U842B
V
Batt
<t
WASH
OUT
1
0V
t
V
1R
Batt
t
1
t
7
0V
wipe1
wipe2
wipe3
V
Batt
PARK
0V
ON
MOTOR
OFF
13304
Figure 9. Wash operation with park switch signal
After operating the WASH switch, the relay is activated figure 9). During the third cycle, the wiper motor is sup-
after the debounce time, t . As long as the switch is plied via the park switch because the relay driver is
1
pushed, water is sprayed on the windscreen by the wash switched off after the second cycle.
pump. When it is released, the dry wiping starts after 100
Wipe/ Wash Mode without Park Position Feedback
ms reverse debouncing (t ).
1R
If U842B is used without the wiper motor’s park switch,
Pin 3 stays at high potential via its integrated pull-up
Wipe/ Wash Mode with Park Position Feedback
If the park input of the circuit is connected to the park resistor. Therefore, the driver stage switches off after the
switch, the dry wiping lasts three full wipe cycles (see fixed dry wiping time t .
2
V
Batt
<t
WASH
OUT
1
0V
t
1R
V
Batt
t
t
1
2
0V
V
Batt
PARK
0V
ON
MOTOR
OFF
13305
Figure 10. Wash operation without park signal report
TELEFUNKEN Semiconductors
7 (12)
Rev. A2, 03-Feb-97
TEMIC [ TEMIC SEMICONDUCTORS ]
