Abstract: An inductor design on a wafer level package (WLP) does not need to depopulate the solder balls on the die because the solder balls form part of the inductor. One terminal on the inductor couples to the die, the other terminal couples to a single solder ball on the die, and the remaining solder balls that mechanically contact the inductor remain electrically floating. The resulting device has better inductance, direct current (DC) resistance, board-level reliability (BLR), and quality factor (Q).

Abstract: A high power tunable capacitor is disclosed. In an exemplary embodiment, an apparatus includes a capacitor coupled to an input signal, a body contacted switch coupled to the capacitor, the body contacted switch coupled to a body bias signal, and a floating body switch coupled between the body contacted switch and a ground, the floating body switch configured to decouple the body bias signal from the ground.

Abstract: A tunable loadline is disclosed. In an exemplary embodiment, an apparatus includes an amplifier configured to output an amplified signal having a selected power level and a first impedance network coupled to receive the amplified signal at an input terminal and generate a first output signal having a first power level at a first output terminal. The first impedance network being configured to load the amplified signal to convert the selected power level to the first power level. The apparatus also includes a second impedance network configured to selectively receive the first output signal and generate a second output signal having a second power level at a second output terminal. The second impedance network being configured to combine with the first impedance network to load the amplified signal to convert the selected power level to the second power level.

Abstract: Some novel features pertain to a first example provides a semiconductor device that includes a printed circuit board (PCB), asset of solder balls and a die. The PCB includes a first metal layer. The set of solder balls is coupled to the PCB. The die is coupled to the PCB through the set of solder balls. The die includes a second metal layer and a third metal layer. The first metal layer of the PCB, the set of solder balls, the second and third metal layers of the die are configured to operate as an inductor in the semiconductor device. In some implementations, the die further includes a passivation layer. The passivation layer is positioned between the second metal layer and the third metal layer. In some implementations, the second metal layer is positioned between the passivation layer and the set of solder balls.

Abstract: A multi-throw antenna switch with off-state capacitance reduction is disclosed. In an exemplary embodiment, an apparatus is provided that includes a plurality of first stage switches connected to an antenna, and a plurality of second stage switches connected to the plurality of first stage switches, each first stage switch connected in series to one or more second stage switches to form a plurality of switchable signal paths connected to the antenna.

Abstract: A tunable inter-stage matching circuit that can improve performance is described. In an exemplary design, an apparatus comprises a driver amplifier and a power amplifier. The apparatus may further include an inter-stage matching circuit tunable in discrete steps for matching impedances between the driver amplifier and the power amplifier. The tunable inter-stage matching circuit may include a bank of capacitors, each capacitor of the bank coupled in series with a switch for coupling the capacitor to a ground voltage.

Abstract: This disclosure provides systems, methods and apparatus for combining devices deposited on a first substrate, with integrated circuits formed on a second substrate such as a semiconducting substrate or a glass substrate. The first substrate may be a glass substrate. The first substrate may include conductive vias. A power combiner circuit may be deposited on a first side of the first substrate. The power combiner circuit may include passive devices deposited on at least the first side of the first substrate. The integrated circuit may include a power amplifier circuit disposed on and configured for electrical connection with the power combiner circuit, to form a power amplification system. The conductive vias may include thermal vias configured for conducting heat from the power amplification system and/or interconnect vias configured for electrical connection between the power amplification system and a conductor on a second side of the first substrate.

Abstract: Techniques for monitoring and controlling bias current of amplifiers are described. In an exemplary design, an apparatus may include an amplifier and a bias circuit. The amplifier may include at least one transistor coupled to an inductor. The bias circuit may generate at least one bias voltage for the at least one transistor in the amplifier to obtain a target bias current for the amplifier. The bias circuit may generate the at least one bias voltage based on a voltage across the inductor in the amplifier, or a current through a current mirror formed with one of the at least one transistor in the amplifier, or a gate-to-source voltage of one of the at least one transistor in the amplifier, or a voltage in a replica circuit replicating the amplifier, or a current applied to the amplifier with a switched mode power supply disabled.

Abstract: Exemplary embodiments disclosed are directed to power and impedance measurement circuits that may be used to measure power and/or impedance are described. A measurement circuit may include a sensor and a computation unit. The sensor may sense (i) a first voltage signal across a series circuit coupled to a load to obtain a first sensed signal and (ii) a second voltage signal at a designated end of the series circuit to obtain a second sensed signal. The sensor may mix (i) a first version of the first sensed signal with a first version of the second sensed signal to obtain a first sensor output and (ii) a second version of the first sensed signal with a second version of the second sensed signal to obtain a second sensor output. The computation unit may determine the impedance and/or delivered power at the designated end of the series circuit based on the sensor outputs.

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: Techniques for providing adjustable gain in an amplifier. In an aspect, a composite amplifier having adjustable gain includes a plurality of amplifiers coupled in parallel, wherein each of the amplifiers may be turned on or off to adjust the overall gain of the composite amplifier. Each amplifier may include an input transistor and at least two cascode transistors. To turn each amplifier off, the gate voltage of a second or lowermost cascode transistor coupled to the input transistor may be grounded, and the gate voltage of a first cascode transistor coupled to the output voltage may be coupled to a first turn-off voltage to reduce the drain-to-gate voltage drop across the first cascode transistor. Further aspects provide for decoupling a capacitor coupled to the gates of the cascode transistors from AC ground when the amplifier is turned off.

Abstract: Techniques for monitoring and controlling bias current of amplifiers are described. In an exemplary design, an apparatus may include an amplifier and a bias circuit. The amplifier may include at least one transistor coupled to an inductor. The bias circuit may generate at least one bias voltage for the at least one transistor in the amplifier to obtain a target bias current for the amplifier. The bias circuit may generate the at least one bias voltage based on a voltage across the inductor in the amplifier, or a current through a current mirror formed with one of the at least one transistor in the amplifier, or a gate-to-source voltage of one of the at least one transistor in the amplifier, or a voltage in a replica circuit replicating the amplifier, or a current applied to the amplifier with a switched mode power supply disabled.

Abstract: A compact integrated power amplifier is described herein. In an exemplary design, an apparatus includes (i) an integrated circuit (IC) die having at least one transistor for a power amplifier and (ii) an IC package having a load inductor for the power amplifier. The IC die is mounted on the IC package with the transistor(s) located over the load inductor. In an exemplary design, the IC die includes a transistor manifold that is placed over the load inductor on the IC package. The transistor(s) are fabricated in the transistor manifold, have a drain connection in the center of the transistor manifold, and have source connections on two sides of the transistor manifold. The IC die and the IC package may include one or more additional power amplifiers. The transistor(s) for each power amplifier may be located over the load inductor for that power amplifier.

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: Some novel features pertain to a first example provides a semiconductor device that includes a printed circuit board (PCB), asset of solder balls and a die. The PCB includes a first metal layer. The set of solder balls is coupled to the PCB. The die is coupled to the PCB through the set of solder balls. The die includes a second metal layer and a third metal layer. The first metal layer of the PCB, the set of solder balls, the second and third metal layers of the die are configured to operate as an inductor in the semiconductor device. In some implementations, the die further includes a passivation layer. The passivation layer is positioned between the second metal layer and the third metal layer. In some implementations, the second metal layer is positioned between the passivation layer and the set of solder balls.

Abstract: Techniques for generating bias voltages for a multi-cascode amplifier. In an aspect, a multi-cascode bias network is provided, each transistor in the bias network being a replica of a corresponding transistor in the multi-cascode amplifier, enabling accurate biasing of the transistors in the multi-cascode amplifier. In another aspect, a voltage supply for the multi-cascode amplifier is provided separately from a voltage supply for the replica bias network, to advantageously decouple variations in the amplifier voltage supply from the bias network voltage supply. In yet another aspect, the bias voltages of transistors in the multi-cascode amplifier may be configured by adjusting the impedance of resistive voltage dividers coupled to the transistor gate biases. As the gain of the amplifier depends on the bias voltages of the cascode amplifiers, the gain of the amplifier may be adjusted in this manner without introducing a variable gain element directly in the amplifier signal path.

Abstract: Exemplary embodiments are directed to a transmitter with a power amplifier and a switched output matching circuit implementing a plurality of output paths for a plurality of operating modes is described. The power amplifier receives an input RF signal and provides an amplified RF signal. An output matching network performs impedance transformation from low impedance at the power amplifier output to higher impedance at the matching network output. The plurality of output paths are coupled to the output matching network. Each output path provides a different target output impedance for the power amplifier and routes the amplified RF signal from the power amplifier to an antenna when that output path is selected. Each output path may include a matching network coupled in series with a switch. The matching network provides the target output impedance for the power amplifier when the output path is selected. The switch couples or decouples the output path to/from the power amplifier.

Abstract: Techniques for providing adjustable gain in an amplifier. In an aspect, a composite amplifier having adjustable gain includes a plurality of amplifiers coupled in parallel, wherein each of the amplifiers may be turned on or off to adjust the overall gain of the composite amplifier. Each amplifier may include an input transistor and at least two cascode transistors. To turn each amplifier off, the gate voltage of a second or lowermost cascode transistor coupled to the input transistor may be grounded, and the gate voltage of a first cascode transistor coupled to the output voltage may be coupled to a first turn-off voltage to reduce the drain-to-gate voltage drop across the first cascode transistor.

Abstract: An exemplary embodiment disclosed comprises a mixer having a plurality of input leads; a first degenerative impedance element coupled to a first input lead of the mixer; a second degenerative impedance element coupled to a second input lead of the mixer; and a local oscillator (LO) system comprising a plurality of duty cycle modes to generate a LO signal for the mixer, the local oscillator system operates in a first duty cycle based on a first gain state of the mixer, and in a second duty cycle based on a second gain state of the mixer.

Abstract: Techniques to implement a filter for a selected signal path by reusing a circuit component in an unselected signal path are disclosed. In an exemplary design, an apparatus includes first, second, and third circuits. The first circuit passes a first radio frequency (RF) signal to an antenna when a first signal path is selected. The second circuit passes a second RF signal to the antenna when a second signal path is selected. The third circuit is selectively coupled to the first circuit, e.g., via a switch. The first and third circuits form a filter for the second RF signal (e.g., to attenuate a harmonic of the second RF signal) when the second signal path is selected and the first signal path is unselected. The first circuit may include a series inductor, and the third circuit may include a shunt capacitor.