Amplifier device

Abstract

The amplifier device includes a voltage generator, a first amplifier, a second amplifier, and a gain adjuster. The voltage generator generates a first voltage pair and a second voltage pair. The second amplifier amplifies the signal pair at its second input terminal pair based on a gain value to generate an output signal pair, wherein the second amplifier adjusts the gain value according to a gain adjustment signal. During the calibration phase, the gain adjuster generates a gain adjustment signal based on the first voltage pair and the output signal pair. The voltage generator provides the second voltage pair to either the first input terminal pair of the first amplifier or the second input terminal pair of the second amplifier.

Claims

1. An amplifier device, comprising: A voltage generator for generating a first voltage pair and a second voltage pair; A first amplifier having a first input pair; A second amplifier, coupled to the first amplifier, amplifies a signal pair at a second input terminal of the second amplifier based on a gain value to generate an output signal pair, wherein the second amplifier adjusts the gain value according to a gain adjustment signal; a gain adjuster, coupled to the second amplifier and the voltage generator, generates the gain adjustment signal according to the first voltage pair and the output signal pair during the calibration phase, wherein the voltage generator provides the second voltage pair to the first input terminal pair of the first amplifier or the second input terminal pair of the second amplifier; and a switching circuit, coupled to the voltage generator, the first amplifier, and the gain adjuster, wherein the switching circuit is used to provide the second voltage pair to the first amplifier and to the gain adjuster during the calibration phase.

2. The amplifier device as claimed in claim 1, wherein the first voltage pair includes a first voltage and a fourth voltage, the second voltage pair includes a second voltage and a third voltage, wherein a first voltage difference between the fourth voltage and the first voltage is greater than a second voltage difference between the third voltage and the second voltage.

3. The amplifier device as claimed in claim 2, wherein the gain adjuster generates the gain adjustment signal by comparing the first voltage difference with a third voltage difference between the two output signals of the output signal pair.

4. The amplifier device as claimed in claim 3, wherein the gain adjuster comparison includes: A comparison circuit, coupled to the second amplifier and the voltage generator, calculates the first voltage difference and the third voltage difference, and compares the first voltage difference with the third voltage difference to generate a comparison result; And a signal adjustment circuit coupled to the second amplifier and the comparator circuit, adjusting the gain adjustment signal according to the comparison result.

5. The amplifier device as claimed in claim 4, wherein when the comparison result indicates that the third voltage difference is greater than the first voltage difference, the signal adjustment circuit adjusts the gain adjustment signal to increase the gain value.

6. The amplifier device as claimed in claim 4, wherein when the comparison result indicates that the third voltage difference is less than the first voltage difference, the signal adjustment circuit adjusts the gain adjustment signal to reduce the gain value.

7. The amplifier device as claimed in claim 4, wherein the comparator circuit is a fully differential comparator circuit.

8. The amplifier device as claimed in claim 1, wherein the voltage generator includes a resistor string, one end of which receives a first reference voltage and the other end of which receives a second reference voltage, the resistor string generating a first voltage, a second voltage, a third voltage and a fourth voltage sequentially by means of a voltage divider operation based on the first reference voltage and the second reference voltage.

9. The amplifier apparatus of claim 1, wherein the voltage generator includes a resistor string, one end of which receives a first reference voltage and the other end of which receives a second reference current, the resistor string generating a first voltage, a second voltage, a third voltage and a fourth voltage sequentially according to the first reference voltage and the second reference voltage.

10. The amplifier device of claim 9, wherein the switching circuit includes a first chopper and a second chopper, the first chopper causing a first voltage and a fourth voltage of the first voltage pair to be alternately transmitted to a first positive input and a first negative input of the gain adjuster, and the second chopper causing a second voltage and a third voltage of the second voltage pair to be alternately transmitted to a first input and a second input of the first amplifier.

11. The amplifier device as claimed in claim 10, further comprising: A third chopper is coupled between the second amplifier and the gain regulator to transmit a first output signal and a second output signal of the output signal pair to a second positive input terminal and a second negative input terminal of the gain regulator in an alternating manner.

12. The amplifier apparatus of claim 1, wherein the first amplifier comprises: A differential circuit, a load circuit, and a current source circuit, wherein the load circuit, the differential circuit, and the current source circuit are superimposed between a power supply voltage and a reference ground voltage; and a first switching circuit coupled between the load circuit and the power supply voltage, wherein during the correction phase, the first switching circuit disconnects the coupling path between the load circuit and the power supply voltage.

13. The amplifier device as claimed in claim 12, wherein during the correction phase, the current source circuit draws 0 amperes from the differential pair circuit.

14. The amplifier apparatus of claim 12, wherein the first amplifier further comprises: A second switching circuit is coupled between the current source circuit and the reference ground voltage, wherein during the correction phase, the second switching circuit disconnects the coupling path between the current source circuit and the reference ground voltage.

15. The amplifier device as claimed in claim 14, wherein the second switching circuit further causes the differential pair circuit to receive the second voltage pair during the correction phase.

16. The amplifier device as claimed in claim 1, wherein the voltage generator outputs the first voltage pair and the second voltage pair through a plurality of buffers.

Images