Transceiver circuit for film bulk acoustic resonator (FBAR) transducers
View Patent ↗A piezoelectric transducer device includes a receive signal path, a transistor and a piezoelectric transducer connected to a first terminal of the transistor. The device also includes a switch connected to a second terminal of the transistor, wherein the switch is adapted to selectively connect the second terminal of the transistor to a transmit signal or to a bias voltage; an output connected to a third terminal of the transistor, and adapted to receive a signal from the transducer when the switch is connected to the bias voltage, wherein the switch is not in the receive signal.
1. A piezoelectric transducer device, comprising:
a receive signal path;
a transistor;
a piezoelectric transducer connected to a first terminal of the transistor;
a switch connected to a second terminal of the transistor, wherein the switch is adapted to selectively connect the second terminal of the transistor to a transmit signal or to a bias voltage; and
an output connected to a third terminal of the transistor, and adapted to receive a signal from the transducer when the switch is connected to the bias voltage, wherein the switch is not in the receive signal path.
2. A transducer device as claimed in claim 1 , wherein the transistor is a field effect transistor (FET), the first terminal is a source, the second terminal is a gate and the third terminal is a drain.
3. A transducer device as claimed in claim 2 , wherein the transistor is a metal oxide semiconductor field effect transistor (MOSFET).
4. A transducer device as claimed in claim 1 , wherein the transistor is a bipolar transistor.
5. A transducer device as claimed in claim 1 , wherein the switch is one of: an optocoupler; a field effect transistor; or an electromechanical switch.
6. A transducer device as claimed in claim 1 , wherein the piezoelectric transducer is a film bulk acoustic resonator (FBAR) transducer.
7. A sensor, comprising:
piezoelectric transducer device, comprising: a transistor; a piezoelectric transducer connected to a first terminal of the transistor; a switch connected to a second terminal of the transistor, wherein the switch is adapted to selectively connect the second terminal of the transistor to a transmit signal or to a bias voltage; and an output connected to a third terminal of the transistor, and adapted to receive a signal from the transducer when the switch is connected to the bias voltage.
8. A sensor as claimed in claim 7 , wherein the transistor is a field effect transistor (FET), the first terminal is a source, the second terminal is a gate and the third terminal is a drain.
9. A sensor as claimed in claim 8 , wherein the transistor is a metal oxide semiconductor field effect transistor (MOSFET).
10. A sensor as claimed in claim 7 , wherein the transistor is a bipolar transistor.
11. A sensor as claimed in claim 7 , wherein the switch is one of: an optocoupler; a field effect transistor; or an electromechanical switch.