Abstract: A power amplifier is provided. The power amplifier includes a first circuit comprising a first transistor and a second transistor coupled respectively to a third transistor and a fourth transistor. The power amplifier also includes a second circuit comprising a transformer having a first winding and a second winding. The first winding comprises a first terminal coupled to the third transistor and a second terminal coupled to the fourth transistor to receive a differential voltage signal with a gain from the first circuit. The second winding comprises a first terminal being grounded and a second terminal serving as an output terminal. The power amplifier circuit further includes a third circuit comprising a programmable capacitor from a midpoint of the first winding to a common node that is coupled to ground. The programmable capacitor is tunable to reduce second harmonic seen at the output terminal.

Abstract: An amplifier may include control circuitry that may track a first input signal parameter and, in response, adjust a value of a second input parameter. Input parameter tracking and adjustment may facilitate control of output parameters for the amplifier. For example, an envelope-tracking amplifier may track input signal amplitude and adjust other input parameters in response. The adjustments may facilitate control of output parameters, such as gain or efficiency. The amplifier may further include calibration circuitry to determine adjustment responses to various tracked input parameters.

Abstract: A fully integrated power amplifier (PA) employing a transformer combiner with enhanced back-off efficiency includes a first PA to amplify a first radio frequency (RF) signal and a second PA to amplify a second RF signal. A first variable capacitor is coupled between differential output nodes of the first PA. A second variable capacitor is coupled between differential output nodes of the second PA. The differential outputs of the first PA and the second PA are coupled via respective first and second transformers to a load. Capacitance values associated with the first and second variable capacitors are dynamically adjustable based on an amplitude of the RF signal to achieve a desired power efficiency at an output power level.

Abstract: A wireless communication device includes a first circuit including a baseband circuit and a radio circuit, and at least one frontend module (FEM) remote from the first circuit and placed in close proximity to and coupled to at least one radio-frequency (RF) antenna. The FEM is coupled to the first circuit via interface circuitry. An FEM comprises a frontend (FE) circuit including one or more low-noise amplifiers (LNAs), one or more power amplifiers (PAs), and at least one of a multi-pole switch and a multiplexer. The multi-pole switch and the multiplexer being implemented on a first side of the FEM coupled to the interface circuitry. The interface circuitry includes at least some of filters, splitters, multi-pole switches, and multiplexers to reduce a count of interconnect routes to the at least one FEM.

Abstract: An amplifier may include control circuitry that may track a first input signal parameter and, in response, adjust a value of a second input parameter. Input parameter tracking and adjustment may facilitate control of output parameters for the amplifier. For example, an envelope-tracking amplifier may track input signal amplitude and adjust other input parameters in response. The adjustments may facilitate control of output parameters, such as gain or efficiency. The amplifier may further include calibration circuitry to determine adjustment responses to various tracked input parameters.

Abstract: A fully integrated power amplifier (PA) employing a transformer combiner with enhanced back-off efficiency includes a first PA to amplify a first radio frequency (RF) signal and a second PA to amplify a second RF signal. A first variable capacitor is coupled between differential output nodes of the first PA. A second variable capacitor is coupled between differential output nodes of the second PA. The differential outputs of the first PA and the second PA are coupled via respective first and second transformers to a load. Capacitance values associated with the first and second variable capacitors are dynamically adjustable based on an amplitude of the RF signal to achieve a desired power efficiency at an output power level.

Abstract: An amplifier may include control circuitry that may track a first input signal parameter and, in response, adjust a value of a second input parameter. Input parameter tracking and adjustment may facilitate control of output parameters for the amplifier. For example, an envelope-tracking amplifier may track input signal amplitude and adjust other input parameters in response. The adjustments may facilitate control of output parameters, such as gain or efficiency. The amplifier may further include calibration circuitry to determine adjustment responses to various tracked input parameters.

Abstract: A transmit/receive switch architecture is provided which reuses a power amplifier's transformer as part of the low noise amplifier (LNA) input matching network. A front-end circuit includes a transmit/receive switch. The transmit/receive switch includes a transformer that includes primary winding and secondary winding. The transmit/receive also includes a transistor, where a drain of the transistor is connected to the secondary winding and a gate of the transistor is configured to receive a control signal. The transmit/receive switch operates as a receive switch when the control signal is low and inputs of the primary winding are either shorted or at open circuit. The transmit/receive switch operates as a transmit switch when the control signal is high.

Abstract: An amplifier may include control circuitry that may track a first input signal parameter and, in response, adjust a value of a second input parameter. Input parameter tracking and adjustment may facilitate control of output parameters for the amplifier. For example, an envelope-tracking amplifier may track input signal amplitude and adjust other input parameters in response. The adjustments may facilitate control of output parameters, such as gain or efficiency. The amplifier may further include calibration circuitry to determine adjustment responses to various tracked input parameters.

Abstract: A wireless communication device includes a first circuit including a baseband circuit and a radio circuit, and at least one frontend module (FEM) remote from the first circuit and placed in close proximity to and coupled to at least one radio-frequency (RF) antenna. The FEM is coupled to the first circuit via interface circuitry. An FEM comprises a frontend (FE) circuit including one or more low-noise amplifiers (LNAs), one or more power amplifiers (PAs), and at least one of a multi-pole switch and a multiplexer. The multi-pole switch and the multiplexer being implemented on a first side of the FEM coupled to the interface circuitry. The interface circuitry includes at least some of filters, splitters, multi-pole switches, and multiplexers to reduce a count of interconnect routes to the at least one FEM.

Abstract: A transmit/receive switch architecture is provided which reuses a power amplifier's transformer as part of the low noise amplifier (LNA) input matching network. A front-end circuit includes a transmit/receive switch. The transmit/receive switch includes a transformer that includes primary winding and secondary winding. The transmit/receive also includes a transistor, where a drain of the transistor is connected to the secondary winding and a gate of the transistor is configured to receive a control signal. The transmit/receive switch operates as a receive switch when the control signal is low and inputs of the primary winding are either shorted or at open circuit. The transmit/receive switch operates as a transmit switch when the control signal is high.

Abstract: A broadband digital transmitter is disclosed. The digital transmitter includes a vector decomposer circuit, a phase selector circuit, and a digital power amplifier (DPA). The vector decomposer circuit receives baseband in-phase (I) and quadrature (Q) signals and decomposes the baseband I and Q signals into an offset envelope signal and a non-offset envelope signal. The phase selector circuit receives a plurality of phase offset local oscillator (LO) signals and outputs, responsive to the baseband I and Q signals, offset LO signals and non-offset LO signals. The DPA processes the offset envelope signal, the non-offset envelope signal, the offset LO signals, and the non-offset LO signals to generate an output signal of the digital transmitter.

Abstract: A broadband digital transmitter is disclosed. The digital transmitter includes a vector decomposer circuit, a phase selector circuit, and a digital power amplifier (DPA). The vector decomposer circuit receives baseband in-phase (I) and quadrature (Q) signals and decomposes the baseband I and Q signals into an offset envelope signal and a non-offset envelope signal. The phase selector circuit receives a plurality of phase offset local oscillator (LO) signals and outputs, responsive to the baseband I and Q signals, offset LO signals and non-offset LO signals. The DPA processes the offset envelope signal, the non-offset envelope signal, the offset LO signals, and the non-offset LO signals to generate an output signal of the digital transmitter.

Abstract: The present disclosure is directed to an envelope tracking supply modulator for multiple PAs. The envelope tracking supply modulator is configured to provide, for each of the multiple PAs, a separate supply voltage that is modulated based on the envelope of the respective RF input signal to the PA. Each of the modulated supply voltages is constructed from a DC component and an alternating current (AC) component. The DC component for each modulated supply voltage is generated by a main switching regulator that is shared by the multiple PAs. In one embodiment, the AC component for each modulated supply voltage is generated by an auxiliary switching regulator that is shared by the multiple PAs and a separate linear regulator for each of the multiple PAs. In another embodiment, the AC component for each modulated supply voltage is generated by a separate buffer.

Abstract: A mixer for a transmitter includes a voltage converter to convert a baseband voltage to a baseband current. A mixer component mixes the baseband current with a local oscillator frequency. An output of the mixer component includes a radio frequency signal and a higher order radio frequency signal. A coupler sends the radio frequency signal and the higher order radio frequency signal to a differential output. A filter is integrated into the coupler to filter the higher order radio frequency signal before being output by the differential output.

Abstract: An electrical balancing network combined with coupled inductors (EBN) replaces a transmit/receive switch was used for isolation for time division duplexing transmission techniques. The EBN allows simultaneous transmit operation, or simultaneous receive operation, of multiple wireless technologies that would otherwise have to be scheduled for transmit or receive in a time division multiplexing manner. The wireless technologies may be WLAN, LTE, Bluetooth or other wireless technologies.

Abstract: A communication device, such as a smart phone, includes an envelope tracking power supply modulator. The envelope tracking power supply modulator receives an envelope tracking reference signal. A baseband controller pre-distorts the envelope tracking reference signal responsive to distortion caused by the envelope tracking power supply modulator. For instance, the pre-distortion may modify the nominal envelope tracking reference signal so that, after the modulator acts on the modified reference signal, the output of the modulator has increased linearity.

Abstract: A communication device, such as a smart phone, includes an envelope tracking power supply. The envelope tracking power supply is configured for direct connection to a supply voltage. The direct connection may be made without connection through an intermediate voltage regulator, such as a low drop out regulator. The supply voltage may be a relatively high battery voltage, for example, that would normally result in greater than permissible voltage limits on the transistors used in conventional envelope tracking power supplies.

Abstract: A system includes a differential circuit, multiple cross-coupled transconductance circuits. In some implementations, the differential circuit may include an inductor coil in a balun or transformer. The cross-coupled transconductance circuits may act to reduce the internal resistance of the differential circuit to increase the quality factor of the differential circuit. The cross-coupled transconductance circuit may be connected at differential points along the differential circuit and be engaged and disengaged to linearize the quality factor of the differential circuit.

Abstract: A communication device, such as a smartphone or tablet, includes a communication interface with noise cancellation logic. The noise cancellation logic includes a lead path and a reference path. A signal source provides a signal to the lead path and the references path. The signal is amplified along the lead path and the reference path. Distortion is imparted onto the signal during amplification on the lead path. A correction signal based on the difference between the amplified signal on the lead path and the amplified signal on the reference path is generated by the noise cancellation logic. The correction signal may reflect to distortion imparted during amplification on the lead path. The correction signal is differentially combined with the amplified signal on the lead path to attempt to remove the distortion and generate an output.