Bias circuit and amplifier device

A bias circuit comprising:

• a current mirror circuit comprising:
• a reference branch circuit configured to generate a reference current according to a base current;
• and
• at least one mirror branch circuit configured to generate at least one mirrored current according to the reference current, the at least one mirror branch circuit comprising a first mirror branch circuit configured to generate a first mirrored current of the at least one mirrored current and a second mirror branch circuit configured to generate a second mirrored current of the at least one mirrored current;
• an operational amplifier coupled to the reference branch circuit and the at least one mirror branch circuit, and configured to receive a first voltage and a second voltage, and generate a control voltage according to the second voltage, the control voltage being used to adjust the first voltage;
• and
• a bias generation circuit coupled to the at least one mirror branch circuit and configured to generate a bias signal according to the first mirrored current;
• wherein the first voltage is a voltage at the reference branch circuit, and the second voltage is a voltage at the at least one mirror branch circuit or an adjusted voltage thereof.

An amplifier device comprising:

• a first bias circuit comprising:
• a first current mirror circuit configured to receive a first reference voltage, and comprising a first reference branch circuit and at least one first mirror branch circuit, the first reference branch circuit being configured to generate a first reference current according to a first base current, and the at least one first mirror branch circuit being configured to generate at least one first mirrored current according to the first reference current;
• a first operational amplifier coupled to the first reference branch circuit and the at least one first mirror branch circuit, and configured to receive a first voltage and a second voltage, and generate a first control voltage according to the second voltage, wherein the first control voltage is used to adjust the first voltage, the first voltage is a voltage at the first reference branch circuit, and the second voltage is a voltage at the at least one first mirror branch circuit or an adjusted voltage thereof;
• and
• a first bias generation circuit coupled to the at least one first mirror branch circuit and configured to generate a first bias signal according to the at least one first mirrored current;
• an input terminal configured to receive a radio frequency signal;
• an output terminal configured to output an amplified radio frequency signal;
• and
• a first amplifier coupled between the input terminal of the amplifier device and the output terminal of the amplifier device, and configured to receive the first bias signal and amplify the radio frequency signal;
• wherein the amplifier device further comprises:
• a second bias circuit comprising:
• a second current mirror circuit configured to receive the first reference voltage, and comprising a second reference branch circuit and at least one second mirror branch circuit, the second reference branch circuit being configured to generate a second reference current according to a second base current, and the at least one second mirror branch circuit being configured to generate at least one second mirrored current according to the second reference current;
• a second operational amplifier coupled to the second reference branch circuit and the at least one second mirror branch circuit, and configured to receive a third voltage and a fourth voltage, and generate a second control voltage according to the fourth voltage, wherein the second control voltage is used to adjust the third voltage, wherein the third voltage is a voltage at the second reference branch circuit, and the fourth voltage is a voltage at the at least one second mirror branch circuit or an adjusted voltage thereof;
• and
• a second bias generation circuit coupled to the at least one second mirror branch circuit and configured to generate a second bias signal according to the at least one second mirrored current;
• and
• a second amplifier coupled between the input terminal of the amplifier device and the first amplifier, and configured to receive the second bias signal and amplify the radio frequency signal;
• or
• wherein the amplifier device further comprises:
• a third bias circuit comprising:
• a third current mirror circuit configured to receive a second reference voltage, and comprising a third reference branch circuit and at least one third mirror branch circuit, the third reference branch circuit being configured to generate a third reference current according to a third base current, and the at least one third mirror branch circuit being configured to generate at least one third mirrored current according to the third reference current;
• a third operational amplifier coupled to the third reference branch circuit and the at least one third mirror branch circuit, and configured to receive a fifth voltage and a sixth voltage, and generate a third control voltage according to the sixth voltage, wherein the third control voltage is used to adjust the fifth voltage, wherein the fifth voltage is a voltage at the third reference branch circuit, and the sixth voltage is a voltage at the at least one third mirror branch circuit or an adjusted voltage thereof;
• and
• a third bias generation circuit coupled to the at least one third mirror branch circuit and configured to generate a third bias signal according to the at least one third mirrored current;
• a third amplifier coupled between the input terminal of the amplifier device and the first amplifier, and configured to receive the third bias signal and amplify the radio frequency signal;
• a first low-dropout regulator configured to generate the first reference voltage according to a supply voltage;
• and
• a second low-dropout regulator configured to generate the second reference voltage according to the supply voltage.