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.

Variable-phase amplifier circuits and devices. In some embodiments, an amplifier can include a variable-gain stage having a plurality of switchable amplification branches, with each being capable of being activated, such that a combination of one or more activated amplification branches provides respective gain level and phase shift. The plurality of switchable amplification branches can be configured such that the phase shift provided by each combination of one or more activated amplification branches compensates for a phase shift associated with the amplifier operating with the respective gain level of the variable-gain stage.

An amplifier circuit includes an input terminal used to receive an input signal, an output terminal used to output an output signal, an amplification unit, and a phase adjustment unit. The amplification unit includes an input terminal coupled to the input terminal of the amplifier circuit, an output terminal coupled to the output terminal of the amplifier circuit, a first terminal coupled to a first voltage terminal, and a second terminal coupled to a second voltage terminal. The phase adjustment unit is coupled to the amplification unit. When the amplifier circuit is operated in a first mode, the output signal has a first phase, and when the amplifier circuit is operated in a second mode, the output signal has a second phase. A difference between the first phase and the second phase is within a predetermined range.

Methods and devices to fabricate low-cost wideband LNAs that are tunable to multiple frequency bands. Decoupling capacitors are used as part of a tuning circuit implemented at the LNA input. The capacitors are switchably selectable to also tune a signal into desired frequency bands.

A programmable transimpedance amplifier (TIA) includes a plurality of signal paths between an output of a common emitter amplifier and the output of the TIA. The TIA is programmed by selecting one of the signal paths, because the paths have different parameters (e.g. different bandwidth). Thus, the bandwidth or other parameter can be programmed by selecting the appropriate path. The common emitter amplifier's output is coupled to the inputs of common base amplifiers in each path. The inputs have low impedance. Also, each path has a separate buffer amplifying the common base amplifier output in the path. Therefore, having multiple paths does not significantly degrade the amplifier performance. High bandwidth can be provided.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for radio frequency (RF) low noise amplifier (LNA) circuit configured to receive an input RF signal from an RF input source and provide an amplified output RF signal, where the RF LNA circuit includes an amplifier circuit, where the amplifier circuit is configured to receive the input RF signal and provide the amplified output RF signal, and an inductor-degenerated transconductor input impedance circuit that is separate from the amplifier circuit and that is operatively coupled to the input of the amplifier circuit.

A circuit arrangement is provided which includes an array of stages for photon counting current to voltage conversion. Each stage includes a tunable operational transconductance amplifier and a feedback network forming a feedback loop of the operational transconductance amplifier. Each stage is configured to provide an output signal as a function of an input signal that is provided to the amplifier input of the operational transconductance amplifier, wherein the input signal comprises one or more current pulses and the output signal comprises one or more voltage pulses. With the tunable operational transconductance amplifier the transconductance of a stage can be tuned so that differences in peaking time and gain are avoided. Furthermore, an imaging device and a method for operating a circuit arrangement are provided.

The present invention relates to a sensing circuit with signal compensation, which comprises a first sensing element, a second sensing element and a differential amplifying circuit, the differential amplifying circuit generates an output signal through a differential compensation according to a common mode voltage, a first sensing signal and a second sensing signal. Hereby, reducing the noise of the sensing circuit is achieved, and the interference of the display driving signal may be effectively improved.

A power amplifier and power amplification circuit are described herein. An illustrative power amplifier is disclosed to include an input terminal, a drive amplifier connected to the input terminal, and an impedance modulator having a capacitance that is adjusted inversely and proportionately relative to a signal output by the drive amplifier, wherein the impedance modulator provides a feedback loop between an output of the drive amplifier and the input terminal.

A receiver front end amplifier 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” configured input FET and a “common gate” configured output FET can be turned on or off using the gate of the output FET. A first switch is provided that allows a connection to be either established or broken between the source terminal of the input FET of each LNA. Further switches used for switching degeneration inductors, gate capacitors, and gate to ground capacitors for each leg can be used to further improve the matching performance of the invention.