Methods and systems for biasing a power amplifier
View Patent ↗An amplifier circuit including a first transistor and a biasing circuit. The biasing circuit includes a process compensation circuit. The biasing circuit being coupled to a gate of the first transistor. A method for biasing an amplifier circuit is also included.
1. An amplifier circuit comprising:
a first transistor; and
a biasing circuit including a process compensation circuit, the biasing circuit being coupled to a gate of the first transistor:
wherein the process compensation circuit includes a replica device circuit having
a replica transistor that replicates the characteristics of the first transistor, and
a constant current source coupled to the replica transistor.
2. The circuit of claim 1 , wherein the replica transistor is connected as a diode.
3. The circuit of claim 1 , wherein the process compensation circuit and the first transistor are included in a single integrated circuit.
4. An amplifier circuit comprising:
a first transistor; and
a biasing circuit including a process compensation circuit, the biasing circuit being coupled to a gate of the first transistor;
wherein the biasing circuit further includes a bias control circuit coupled to the gate of the first transistor; and
wherein the bias control circuit includes a variable current source coupled to a control circuit.
5. The circuit of claim 4 , wherein the control circuit includes a digital to analog converter.
6. An amplifier circuit comprising:
a first transistor; and
a biasing circuit including a process compensation circuit, the biasing circuit being coupled to a gate of the first transistor;
wherein the biasing circuit further includes a temperature compensation circuit coupled to the gate of the first transistor; and
wherein the temperature compensation circuit includes a temperature proportional current source.
7. The circuit of claim 6 , wherein the temperature compensation circuit and the first transistor are included in a single integrated circuit.
8. The circuit of claim 1 , wherein the amplifier circuit is included within a transmitter.
9. The circuit of claim 1 , wherein the amplifier circuit is included within a wireless data link transmitter.
10. A method of supplying a process compensated DC bias voltage comprising:
generating a current using a constant current source;
producing the process compensated DC bias voltage in a process compensation circuit based on the current; and
applying the process compensated DC bias voltage to a gate of a first transistor, the process compensation circuit and the first transistor being on a single integrated circuit.
11. A method of supplying a process compensated DC bias voltage comprising:
producing the process compensated DC bias voltage in a process compensation circuit; and
applying the process compensated DC bias voltage to a gate of a first transistor, the process compensation circuit and the first transistor being on a single integrated circuit;
wherein the process compensated DC bias voltage is substantially equal to a threshold voltage of the first transistor.
12. The method of claim 10 , further comprising adjusting the process compensated DC bias voltage to select a desired class of operation for the first transistor.
13. The method of claim 12 , wherein adjusting the process compensated DC bias voltage includes receiving a control signal.
14. The method of claim 13 , wherein the control signal includes a digital control signal.
15. The method of claim 14 , wherein receiving the control signal includes converting the digital control signal to an analog signal.
16. The method of claim 10 , further comprising adjusting the process compensated DC bias voltage to compensate for a temperature of the integrated circuit.
17. A data link system comprising:
a first transmitter including an amplifier that includes:
a first transistor; and
a biasing circuit including a process compensation circuits the biasing circuit being coupled to a gate of the first transistors wherein the process compensation circuit and the first transistor are included in a single integrated circuit;
wherein the process compensation circuit includes a replica device circuit having
a replica transistor that replicates the characteristics of the first transistor, and
a constant current source coupled to the replica transistor.
18. A power amplifier circuit comprising:
a first transistor; and
a biasing circuit coupled to a gate of the first transistor, the biasing circuit including:
a process compensation circuit;
a bias control circuit coupled to the gate of the first transistor; and
a temperature compensation circuit coupled to the gate of the first transistor, wherein the process compensation circuit, the temperature compensation circuit and the first transistor are included in a single integrated circuit; and
wherein the temperature compensation circuit includes a temperature proportional current source.