Ultrasonic sensor and electronic device

摘要

The ultrasonic sensor includes: a plurality of transmission/reception dual-use elements, first electrode switches connected to the first electrodes of the transmission/reception dual-use elements; second electrode switches connected to the second electrodes of the transmission/reception dual-use elements; a control circuit; a transmitting circuit; a receiving circuit; a common-electrode connection wiring; and serial connection wiring. When an ultrasonic signal is to be transmitted, the control circuit connects the first electrode switches to the transmitting circuit, connects the second electrode switches to the common-electrode connection wiring so that the transmission/reception dual-use elements are connected in parallel to the transmitting circuit and the common electrode. When an ultrasonic signal is to be received, the control circuit connects the first electrode switches and the second electrode switches to the serial connection wiring so that the transmission/reception dual-use elements are serially connected to the receiving circuit.

主权项

1. An ultrasonic sensor comprising:
a plurality of transmission/reception dual-use elements configured and arranged to transmit and receive ultrasonic waves, each of the transmission/reception dual-use elements including a first electrode and a second electrode; a plurality of first electrode switches respectively connected to the first electrodes of the transmission/reception dual-use elements; a plurality of second electrode switches respectively connected to the second electrodes of the transmission/reception dual-use elements; a control circuit configured and arranged to control transmission and reception of the ultrasonic waves of the transmission/reception dual-use elements; a transmitting circuit configured and arranged to output signals for ultrasonic wave transmission to the transmission/reception dual-use elements; a receiving circuit configured and arranged to receive signals outputted from the transmission/reception dual-use elements when ultrasonic waves are received by the transmission/reception dual-use elements; a common-electrode connection wiring connected to a common electrode; and a serial connection wiring serially connecting the transmission/reception dual-use elements, wherein when an ultrasonic signal is to be transmitted, the control circuit is configured and arranged to connect the first electrode switches to the transmitting circuit, and to connect the second electrode switches to the common-electrode connection wiring so that the transmission/reception dual-use elements are connected in parallel to the transmitting circuit and the common electrode, and when an ultrasonic signal is to be received, the control circuit is configured and arranged to connect the first electrode switches and the second electrode switches to the serial connection wiring so that the transmission/reception dual-use elements are serially connected to the receiving circuit.