A tunable filter is described where the frequency response as well as bandwidth and transmission loss characteristics can be dynamically altered, providing improved performance for transceiver front-end tuning applications. The rate of roll-off of the frequency response can be adjusted to improve performance when used in duplexer applications. The tunable filter topology is applicable for both transmit and receive circuits. A method is described where the filter characteristics are adjusted to account for and compensate for the frequency response of the antenna used in a communication system.

A control circuit of a power amplifier includes a peak detector, a first comparator, a first current source, a second comparator, a second current source and a bias circuit. The peak detector is arranged for detecting an amplitude of an input signal. The first comparator is arranged for comparing the amplitude of the input signal with a first threshold to generate a first comparing result. The first current source is arranged for generating a first current according to the first comparing result The second comparator is arranged for comparing the amplitude of the input signal with a second threshold to generate a second comparing result. The second current source is arranged for generating a second current according to the second comparing result. The bias circuit is arranged for generating a bias voltage according to the first current and the second current to the power amplifier.

A Doherty amplifier circuit comprising: a splitter having: a splitter-input-terminal for receiving an input signal; a main-splitter-output-terminal; and a peaking-splitter-output-terminal; a main-power-amplifier having a main-power-input-terminal and a main-power-output-terminal, wherein; the main-power-input-terminal is connected to the main-splitter-output-terminal; and the main-power-output-terminal is configured to provide a main-power-amplifier-output-signal; a peaking-power-amplifier having a peaking-power-input-terminal and a peaking-power-output-terminal, wherein: the peaking-power-input-terminal is connected to the peaking-splitter-output-terminal; and the peaking-power-output-terminal is configured to provide a peaking-power-amplifier-output-signal. The splitter, the main-power-amplifier and the peaking-power-amplifier are provided by means of an integrated circuit.

A circuit for implementing a multifunction output generator is described. The circuit comprises an amplifier circuit having a first input and a second input; a voltage generator coupled at a first node to a first input of the amplifier circuit; a controllable current source configured to provide a variable current to the first node; and a switching circuit enabling the operation of the amplifier circuit in a first mode for sensing a temperature and a second mode for providing a reference voltage. A method of implementing a multifunction output generator is described.

A capacitive gain amplifier circuit includes two sets of Miller capacitors and two output stage differential amplifier circuits. A first set of Miller capacitors is used to compensate the first output stage differential amplifier circuit during a first phase that resets the first output stage differential amplifier circuit. The second set of Miller capacitors is used to compensate the first output stage differential amplifier circuit during a second phase that chops a signal being amplified. The second set of Miller capacitors is swapped from one polarity to an opposite polarity of the first output stage differential amplifier circuit during successive second phases. The second output stage differential amplifier circuit includes a set of inputs selectively coupled with the inputs of the first output stage differential amplifier circuit and a set of outputs selectively coupled with the outputs of the first output stage differential amplifier circuit during the second phase.

Certain aspects of the present disclosure generally relate to a multi-output amplifier implemented using a capacitive attenuator. For example, the multi-output amplifier generally includes a first capacitive attenuator coupled to an input node of the multi-output amplifier. In certain aspects, the multi-output amplifier also includes a first amplification stage having an input coupled to a tap node of the first capacitive attenuator and an output coupled to a first output node of the multi-output amplifier, and a second amplification stage having an output coupled to a second output node of the multi-output amplifier. For certain aspects, the multi-output amplifier includes a second capacitive attenuator coupled to the input node of the multi-output amplifier, and the second amplification stage may have an input coupled to a tap node of the second capacitive attenuator.

Certain aspects of the present disclosure generally relate to a multi-output amplifier implemented using a capacitive attenuator. For example, the multi-output amplifier generally includes a first capacitive attenuator coupled to an input node of the multi-output amplifier. In certain aspects, the multi-output amplifier also includes a first amplification stage having an input coupled to a tap node of the first capacitive attenuator and an output coupled to a first output node of the multi-output amplifier, and a second amplification stage having an output coupled to a second output node of the multi-output amplifier. For certain aspects, the multi-output amplifier includes a second capacitive attenuator coupled to the input node of the multi-output amplifier, and the second amplification stage may have an input coupled to a tap node of the second capacitive attenuator.

Processes and systems for producing glass fibers having regions devoid of glass using submerged combustion melters, including feeding a vitrifiable feed material into a feed inlet of a melting zone of a melter vessel, and heating the vitrifiable material with at least one burner directing combustion products of an oxidant and a first fuel into the melting zone under a level of the molten material in the zone. One or more of the burners is configured to impart heat and turbulence to the molten material, producing a turbulent molten material comprising a plurality of bubbles suspended in the molten material, the bubbles comprising at least some of the combustion products, and optionally other gas species introduced by the burners. The molten material and bubbles are drawn through a bushing fluidly connected to a forehearth to produce a glass fiber comprising a plurality of interior regions substantially devoid of glass.

A receiver front end capable of receiving and processing intraband non-contiguous carrier aggregate (CA) signals using multiple low noise amplifiers (LNAs) is disclosed herein. A cascode having a common source input stage and a common gate output stage can be turned on or off using the gate of the output stage. A first switch is provided that allows a connection to be either established or broken between the source terminal of the input stage of each cascode. Further switches used for switching degeneration inductors, gate/sources caps and gate to ground caps for each legs can be used to further improve the matching performance of the invention.

An active device and circuits utilized therewith are disclosed. In an aspect, the active device comprises an n-type transistor having a drain, gate and bulk and a p-type transistor having a drain, gate and bulk. The n-type transistor and the p-type transistor include a common source. The device includes a first capacitor coupled between the gate of the n-type transistor and the gate of the p-type transistor, a second capacitor coupled between the drain of the n-type transistor and the drain of p-type transistor and a third capacitor coupled between the bulk of the n-type transistor and the bulk of p-type transistor. The active device has a high breakdown voltage, is memory less and traps even harmonic signals.