Abstract: A communication circuit includes: a first radio frequency (RF) chain configured to output and/or receive a signal of a first frequency band through an antenna port; a second RF chain configured to output and/or receive a signal of a second frequency band through the antenna port; and a switch comprising a first terminal electrically connected to the first RF chain, a second terminal electrically connected to the second RF chain, and a third terminal electrically connected to a ground. The switch is configured to operate in a first operation mode or a second operation mode. In the first operation mode, the first terminal is electrically connected to the second terminal. In the second operation mode, the first terminal is electrically connected to the third terminal.

Abstract: The disclosure relates to a method of detecting whether an external object is in proximity to an electronic device and an electronic device supporting the same. An electronic device according to an embodiment may include: a wireless communication circuit; an antenna electrically connected to the wireless communication circuit and configured to be fed with power from the wireless communication circuit at a first point; a voltage detector including circuitry configured to detect a peak voltage applied to the antenna; and a processor electrically connected to the voltage detector and the wireless communication circuit. The processor may be configured to: determine whether an external object is within a specified proximity to the electronic device based on the peak voltage detected by the voltage detector; and control the magnitude of power applied to the antenna via the wireless communication circuit based on a determination that the external object is within the specified proximity to the electronic device.

Abstract: An adaptive bias circuit for a power amplifier may include a terminal node coupled to the power amplifier. The adaptive bias circuit may also include a low impedance bias circuit coupled to the terminal node. The adaptive bias circuit may further include a high drive bias circuit coupled to the low impedance bias circuit through the terminal node. A separation device may be arranged between the low impedance bias circuit and the high drive bias circuit.

Abstract: A circuit includes a first transistor comprising a gate, a source, and a drain, and an inductor coupled between the gate and the source of the first transistor, wherein the source is further coupled to a current source and the gate is further coupled to an amplifier.

Abstract: An adaptive bias circuit for a power amplifier may include a terminal node coupled to the power amplifier. The adaptive bias circuit may also include a low impedance bias circuit coupled to the terminal node. The adaptive bias circuit may further include a high drive bias circuit coupled to the low impedance bias circuit through the terminal node. A separation device may be arranged between the low impedance bias circuit and the high drive bias circuit.

Abstract: A circuit includes a first transistor comprising a gate, a source, and a drain, and an inductor coupled between the gate and the source of the first transistor, wherein the source is further coupled to a current source and the gate is further coupled to an amplifier.

Abstract: Exemplary embodiments are directed to an amplifier module which may comprise a transmit path including a first amplifier and a second amplifier. The exemplary amplifier module may further include a transformer coupled between the first amplifier and the second amplifier and switchably configured for coupling the first amplifier in series with the second amplifier in a first mode and coupling the first amplifier to bypass the second amplifier in a second mode.

Abstract: Exemplary embodiments are directed to an amplifier module which may comprise a transmit path including a first amplifier and a second amplifier. The exemplary amplifier module may further include a transformer coupled between the first amplifier and the second amplifier and switchably configured for coupling the first amplifier in series with the second amplifier in a first mode and coupling the first amplifier to bypass the second amplifier in a second mode.

Abstract: Exemplary embodiments are related to an envelope-tracking power amplifier. A device may include a first transistor of a plurality of transistors in a stacked configuration configured to receive a supply voltage varying with an envelope of a radio-frequency (RF) input signal. The device may further include a second transistor of the plurality in the stacked configuration coupled to a reference voltage and configured to receive a dynamic bias voltage varying inversely proportional to the supply voltage.

Abstract: Systems and methods may include an amplifier having at least a first input port, where the amplifier includes a first capacitance associated with the first input port; a first bias circuit, where the first bias circuit comprises a series connection of a first charging circuit and a first discharging circuit, wherein a first node between the first charging circuit and the first discharging circuit is connected to the first input port, wherein responsive to an RF input signal having at least a first predetermined level being received at the first input port, the first charging circuit charges the first capacitance associated with the first input port during a first portion of a cycle of the RF input signal, and discharges the first capacitance associated with the first input port during a second portion of the cycle, thereby controlling a DC bias voltage level available at the first input port.

Abstract: Systems and methods may include an amplifier having at least a first input port, where the amplifier includes a first capacitance associated with the first input port; a first bias circuit, where the first bias circuit comprises a series connection of a first charging circuit and a first discharging circuit, wherein a first node between the first charging circuit and the first discharging circuit is connected to the first input port, wherein responsive to an RF input signal having at least a first predetermined level being received at the first input port, the first charging circuit charges the first capacitance associated with the first input port during a first portion of a cycle of the RF input signal, and discharges the first capacitance associated with the first input port during a second portion of the cycle, thereby controlling a DC bias voltage level available at the first input port.

Abstract: Systems and methods may include a low-dropout (LDO) voltage regulator for portable communication devices. The systems and methods may include a comparator having first and second inputs and generating a control voltage, the first input receiving a battery voltage from a battery source, the second input receiving a fixed voltage independent from the battery voltage, and a power management circuit that receives the control voltage and provides a regulated voltage based upon the control voltage, wherein when the received battery voltage is above the fixed voltage, the control voltage is provided at a high constant voltage, thereby resulting in the regulated voltage being at a first voltage, and wherein when the battery voltage is below the fixed voltage, the control voltage is provided at a low constant voltage, thereby resulting in the regulated voltage being at a second voltage less than the first voltage.

Abstract: Systems and methods are provided for overlapping compact multiple transformers.

Abstract: A multi-primary and distributed transformer is provided for one or more sets of parallel-connected or series-connected power amplifiers. The transformer may include a plurality of primary windings, including a first primary winding, a second primary winding, a third primary winding, and a fourth primary winding, where each of the plurality of primary windings is not directly connected to any other of the plurality of primary windings, where each primary winding includes a respective positive port and a negative port for receiving respective differential signals, where each primary winding include a respective first number of turns; and a single secondary winding having a plurality of segments, including a first segment and a second segment, where each segment includes a second number of turns, the second number of turns greater than or equal to the respective first number of turns, where the single secondary winding includes at least one output port.

Abstract: Systems and methods are provided for overlapping compact multiple transformers.

Abstract: A voltage controlled oscillator (VCO) includes a VCO unit having multiple VCO unit output terminals and an amplifier having multiple amplifier output terminals respectively connected to the VCO unit output terminals. The VCO unit generates first output signals having an oscillation frequency corresponding to a supply voltage. The amplifier amplifies a value obtained by performing n-th differentiation on a transconductance component of each first output signal (n being a natural number). Second output signals, corresponding to the first output signals, are output through the amplifier output terminals. Each second output signal includes the amplified value of the corresponding first output signal.

Abstract: A circuit for calibrating a second order intercept point (IP2) and for reducing second order intermodulation (IM2) includes a common mode feedback circuit and a load impedance operatively connected between first and second output terminals of a mixer in a direct conversion receiver. The common mode feedback circuit reduces second order intermodulation of the mixer by detecting an output voltage of the mixer and adjusting a gain of the mixer. The IP2 is controlled by controlling the gain of the common mode feedback circuit. The second order intermodulation (IM2) may be reduced and the linearity of a device may be enhanced.

Abstract: A voltage controlled oscillator (VCO) includes a VCO unit having multiple VCO unit output terminals and an amplifier having multiple amplifier output terminals respectively connected to the VCO unit output terminals. The VCO unit generates first output signals having an oscillation frequency corresponding to a supply voltage. The amplifier amplifies a value obtained by performing n-th differentiation on a transconductance component of each first output signal (n being a natural number). Second output signals, corresponding to the first output signals, are output through the amplifier output terminals. Each second output signal includes the amplified value of the corresponding first output signal.

Abstract: A calibration circuit and method thereof. In the example method, a common-mode voltage may be detected at an output port of a mixer. At least one common-mode feedback voltage may be generated (e.g., at one or more common-mode feedback circuits) based on the detected common-mode voltage. A loop gain may be adjusted in response to a gate control signal (e.g., received at a controller, such as a second order Intecept Point (IP2) controller). An impedance may be adjusted at the output port of the mixer and a current applied to the output port of the mixer may be adjusted based on the at least one common-mode feedback voltage. The example method may be performed by a calibration circuit (e.g., an IP2 calibration circuit).

Abstract: A frequency conversion unit includes a local oscillator, a phase compensator, and a mixer. The local oscillator generates differential original oscillating signals. The phase compensator generates differential compensated oscillating signals mixed with differential received signals by the mixer to generate differential baseband signals. The respective duty cycles of the compensated oscillating signals are adjusted for minimizing intermodulation distortion in the baseband signals.