltage of the circuit is limited to 14 v by the inte- grated zener diode, and the inputs are protected by external protective resistors and integrated zener diodes. rf suppression is implemented with a low-pass filter at the inputs, consisting of a protective resistor and the inte- grated capacitor. power-on reset (por) when the supply voltage is applied, a power-on reset pulse is generated which sets the circuit?s logic to a defined initial state. the por threshold is approximately v s = 4.3 v. table 1. change in times by varying the oscillator frquency f osc (hz) t d [ ms ] t dl [ ms ] t on [ ms ] t int [ s ] t aw [ s ] t del [ s ] 100 140 35 960 11.84 10.24 920 120 116 29 800 9.68 8.53 766 140 100 25 686 8.45 7.31 657 160 87 22 600 7.40 6.40 575 180 77 19 533 6.57 5.68 511 200 70 17 480 5.92 5.12 460 220 64 16 436 5.38 4.65 418 240 58 14 400 4.93 4.26 383 260 54 13 370 4.55 3.94 353 280 50 12 343 4.23 3.66 328 300 46 11 320 3.95 3.41 306 400 35 9 240 2.96 2.56 230 a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a1, 02-dec-97 4 (10) absolute maximum ratings with recommended external circuitry parameter test conditions symbol value unit supply voltage (static) 5 min v batt 24 v supply current pulse 2 ms i s 1.5 a supply current pulse 300 ms i s 150 ma relay output current (static) i rel 300 ma relay output current pulse 300 ms i rel 1.5 a ambient temperature range t amb ?40 to +95 c storage temperature range t stg ?55 to +125 c power dissipation dip8 p tot 0.45 w power dissipation so8 p tot 0.34 w thermal resistance parameters symbol value unit junction ambient dip8 r thja 120 k/w junction ambient so8 r thja 160 k/w electrical characteristics reference point ground gnd, t amb = 25 c, v batt = 13.5 v, unless otherwise specified (see figures 11 and 12) parameters test conditions / pin symbol min typ max unit voltage supply pin 7 supply voltage v batt 6.0 16.0 v supply current i s 0.5 2.0 3.0 ma undervoltage threshold (por) v s 3.0 5.1 v internal z-diode v z 13.5 14.0 16.2 v internal capacitor c s 15 pf series resistance r v 510 filter capacitor c v 47 f oscillator input osc pin 8 internal discharge resistor r dis 1.3 2.0 3.2 k lower switching-point voltage v osc 0.16 v s 0.20 v s 0.24 v s v upper switching-point voltage v osc 0.55 v s 0.60 v s 0.65 v s v input current v osc = 0 v ?i osc 2 a oscillator frequency f osc 1 200 50 k hz input limit switch ls pin 3 internal protection-diode voltage i ls = 10 ma v ls 19.5 21.0 25.5 v internal capacitor c ls 25 pf switching threshold voltage v ls 0.375 v s 0.5 v s 0.675 v s v input current v ls = v s i ls 1 a internal pull-up resistor r ls 13 20 27 k external protection resistor r s 10 k a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a2, 02-dec-97 5 (10) unit max typ min symbol test conditions / pin parameters inputs int, wiwa and pp pins 1, 2 and 4 internal protection-diode voltage i e = 10 ma v e 19.5 21.0 25.5 v internal capacitor c e 25 pf switching threshold voltage v e 0.375 v s 0.5 v s 0.675 v s v input current v e = 0 v ?i e 1 a internal pull-down resistor r e 13 20 27 k external protection resistor r s 10 k relay output pin 6 saturation voltage i = 100 ma v rel 1.1 v saturation voltage i = 200 ma v rel 1.5 v z-diode clamp voltage i = 10 ma v rel 19.5 21.0 25.5 v leakage current v = 14 v i rel 12 a relay coil resistance r rel 60 load-dump protection threshold v batt 28 33 42 v internal pulse times debouncing period inputs int/wiwa 12 - 16 clocks t d 60 70 80 ms debouncing period inputs ls 3 ? 4 clocks t dl 15 17.5 20 ms relay activation time 96 clocks t on 480 ms intermittent pause t int 5.92 s after wiping period 1024 68 clocks t wiwa 4.78 5.46 s pre-wash delay, reaction time for switch-on delay = t del + t d 88 ? 96 clocks t del 440 480 ms note: all internally generated time sequences are derived from the oscillator frquency. the tolerances refer to a frequency adjusted to f osc = 200 hz. a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a1, 02-dec-97 6 (10) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 6 8 10 12 14 16 18 t ( s ) v batt (v) on figure 3. relay activation = f (v batt ) 0 1 2 3 4 5 6 7 8 9 10 6 8 10 12 14 16 18 t ( s ) v batt (v) int figure 4. interval pause = f (v batt ) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 6 8 10 12 14 16 18 t ( s ) v batt (v) del min max figure 5. pre-wash delay = f (v batt ) 0 1 2 3 4 5 6 7 8 9 10 6 8 10 12 14 16 18 t ( s ) v batt (v) aw min max figure 6. after-wipe time = f (v batt ) a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a2, 02-dec-97 7 (10) 0.2 0.3 0.4 0.5 0.6 0.7 0.8 ?40 ?20 0 20 40 60 80 100 t ( s ) temperature ( c ) on figure 7. relay activation = f (temperature) 0.2 0.3 0.4 0.5 0.6 0.7 0.8 ?40 ?20 0 20 40 60 80 100 t ( s ) temperature ( c ) del min max figure 8. pre-wash delay = f (temperature) 0 1 2 3 4 5 6 7 8 ?40 ?20 0 20 40 60 80 100 t ( s ) temperature ( c ) aw min max figure 9. after-wipe time = f (temperature) 0 1 2 3 4 5 6 7 8 ?40 ?20 0 20 40 60 80 100 t ( s ) temperature ( c ) int figure 10. interval pause = f (temperature) note: the temperature characteristic is caused by the temperature coefficient t c of the external capacitor a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a1, 02-dec-97 8 (10) application examples 8 7 65 123 4 U2640B r osc 200 k ? c osc 33 nf c v 47 f r v 510 ? r s 10 k ? r s 10 k ? m wiwa water? pump int m wiper? motor kl 15 13903 figure 11. application without limit switch 8 7 65 123 4 U2640B r osc 200 k ? c osc 33 nf c v 47 f r v 510 ? r s 10 k ? r s 10 k ? m wiwa water? pump int kl 15 13904 r s 10 k ? m wiper? motor end? switch figure 12. application with limit switch a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a2, 02-dec-97 9 (10) package information 13021 9.8 9.5 package dip8 dimensions in mm 1.64 1.44 4.8 max 0.5 min 3.3 0.58 0.48 7.62 2.54 6.4 max 0.36 max 9.8 8.2 7.77 7.47 85 14 technical drawings according to din specifications 13034 technical drawings according to din specifications package so8 dimensions in mm 5.00 4.85 0.4 1.27 3.81 1.4 0.25 0.10 5.2 4.8 3.7 3.8 6.15 5.85 0.2 85 85 a d r o n i c c o m p o n e n t s g m b h
U2640B telefunken semiconductors rev. a1, 02-dec-97 10 (10) ozone depleting substances policy statement it is the policy of temic telefunken microelectronic gmbh to 1. meet all present and future national and international statutory requirements. 2. regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. it is particular concern to control or eliminate releases of those substances into the atmosphere which are known as ozone depleting substances ( odss). the montreal protocol ( 1987) and its london amendments ( 1990) intend to severely restrict the use of odss and forbid their use within the next ten years. various national and international initiatives are pressing for an earlier ban on these substances. temic telefunken microelectronic gmbh semiconductor division has been able to use its policy of continuous improvements to eliminate the use of odss listed in the following documents. 1. annex a, b and list of transitional substances of the montreal protocol and the london amendments respectively 2 . class i and ii ozone depleting substances in the clean air act amendments of 1990 by the environmental protection agency ( epa ) in the usa 3. council decision 88/540/eec and 91/690/eec annex a, b and c ( transitional substances ) respectively. temic can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances. we reserve the right to make changes to improve technical design and may do so without further notice . parameters can vary in different applications. all operating parameters must be validated for each customer application by the customer. should the buyer use temic products for any unintended or unauthorized application, the buyer shall indemnify temic against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. temic telefunken microelectronic gmbh, p.o.b. 3535, d-74025 heilbronn, germany telephone: 49 ( 0 ) 7131 67 2831, fax number: 49 ( 0 ) 7131 67 2423 a d r o n i c c o m p o n e n t s g m b h
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