An ultrasonic detection circuit includes a transmitter circuit that provides excitation signals to an ultrasonic transducer during an excitation interval. A control circuit includes a port to receive a command. The control circuit controls the frequency and the duty cycle of the excitation signals of the transmitter circuit during the excitation interval. The control circuit generates a first excitation signal sequence of the excitation interval followed by a first monitoring period to receive a first echo signal in response to the command. The control circuit generates a second excitation signal sequence of the excitation interval followed by a second monitoring period to receive a second echo signal in response to the command. The control circuit outputs results via the port based on at least one of the first or second echo signals received.