Abstract:
A high power tunable capacitor (500) is disclosed. In an exemplary embodiment, an apparatus includes a capacitor (508) coupled to an input signal (504), a body contacted switch (510) coupled to the capacitor, the body contacted switch coupled to a body bias signal (Bb), and a floating body switch (512) coupled between the body contacted switch and a ground, the floating body switch configured to decouple the body bias signal from the ground.
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:
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:
Certain aspects of the present disclosure provide a semiconductor device. One example semiconductor device generally includes a first semiconductor region; a first non-insulative region disposed adjacent to a first lateral side of the first semiconductor region; a second non-insulative region disposed adjacent to a second lateral side of the first semiconductor region, the second lateral side being opposite to the first lateral side; a second semiconductor region disposed adjacent to a third lateral side of the first semiconductor region, the second semiconductor region and the first semiconductor region having at least one of different doping types or different doping concentrations; an insulative layer adjacent to a top side of the first semiconductor region; and a third non-insulative region, the insulative layer being disposed between the third non-insulative region and the first semiconductor region.
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:
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:
A tunable inter-stage matching circuit that can improve performance is described. In an exemplary design, an apparatus includes a first active circuit (e.g., a driver amplifier), a second active circuit (e.g., a power amplifier), and a tunable inter-stage matching circuit coupled between the first and second active circuits. The tunable inter-stage matching circuit includes a tunable capacitor that can be varied in discrete steps to adjust impedance matching between the first and second active circuits. In an exemplary design, the tunable capacitor includes (i) a plurality of capacitors coupled in parallel and (ii) a plurality of switches coupled to the plurality of capacitors, one switch for each capacitor. Each switch may be turned on to select an associated capacitor or turned off to unselect the associated capacitor. The tunable capacitor may further include a fixed capacitor coupled in parallel with the plurality of capacitors.
Abstract:
A device including a gain control element coupled prior to or within a radio frequency (RF) power amplifier (PA) with an adaptive parametric PA protection circuit is described. In an exemplary embodiment, the device includes a gain control element coupled prior to a radio frequency power amplifier with a power stage with corresponding transistor breakdown threshold values, having an adaptive parametric PA protection circuit configured to receive at least one power stage drain-source voltage parameter value, at least one power stage drain-gate voltage parameter value, and at least one power stage drain-source current parameter value, and including an adaptive parametric PA protection circuit having a first section for processing the parameter values and a second section for generating a gain correction signal to adjust the gain control element with optimal power added efficiency (PAE) for the power stage within the corresponding transistor breakdown threshold values.
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 (580a, 580b, 560a). The first circuit (580a) passes a first radio frequency (RF) signal to an antenna (598) when a first signal path (522a) is selected. The second circuit (580b) passes a second RF signal to the antenna (598) when a second signal path (522b) is selected. The third circuit (560a) is selectively coupled to the first circuit (580a), e.g., via a switch (562a). The first and third circuits (580a, 560a) form a filter for the second RF signal (e.g., to attenuate a harmonic of the second RF signal) when the second signal path (522b) is selected and the first signal path (522a) is unselected. The first circuit may include a series inductor, and the third circuit may include a shunt capacitor.