VEHICLE BLINK PULSE GENERATOR MANUFACTURABLE ON AN INTEGRATED CIRCUIT BASIS

An emitter-coupled differential amplifier has its inputs connected to the extremities of the diagonal of a bridge comprising resistors and a capacitor, while its output controls a Darlington circuit switch which when operated practically short-circuits the other diagonal of the bridge and causes the capacitor to charge and discharge between two limiting potentials and to make the differential amplifier operate as an astable multivibrator. The Darlington switch also controls the blinker relay. A stabilizing switching circuit controlled by the current flow through a series resistor in the lamp circuit is arranged normally to short-circuit, during the flash period of the lamps, one element of a voltage divider to which the bridge capacitor is connected so as to lengthen the multivibrator period, but if one lamp in the circuit has failed, this switching circuit will not operate, the voltage divider will not be short-circuited and the flash frequency will be increased, warning the driver of the vehicle by the usual pilot light. The circuit is designed for utilization of integrated circuit techniques.