Abstract: Described herein are radio-frequency (RF) modules that include shielding for improved RF performance. The RF modules including a packaging substrate with a receiving system implemented thereon. The RF module includes a shield implemented to provide RF shielding for at least a portion of the receiving system. The receiving system can include any combination of pre-amplifier or post-amplifier bandpass filters, amplifiers, switching networks, impedance matching components, phase-shifting components, input multiplexers, and output multiplexers. The shielding can include a conductive layer within a conformal shielding on an upper side and side walls of the RF module. The shielding can be an overmold formed over the packaging substrate. The conductive layer can be connected to one or more ground planes. The packaging substrate can include contact features on an underside of the substrate for mounting an underside component.

Abstract: Aspects of this disclosure relate to reducing insertion loss associated with a bypass path. In an embodiment, an apparatus includes a first switch having at least two throws, a second switch having at least two throws, a bypass path between the first switch and the second switch, and at least one inductor. The at least one inductor is configured to compensate for capacitance associated with the bypass path to cause insertion loss of the bypass path to be reduced.

Abstract: Disclosed herein are signal amplifiers having a plurality of amplifier cores. Individual amplifier cores can be designed for particular gain modes to enhance particular advantages while reducing other disadvantages. The signal amplifier can then switch between amplifier cores when switching gain modes to achieve desired performance characteristics (e.g., improving noise figure or linearity). Examples of signal amplifiers disclosed herein include amplifier architectures with a high gain amplifier core that reduces the noise figure and a linearity boost amplifier core that increases linearity (e.g., for lower gain modes). The disclosed signal amplifiers have a first active core with amplification chains for each of a plurality of inputs and a second active core with a single amplification chain to amplify signals received at the plurality of inputs.

Abstract: Described herein are variable gain amplifiers that selectively provide variable or tailored impedances at a degeneration block and/or feedback block depending at least in part on a gain mode of the variable gain amplifier. This advantageously reduces or eliminates performance penalties in one or more gain modes. The variable impedances can be configured to improve linearity of the amplification process in targeted gain modes. The variable gain amplifier can be configured to provide a low-loss bypass mode in a low gain mode to improve signal quality. The degeneration block can be selectively isolated from a reference potential node to improve performance.

Abstract: Described herein are variable gain amplifiers and multiplexers that embed programmable attenuators into switchable paths to provide variable gain for individual amplifier inputs. The variable gain for an individual input is provided using a amplification stage that is common for each input of the amplifier. A variable attenuation is provided for individual inputs through a combination of a band selection switch and an attenuation selection branch. The attenuation can be tailored for individual inputs and can depend on a gain mode of the amplifier.

Abstract: Aspects of this disclosure relate to reducing insertion loss associated with a bypass path. In an embodiment, an apparatus includes a first switch having at least two throws, a second switch having at least two throws, a bypass path between the first switch and the second switch, and at least one inductor. The at least one inductor is configured to compensate for capacitance associated with the bypass path to cause insertion loss of the bypass path to be reduced.

Abstract: Diversity receiver front end system with variable-gain amplifiers. A receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input of a first multiplexer and an output of a second multiplexer. The receiving system can further include a plurality of bandpass filters, each one of the plurality of bandpass filters disposed along a corresponding one of the plurality of paths and configured to filter a signal received at the bandpass filter to a respective frequency band. The receiving system can further include a plurality of variable-gain amplifiers (VGAs), each one of the plurality of VGAs disposed along a corresponding one of the plurality of paths and configured to amplify a signal received at the VGA with a gain controlled by an amplifier control signal received from the controller.

Abstract: Disclosed herein are signal amplifiers having a plurality of amplifier cores. Individual amplifier cores can be designed for particular gain modes to enhance particular advantages while reducing other disadvantages. The signal amplifier can then switch between amplifier cores when switching gain modes to achieve desired performance characteristics (e.g., improving noise figure or linearity). Examples of signal amplifiers disclosed herein include amplifier architectures with a high gain amplifier core that reduces the noise figure and a linearity boost amplifier core that increases linearity (e.g., for lower gain modes). The disclosed signal amplifiers can also have switchable reference biases to provide targeted bias current matching. The disclosed signal amplifiers can also include degeneration switching blocks for individual amplifier cores to improve signal linearity.

Abstract: Described herein are variable gain amplifiers and multiplexers that embed programmable attenuators into switchable paths that allow signals in a high gain mode to bypass attenuation. This advantageously reduces or eliminates performance penalties in the high gain mode. The programmable attenuators can be configured to improve linearity of the amplification process through pre-LNA attenuation in targeted gain modes. In addition, described herein are variable gain amplifiers with embedded attenuators in a switching network. The attenuators can be embedded onto switches and can be configured to have little or no effect on a noise factor in a high gain mode because the switching network can provide an attenuation bypass in a high gain mode and an attenuation in other gain modes. The programmable attenuators can be embedded onto a multi-input LNA architecture.

Abstract: Described herein are variable gain amplifiers that selectively provide variable or tailored impedances at a degeneration block and/or feedback block depending at least in part on a gain mode of the variable gain amplifier. This advantageously reduces or eliminates performance penalties in one or more gain modes. The variable impedances can be configured to improve linearity of the amplification process in targeted gain modes. The variable gain amplifier can be configured to provide a low-loss bypass mode in a low gain mode to improve signal quality. The degeneration block can be selectively isolated from a reference potential node to improve performance.

Abstract: Described herein are radio-frequency (RF) modules that include shielding for improved RF performance. The RF modules including a packaging substrate with a receiving system implemented thereon. The RF module includes a shield implemented to provide RF shielding for at least a portion of the receiving system. The receiving system can include any combination of pre-amplifier or post-amplifier bandpass filters, amplifiers, switching networks, impedance matching components, phase-shifting components, input multiplexers, and output multiplexers. The shielding can include a conductive layer within a conformal shielding on an upper side and side walls of the RF module. The shielding can be an overmold formed over the packaging substrate. The conductive layer can be connected to one or more ground planes. The packaging substrate can include contact features on an underside of the substrate for mounting an underside component.

Abstract: Apparatus and methods for distributing spurious tones through the frequency domain are disclosed. One such apparatus can include a dithering circuit configured to generate a sequence of numbers that exhibit statistical randomness and a variable frequency circuit configured to adjust a frequency of an output based on the sequence of numbers so as to spread energy of spurious tones in a frequency response of the output to lower a noise floor. In one example, spurious tones can be reduced in a negative voltage generator of a radio frequency (RF) attenuator.

Abstract: Described herein are variable gain amplifiers that selectively provide variable or tailored impedances at a degeneration block and/or feedback block depending at least in part on a gain mode of the variable gain amplifier. This advantageously reduces or eliminates performance penalties in one or more gain modes. The variable impedances can be configured to improve linearity of the amplification process in targeted gain modes. The variable gain amplifier can be configured to provide a low-loss bypass mode in a low gain mode to improve signal quality.

Abstract: Described herein are radio-frequency (RF) modules that include shielding for improved RF performance. The RF modules including a packaging substrate with a receiving system implemented thereon. The RF module includes a shield implemented to provide RF shielding for at least a portion of the receiving system. The receiving system can include any combination of pre-amplifier or post-amplifier bandpass filters, amplifiers, switching networks, impedance matching components, phase-shifting components, input multiplexers, and output multiplexers. The shielding can include a conductive layer within a conformal shielding on an upper side and side walls of the RF module. The shielding can be an overmold formed over the packaging substrate. The conductive layer can be connected to one or more ground planes. The packaging substrate can include contact features on an underside of the substrate for mounting an underside component.

Abstract: Diversity receiver for wireless applications. In some embodiments, a receiver system can include a controller configured to selectively activate one or more of a plurality of paths between an input and an output, and a plurality of amplifiers, with each one of the plurality of amplifiers disposed along a corresponding one of the plurality of paths and configured to amplify a signal received at the amplifier. The receiving system can further include two or more of features including (a) variable-gain amplifiers, (b) phase-shifting components, (c) impedance matching components, (d) post-amplifier filters, (e) a switching network, and (f) flexible band routing. In some embodiments, such a receiving system can be implemented as a diversity receive module.

Abstract: Diversity receiver front end system with variable-gain amplifiers. A receiving system can include a controller configured to selectively activate one or more of a plurality of paths between an input of a first multiplexer and an output of a second multiplexer. The receiving system can further include a plurality of bandpass filters, each one of the plurality of bandpass filters disposed along a corresponding one of the plurality of paths and configured to filter a signal received at the bandpass filter to a respective frequency band. The receiving system can further include a plurality of variable-gain amplifiers (VGAs), each one of the plurality of VGAs disposed along a corresponding one of the plurality of paths and configured to amplify a signal received at the VGA with a gain controlled by an amplifier control signal received from the controller.

Abstract: Apparatus and methods for digital step attenuators are provided herein. In certain configurations, a DSA includes a plurality of DSA stages that can be set in an attenuation mode or in a bypass mode using a plurality of switching circuits. A first switching circuit of the plurality of switching circuits includes a field effect transistor (FET) switch, a gate resistor, one or more gate resistor bypass switches, and a pulse generation circuit. The gate resistor is electrically connected between a switch control input and a gate of the FET switch, and a switch control signal can be provided to the switch control input to turn on or off the FET switch. In response to detecting a rising and/or falling edge of the switch control signal, the pulse generation circuit can control the one or more gate resistor bypass switches to bypass the gate resistor.

Abstract: Aspects of this disclosure relate to reducing insertion loss associated with a bypass path. In an embodiment, an apparatus includes a first switch having at least two throws, a second switch having at least two throws, a bypass path between the first switch and the second switch, and at least one inductor. The at least one inductor is configured to compensate for capacitance associated with the bypass path to cause insertion loss of the bypass path to be reduced.

Abstract: Disclosed herein are signal amplifiers having a plurality of amplifier cores. Individual amplifier cores can be designed for particular gain modes to enhance particular advantages while reducing other disadvantages. The signal amplifier can then switch between amplifier cores when switching gain modes to achieve desired performance characteristics (e.g., improving noise figure or linearity). Examples of signal amplifiers disclosed herein include amplifier architectures with a high gain amplifier core that reduces the noise figure and a linearity boost amplifier core that increases linearity (e.g., for lower gain modes). The disclosed signal amplifiers can also have switchable reference biases to provide targeted bias current matching. The disclosed signal amplifiers can also include degeneration switching blocks for individual amplifier cores to improve signal linearity.

Abstract: Described herein are variable gain amplifiers and multiplexers that embed programmable attenuators into switchable paths that allow signals in a high gain mode to bypass attenuation. This advantageously reduces or eliminates performance penalties in the high gain mode. The programmable attenuators can be configured to improve linearity of the amplification process through pre-LNA attenuation in targeted gain modes. In addition, described herein are variable gain amplifiers with embedded attenuators in a switching network. The attenuators can be embedded onto switches and can be configured to have little or no effect on a noise factor in a high gain mode because the switching network can provide an attenuation bypass in a high gain mode and an attenuation in other gain modes. The programmable attenuators can be embedded onto a multi-input LNA architecture.