Circuit for operating distance sensor, especially ultrasonic sensor, for motor vehicles

摘要

The circuit has a transmitter unit and a receiver unit. Both units are connected to an evaluation unit. The receiver unit has a device for amplitude matching the signal received from the sensor (1-4). The amplitude matching device is a compressor/expander arrangement. The signal from the sensor is passed through a preamplifier to the amplitude matching device. A selective amplifier for noise suppression is connected after the preamplifier.