Linear amplifier and power modulator

Abstract

A linear amplifier includes an amplification stage, a DC level shifting stage, a compensation network, and a power stage. The amplification stage is configured to generate a first signal and a second signal. The DC level shifting stage is configured to adjust a DC voltage of the first signal and a DC voltage of the second signal to generate an adjusted first signal and an adjusted second signal. The compensation network is configured to generate a first drive signal and a second drive signal based on the first signal, the second signal, the adjusted first signal, and the adjusted second signal. The power stage is configured to generate an output signal based on the first drive signal and the second drive signal.

Claims

1. A linear amplifier, characterized in that, include: Amplification stage, used to generate the first and second signals; A DC level offset stage is used to adjust the DC voltage of the first signal and the DC voltage of the second signal to generate an adjusted first signal and an adjusted second signal. A compensation network is configured to generate a first driving signal and a second driving signal based on the first signal, the second signal, the adjusted first signal, and the adjusted second signal; wherein the compensation network performs a high-pass filtering operation on the first signal, a low-pass filtering operation on the adjusted first signal, and combines the high-pass filtering result of the first signal and the low-pass filtering result of the adjusted first signal to generate the first driving signal. as well as, A power stage is used to generate an output signal based on the first drive signal and the second drive signal.

2. The linear amplifier as described in claim 1, characterized in that, The adjusted DC voltage of the first signal is different from the DC voltage of the first signal, and the adjusted DC voltage of the second signal is different from the DC voltage of the second signal.

3. The linear amplifier as described in claim 2, characterized in that, The adjusted DC voltage of the first signal is higher than the DC voltage of the first signal, and the adjusted DC voltage of the second signal is lower than the DC voltage of the second signal.

4. The linear amplifier as described in claim 3, characterized in that, The compensation network generates the first drive signal based on the first signal and the adjusted first signal, and generates the second drive signal based on the second signal and the adjusted second signal; the power stage includes a P-type transistor and an N-type transistor connected in series, the gate of the P-type transistor receiving the first drive signal, and the gate of the N-type transistor receiving the second drive signal.

5. The linear amplifier as claimed in claim 1, characterized in that, The compensation network includes a first feedforward path to retain the AC component of the first drive signal in the first drive signal, and the compensation network includes a second feedforward path to retain the AC component of the second drive signal in the second drive signal.

6. The linear amplifier as claimed in claim 1, characterized in that, The compensation network performs a high-pass filtering operation on the second signal, a low-pass filtering operation on the adjusted second signal, and combines the high-pass filtering result of the second signal and the low-pass filtering result of the adjusted second signal to generate the second driving signal.

7. The linear amplifier as claimed in claim 1, characterized in that, The compensation network includes a first capacitor and a first resistor. A first node of the first capacitor is used to receive the first signal, a first node of the first resistor is used to receive the first adjusted signal, a second node of the first capacitor is coupled to a second node of the first resistor, and a first drive signal is generated at the second node of the first capacitor or the second node of the first resistor.

8. The linear amplifier as claimed in claim 1, characterized in that, The compensation network includes a second capacitor and a second resistor. A first node of the second capacitor is used to receive the second signal, and a first node of the second resistor is used to receive the adjusted second signal. A second node of the second capacitor is coupled to a second node of the second resistor. The second drive signal is generated at the second node of the second capacitor or the second node of the second resistor.

9. The linear amplifier as claimed in claim 1, characterized in that, This amplification stage is a Class AB amplification stage.

10. A power modulator, wherein, The power modulator includes a linear amplifier as described in any one of claims 1 to 9.

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