Amplifier device and preamplifier

Abstract

An amplifier device and a preamplifier are proposed. The preamplifier includes a differential pair circuit, a load circuit, a first switching circuit, a current source circuit, and a second switching circuit. The differential pair circuit receives a first signal and a second signal. The load circuit is coupled between a first power supply terminal and a first output terminal and a second output terminal of the preamplifier. The first switching circuit is connected in series with the load circuit and coupled between the differential pair circuit and the first power supply terminal. The current source circuit is coupled between the differential pair circuit and the second power supply terminal to extract the first current and the second current from the differential pair circuit. The second switching circuit is coupled between the first output terminal, the second output terminal, and a reference voltage terminal.

Claims

1. A preamplifier, comprising: A differential pair circuit receives a first signal and a second signal that are differential signals to each other; A load circuit is coupled between a first power supply terminal and a first output terminal and a second output terminal of the preamplifier; a first switching circuit is connected in series with the load circuit and coupled between the differential pair circuit and the first power supply terminal; a current source circuit is coupled between the differential pair circuit and a second power supply terminal for extracting a first current and a second current from the differential pair circuit. A second switching circuit is coupled between the first output terminal, the second output terminal and a reference voltage terminal; And a third switching circuit, coupled between the differential pair circuit and the current source circuit.

2. The preamplifier as claimed in claim 1, wherein during a calibration phase, the first switching circuit disconnects the path of the differential pair circuit coupled to the first power supply terminal, and the first current and the second current sampled by the current source circuit are 0 amperes.

3. The preamplifier as claimed in claim 2, wherein during the correction phase, the second switching circuit is turned on, coupling the first output terminal and the second output terminal to the reference voltage terminal.

4. The preamplifier as claimed in claim 1, wherein during a calibration phase, the third switching circuit disconnects the path of the current source circuit from the differential pair circuit for the first current and the second current.

5. The preamplifier as claimed in claim 4, wherein during the calibration phase, the third switching circuit further switches the current source circuit to couple to the reference voltage terminal.

6. The preamplifier as claimed in claim 1, wherein during a signal transmission phase, the first switching circuit turns on the path of the differential pair circuit coupled to the first power supply terminal; the current source circuit extracts the non-zero first current and the second current from the differential pair circuit; and the second switching circuit disconnects the coupling path between the first output terminal, the second output terminal and the reference voltage terminal.

7. The preamplifier as claimed in claim 1, wherein during a signal transmission phase, the third switching circuit is used to turn on the coupling path between the differential pair circuit and the current source circuit.

8. The preamplifier as claimed in claim 1, wherein the differential pair circuit includes a first transistor and a second transistor, the load circuit includes a first load and a second load, and the first switching circuit includes a first switch and a second switch, wherein, The first switch and the first load are connected in series between the first terminal of the first transistor and the first power supply terminal; the second switch and the second load are connected in series between the first terminal of the second transistor and the first power supply terminal.

9. The preamplifier as claimed in claim 8, wherein the current source circuit includes a first current source and a second current source, wherein the first current source is coupled between a second terminal of the first transistor and a second power supply terminal, and the second current source is coupled between a second terminal of the second transistor and the second power supply terminal.

10. The preamplifier as claimed in claim 8, wherein the second switching circuit includes a third switch and a fourth switch, the third switch being coupled between the first output terminal and the reference voltage terminal, and the fourth switch being coupled between the second output terminal and the reference voltage terminal.

11. The preamplifier as claimed in claim 8, wherein the third switching circuit includes a fifth switch and a sixth switch, the fifth switch being coupled between a second terminal of the first transistor and a second power supply terminal, and the sixth switch being coupled between a second terminal of the second transistor and a second power supply terminal.

12. The preamplifier as claimed in claim 11, wherein the fifth switch and the sixth switch are further coupled to the reference voltage terminal.

13. An amplifier device, comprising: A first amplifier and a second amplifier, the first amplifier serving as a preamplifier, the second amplifier coupled after the first amplifier, the preamplifier comprising: a differential pair circuit for receiving a first signal and a second signal that are differential signals; a load circuit coupled between a first power supply terminal and a first output terminal and a second output terminal of the preamplifier; a first switching circuit connected in series with the load circuit and coupled between the differential pair circuit and the first power supply terminal; a current source circuit coupled between the differential pair circuit and the second power supply terminal for extracting a first current and a second current from the differential pair circuit; a second switching circuit coupled between the first output terminal, the second output terminal and a reference voltage terminal; and a third switching circuit coupled between the differential pair circuit and the current source circuit.

14. The amplifier device of claim 13, wherein during a calibration phase, the first switching circuit disconnects the path of the differential pair circuit coupled to the first power supply terminal, and the first current and the second current sampled by the current source circuit are 0 amperes.

15. The amplifier device of claim 14, wherein during the calibration phase, the second switching circuit is turned on, such that the first output terminal and the second output terminal are coupled to the reference voltage terminal.

16. The amplifier device as claimed in claim 15, wherein during a calibration phase, the third switching circuit interrupts the path of the current source circuit from which the first current and the second current are captured by the differential pair circuit.

17. The amplifier device as claimed in claim 16, wherein during the calibration phase, the third switching circuit further switches the current source circuit to couple to the reference voltage terminal.

18. The amplifier device of claim 13, wherein during a signal transmission phase, the first switching circuit turns on the path of the differential pair circuit coupled to the first power supply terminal; the current source circuit extracts the non-zero first current and the second current from the differential pair circuit; and the second switching circuit disconnects the coupling path between the first output terminal, the second output terminal and the reference voltage terminal.

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