Power amplifier system and associated bias circuit
AssigneeMediatek Inc.
InventorsChien-Wei Tseng, Ming-Da Tsai
Life of this patent
Estimating the term…
Abstract
A power amplifier system includes a differential power amplifier and a bias circuit. The differential power amplifier is arranged for receiving a differential input pair to generate an output signal. The bias circuit is arranged for generating a bias voltage to bias the differential power amplifier, and the bias circuit comprises a source follower for receiving a reference voltage to generate the bias voltage.
Claims21
A power amplifier system, comprising:
- a differential power amplifier, for receiving a differential input pair to generate an output signal;
- a bias circuit, for generating a bias voltage to bias the differential power amplifier, wherein the bias circuit comprises:
- a source follower, for receiving a reference voltage to generate the bias voltage;
- and
- a harmonic rejection circuit, positioned between an output node of the source follower and an input node of the differential power amplifier, for rejecting power amplifier kick-back harmonic(s), wherein the harmonic rejection circuit is implemented by at least a shunt inductor-capacitor (LC) trap or a series LC trap.
A power amplifier system, comprising:
- a power amplifier, for receiving an input signal to generate an output signal;
- a bias circuit, for generating a bias voltage to an input node of the power amplifier, wherein the bias circuit comprises:
- a source follower, for receiving a reference voltage to generate the bias voltage to the input node of the power amplifier;
- and
- a harmonic rejection circuit, positioned between the output node of the source follower and the input node of the power amplifier, for rejecting power amplifier kick-back harmonic(s), wherein the harmonic rejection circuit is implemented by at least a shunt inductor-capacitor (LC) trap or a series LC trap;
- wherein there is no physical resistor positioned between an output node of the source follower and the input node of the power amplifier.
A bias circuit for biasing a differential power amplifier, wherein the differential power amplifier receives the differential input pair from a transformer, and the bias circuit comprises:
- a source follower, for receiving a reference voltage to generate a bias voltage to bias an input terminal of the differential power amplifier;
- and
- a harmonic rejection circuit, positioned between an output node of the source follower and the input node of the differential power amplifier, for rejecting power amplifier kick-back harmonic(s), wherein the harmonic rejection circuit is implemented by at least a shunt inductor-capacitor (LC) trap or a series LC trap.
A power amplifier system, comprising:
- a differential power amplifier, for receiving a differential input pair to generate an output signal;
- a bias circuit, for generating a bias voltage to bias the differential power amplifier, wherein the bias circuit comprises:
- a source follower, for receiving a reference voltage to generate the bias voltage;
- and
- a feedback amplifier, wherein an input node of the feedback amplifier is connected to the output node of the source follower, and an output node of the feedback amplifier is connected to an input node of the source follower.
A bias circuit for biasing a differential power amplifier, wherein the differential power amplifier receives the differential input pair from a transformer, and the bias circuit comprises:
- a source follower, for receiving a reference voltage to generate a bias voltage to a center tap of the transformer to bias the differential power amplifier;
- and
- a feedback amplifier, wherein an input node of the feedback amplifier is connected to the output node of the source follower, and an output node of the feedback amplifier is connected to an input node of the source follower.
Dependencies are inferred from the claim text.