U642B
Pin Configuration
Pin
1
2
3
4
5
6
7
8
Symbol
GND
Function
GND
1
2
8
+V
Batt
Ground
Input 1 Interval switch
Timing capacitor C
RELAY
Input 1
t
c
7
6
2
R
4
Afterwiping time resistance
WIWA Wipe/Wash switch
Park switch for wiper motor
RELAY Relay control output
+V Supply voltage KI. 15
U642B
t
c
S
1
3
4
S
1
WIWA
R
4
5
Batt
93 7691
Figure 2. Pinning
Circuit Description
at the capacitor is greater than 6.5 V, the relay is turned
on as long as the switch ”WIWA” is closed.
Interval Function, Pin 2
By closing the internal switch, S , to supply voltage,
2
The after-wipe-time begins after the switch is open
whereas the sources D and F are switched OFF and the
source E is activated. Source E discharges the capacitor
till the voltage is less than 2.2 V. The relay is OFF and the
wiper-motor is switched OFF. The after-wipe-time is
determined by the current source E which can be
+V , the motor is activated. The internal current source
Batt
(Pin 3) which holds the capacitor C in charged state is
2
switched-OFF. As soon as there is a positive potential at
the park switch (S ), current source F (see figure 1)
1
charges the capacitor C very fast. After the wiper
2
operation is finished, S is again at ground potential, the
1
regulated with the external resistor R
. Afterwards the
Time
relay is in OFF position – interval pause begins – the
source A discharges the capacitor. Relay switch OFF is
capacitor C is discharged through the current source C,
2
independent of the park switch S .
till the voltage at Pin 3 is below the threshold of 2 V.
Interval pause can be adjusted between 4 s to 20 s with the
1
Interval and WIWA Functions
help of potentiometer R . Now the relay switches ON and
3
the next interval cycle begins. Opening switch S causes
The interval function is interrupted immediately when the
2
current source A to discharge C immediately and current
switch S is activated. The current source A discharges
2
2
sources C and F are switched-OFF.
the capacitor to a value of 2 V, afterwards the normal S
function starts.
2
Wipe/Wash (WIWA) Operation, Pin 5
Interval wiping starts immediately when the after-wipe-
time is over. The switching delays are slightly shorter,
because the capacitor is already charged to a value of 2 V.
By closing the WIWA-switch, S , to supply voltage,
3
+V , water pump starts spraying the water on the wind-
Batt
screen, the current source A is switched-OFF which keeps
the capacitor C in discharged state. Now the capacitor is The Wipe/Wash function is not interrupted when interval
2
charged through the current sources D and F, and when af- switch S is activated. Interval function begins after the
2
ter a time interval of approximately 100 ms, the voltage WIWA function is over.
2 (6)
TELEFUNKEN Semiconductors
Rev. A1, 13-Feb-97
TEMIC [ TEMIC SEMICONDUCTORS ]
