PROBLEM TO BE SOLVED: To provide an ultrasonic sensor allowing individual drive of transmission/reception elements in time of transmission, and allowing improvement of reception sensitivity.SOLUTION: This ultrasonic sensor 10 includes: a plurality of transmission/reception dual-use elements 310 first electrode side switches 71, 73 connected to first electrodes of the respective transmission/reception dual-use elements second electrode side switches 72, 74 connected to second electrodes of the respective transmission/reception dual-use elements a control circuit 60 a transmission circuit 40 a reception circuit 50 a common-electrode connection wiring line 80 and a serial connecting wiring line 81. When transmitting an ultrasonic signal, the control circuit 60 connects the switches 71, 73 to the transmission circuit 40, connects the switches 72, 74 to the common-electrode connection wiring line 80, and connects the respective transmission/reception dual-use elements 310 in parallel to the transmission circuit 40 and the common electrode connection wiring line 80. When receiving an ultrasonic signal, the control circuit 60 connects the switches 71, 73 and the switches 72, 74 to the serial connecting wiring line 81, and serially connects the respective transmission/reception dual-use elements 310 to the reception circuit 50.COPYRIGHT: (C)2012,JPO&INPIT【課題】送信時に送受信素子を個別に駆動でき、受信感度を向上できる超音波センサーを提供すること。【解決手段】超音波センサー10は、複数の送受信兼用素子310と、各送受信兼用素子の第1電極に接続された第1電極側スイッチ71,73と、各送受信兼用素子の第2電極に接続された第2電極側スイッチ72,74と、制御回路60と、送信回路40と、受信回路50と、共通電極接続配線80と、直列接続用配線81とを備える。制御回路60は、超音波信号の送信時は、スイッチ71,73を送信回路40に接続し、スイッチ72,74を共通電極接続配線80に接続し、各送受信兼用素子310を送信回路40および共通電極接続配線80に対して並列に接続する。制御回路60は、超音波信号の受信時は、スイッチ71,73およびスイッチ72,74を直列接続用配線81に接続し、各送受信兼用素子310を受信回路50に対して直列に接続する。【選択図】図3
