Radio-frequency and bias signal coupling in power amplifier devices
A power amplifier die includes a semiconductor substrate, a power amplifier implemented on the semiconductor substrate, a radio-frequency input configured to receive a radio-frequency input signal having a radio-frequency component and a DC bias component, a bias circuit implemented on the semiconductor substrate, the bias circuit coupled to the power amplifier, and a bias tee circuit implemented on the semiconductor substrate, the bias tee circuit configured to receive the radio-frequency input signal and pass at least a portion of the DC component to the bias circuit and at least a portion of the radio-frequency component to the power amplifier.
1. A power amplifier die comprising:
a semiconductor substrate;
a power amplifier implemented on the semiconductor substrate;
a radio-frequency input configured to receive a radio-frequency input signal having a radio-frequency component and a DC bias component;
a bias circuit implemented on the semiconductor substrate, the bias circuit coupled to the power amplifier; and
a bias tee circuit implemented on the semiconductor substrate, the bias tee circuit configured to receive the radio-frequency input signal and pass at least a portion of the DC component to the bias circuit and at least a portion of the radio-frequency component to the power amplifier.
2. The power amplifier die of claim 1 wherein the bias tee circuit operates to at least partially decouple the radio-frequency component from the DC bias component.
3. The power amplifier die of claim 1 wherein the bias tee circuit includes an inductor coupled to the bias circuit.
4. The power amplifier die of claim 1 further comprising a voltage supply input configured to receive a supply voltage for amplifying an output of the power amplifier.
5. The power amplifier die of claim 1 wherein the DC bias component of the radio-frequency input signal includes a bias current.
6. The power amplifier die of claim 1 wherein the DC bias component of the radio-frequency input signal includes a bias voltage.
7. The power amplifier die of claim 1 wherein the bias circuit includes current mirror circuitry.
8. A power amplifier module comprising:
a packaging substrate configured to receive a plurality of components;
a power amplifier formed on a die that is mounted on the packaging substrate;
a radio-frequency input configured to receive a radio-frequency input signal having a radio-frequency component and a DC bias component;
a bias circuit coupled to the power amplifier; and
a bias tee circuit formed on the die, the bias tee circuit configured to receive the radio-frequency input signal and pass at least a portion of the DC component to the bias circuit and at least a portion of the radio-frequency component to the power amplifier.
9. The power amplifier module of claim 8 wherein the bias tee circuit operates to at least partially decouple the radio-frequency component from the DC bias component.
10. The power amplifier module of claim 8 wherein the bias tee circuit includes a capacitor and a resistor connected in parallel.
11. The power amplifier module of claim 8 wherein the DC bias component of the radio-frequency input signal includes a bias current.
12. The power amplifier module of claim 8 wherein the bias circuit includes a current mirror.
13. A wireless device comprising:
a transceiver configured to process radio-frequency signals;
a power amplifier subsystem communicatively coupled to the transceiver, the power amplifier subsystem including a power amplifier configured to generate an amplified radio-frequency signal;
a radio-frequency node configured to receive a radio-frequency signal having a radio-frequency component and a DC bias component;
a bias circuit coupled to the power amplifier;
a bias tee circuit configured to receive the radio-frequency signal and pass at least a portion of the DC component to the bias circuit and at least a portion of the radio-frequency component to the power amplifier;
a switch connected to the power amplifier subsystem and configured to selectively route the amplified radio-frequency signal to a pole of the switch; and
an antenna in communication with the pole of the switch and configured to facilitate transmission of the amplified radio-frequency signal.
14. The wireless device of claim 13 wherein the power amplifier subsystem further includes a bias signal generator configured to transmit a bias signal on a bias channel, and a radio-frequency transmission channel configured to transmit the radio-frequency signal.
15. The wireless device of claim 14 wherein the power amplifier subsystem further includes a second bias tee circuit coupled to the bias channel and the radio-frequency transmission channel, the second bias tee circuit configured to couple the bias signal with a radio-frequency input signal to form the radio-frequency signal at least in part.
16. The wireless device of claim 14 wherein the bias signal generator is a current generator.
17. The wireless device of claim 14 wherein the bias signal generator is a voltage generator.
18. The wireless device of claim 14 wherein the power amplifier subsystem further includes an input switching module.
19. The wireless device of claim 14 wherein the power amplifier is implemented on a GaAs substrate and the bias signal generator is implemented on a silicon-on-insulator die.
20. The wireless device of claim 14 wherein the power amplifier does not receive a bias signal separately from the radio-frequency node.