A front end module (FEM) integrated circuit (IC) architecture that uses the same LNA in each of several frequency bands extending over a wide frequency range. In some embodiments, switched impedance circuits distributed throughout the front end circuit allow selection of the frequency response and impedances that are optimized for particular performance parameters targeted for a desired device characteristic. Such switched impedance circuits tune the output and input impedance match and adjust the gain of the LNA for specific operating frequencies and gain targets. In addition, adjustments to the bias of the LNA can be used to optimize performance trade-offs between the total direct current (DC) power dissipated versus radio frequency (RF) performance. By selecting appropriate impedances throughout the circuit using switched impedance circuits, the LNA can be selectively tuned to operate optimally at a selected bias for operation within selected frequency bands.

A phased array element includes a transmit portion having a plurality of amplifier paths, each amplifier path having a driver amplifier and a power amplifier, a first transformer coupled to the power amplifier of a first amplifier path of the plurality of amplifier paths and a second transformer coupled to the power amplifier of a second amplifier path of the plurality of amplifier paths, a secondary winding of each of the first transformer and the second transformer coupled together by a common transformer segment, a transmit phase shifter Sswitchably coupled to the plurality of amplifier paths, a receive portion coupled to the second transformer, the receive portion having a receive path having a low noise amplifier (LNA), and a receive phase shifter coupled to the LNA.

A semiconductor structure for RF applications comprises: a first μTP GaN transistor on an SOI wafer or die; and a first resistor connected to the gate of said first transistor.

A front-end module (FEM) for a 6.1 GHz Wi-Fi acoustic wave resonator RF filter circuit. The device can include a power amplifier (PA), a 6.1 GHz resonator, and a diversity switch. The device can further include a low noise amplifier (LNA). The PA is electrically coupled to an input node and can be configured to a DC power detector or an RF power detector. The resonator can be configured between the PA and the diversity switch, or between the diversity switch and an antenna. The LNA may be configured to the diversity switch or be electrically isolated from the switch. Another 6.1 GHZ resonator may be configured between the diversity switch and the LNA. In a specific example, this device integrates a 6.1 GHz PA, a 6.1 GHZ bulk acoustic wave (BAW) RF filter, a single pole two throw (SP2T) switch, and a bypassable LNA into a single device.

A frontend circuit for a radio frequency (RF) receiver comprises an RF amplifier circuit to receive an RF signal, a local oscillator (LO) circuit to produce a LO signal, a mixer circuit configured to mix the RF signal with the LO signal to produce a down-converted intermediate frequency (IF) signal, a transimpedance amplifier (TIA) circuit to receive the IF signal, and an error reduction circuit operatively coupled to the TIA circuit and configured to reduce voltage error caused by error charge from parasitic capacitance of the frontend circuit.

Methods and systems for a multi gain LNA architecture achieving minimum phase discontinuity between all the different active and passive gain modes that uses different LNA configurations and settings for single and multi-stage LNAs by a configurable combined output matching and phase adjusting circuitry.

A TX/RX switch includes a power amplifier (PA), a Low Noise Amplifier (LNA), and an antenna connection. The PA is connected to a PA matching network that has a PA network impedance and a common PA-LNA impedance connected in one or more series-parallel combinations in different embodiments in a transmitting mode. The LNA is connected to a LNA matching network that has a LNA network impedance and the same common PA-LNA impedance connected in one or more series-parallel combinations in a receive mode. A mode switch can connect the common PA-LNA impedance in different configurations to enable the transmitting and receiving mode respectively. In some embodiments, the mode switch can short or open circuit the connection of the PA matching circuit or the LNA matching circuit to the antenna. In some embodiments, the mode switch can also turn power on or off to the PA or the LNA when the switch is in a mode where the respective amplifier is not selected. Accordingly, with specific design limitations on the common PA-LNA impedance combined with different mode switch configurations of the TX/RX switch components in either the TX or RX mode, the TX/RX switch operates within a design bandwidth without transmission lines embedded in the TX/RX switch circuitry and provides optimum power transfer from/to the antenna at the antenna connection with reduced noise.

A power limiting system and method for a low noise amplifier of a front end interface of a radio frequency communication device. A voltage regulator provides a source voltage to the low noise amplifier having a nominal voltage level that optimizes linearity of the low noise amplifier while a power level of a radio frequency input signal provided to an input of the low noise amplifier does not exceed a predetermined power level threshold. Detection circuitry detects when the power level of a radio frequency input signal exceeds the predetermined power level threshold and provides an adjust signal indicative thereof to the voltage regulator to reduce the source voltage below the nominal voltage level.

A bias circuit for a low noise amplifier of a front end interface of a radio frequency communication device including a bias generator providing a bias voltage on a bias node for the low noise amplifier, a first resistive device coupled between the bias node and an input of the low noise amplifier, a first switch coupled in parallel with the first resistive device, and mode control circuitry receiving a mode signal indicative of a mode change, in which the mode control circuitry, in response to a mode change, momentarily activates the first switch to bypass the first resistive device and momentarily increases current capacity of the bias generator. The mode control circuitry may also momentarily activate a second switch to bypass a second resistive device of the bias circuit. The mode control circuitry may increase a sink current of the bias generator in response to the mode change.

A noise filtering circuit including: an amplifier which receives a reference bias through a first input terminal, generates an amplified output voltage and outputs the amplified output voltage through an output terminal, and receives an output voltage generated on the basis of the amplified output voltage through a second input terminal; a resistance component connected between the output terminal of the amplifier and the second input terminal; and a capacitor connected to the resistance component.