HT642B
The HT642B is a bi-polar integrated circuit designed for the wiper application in the automotive market. It includes wipe, wash and internal mode.
FEATURES
Interval Pause: 4 to 20 s
After-wiping Time: 2 to 20 s
Wiper Motor's Park Switch
Wipe/Wash Mode Priority
One External Capacitor Determines All Time Sequences
Relay Driver with Z-diode
Load-dump Protected
Prewash Delay 300mS
Interference Protection According to VDE 0839 or ISO/TR 7637/1
FUNCTIONAL DESCRIPTION
As a convenience feature of the windshield wiper, intermittent and wipe/wash operation functions are implemented in most of the automobiles. The HT642B is a cost- effective solution for an accurate timing function control. Wipe/wash mode has priority over interval mode. Interval pause and after-wiping time can be set to fixed values by using resistors in a broad time range. Added value can be provided with an individual, continuous adjustment of the interval pause by a potentiometer which may be built into the stalk. For proper operation, it is mandatory to feed the signal of the wiper motor's park switch into HT642B.