Techniques for controlling the output of a power amplifier are disclosed. In one embodiment, the techniques may be realized as a system that includes a power amplifier and a controller coupled to the power amplifier to form a feedback loop. The power amplifier is enabled or disabled in response to a blanking signal. The controller includes an accumulator that stores an accumulated error of the feedback loop. The controller suspends operation of the accumulator when (1) a level of the input signal is below a first threshold for an amount of time that exceeds a second threshold, (2) the blanking signal indicates that the power amplifier is disabled, or (3) both. The controller resumes operation of the accumulator when (1) the level of the input signal is above the first threshold and (2) the blanking signal indicates that the power amplifier is enabled.

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 an 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. Individual inputs can be configured to bypass the variable attenuation in a high gain mode.

Disclosed herein are related to systems and methods for adaptively configuring various components of a wireless device. In one aspect, the wireless device includes a first low noise amplifier, a second low noise amplifier, and an attenuator coupled between the first low noise amplifier and the second low noise amplifier. In one aspect, the wireless device includes one or more processors configured to determine an input power level at the first low noise amplifier. In one aspect, the one or more processors are configured to determine a group of configurations of the first low noise amplifier, the attenuator, and the second low noise amplifier, according to the determined input power level at the first low noise amplifier. In one aspect, the one or more processors are configured to set the first low noise amplifier, the attenuator, and the second low noise amplifier, according to the determined group of configurations.

An amplification circuit includes: an amplifier including a transistor that is connected between an input terminal and an output terminal; an input matching network that is connected between the input terminal and an input side of the amplifier and converts an impedance from a low impedance to a high impedance; a limiter circuit that is connected between a node between the input matching network and the input side of the amplifier, and ground and includes two diodes connected in opposite directions to each other; and a capacitor that is connected in series with the limiter circuit between the node and ground.

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 clamping circuit that may be used to provide efficient and effective voltage clamping in an RF front end. The clamping circuit comprises two series coupled signal path switches and a bypass switch coupled in parallel with the series coupled signal path switches. A diode is coupled from a point between the series coupled signal path switches to a reference potential. In addition, an output selection switch within an RF front end has integrated voltage clamping to more effectively clamp the output voltage from the RF front end. Additional output clamping circuits can be used at various places along a direct gain signal path, along an attenuated gain path and along a bypass path.

Provided is an amplification circuit for amplifying an input signal. The amplification circuit includes an input stage including an input matching circuit that receives the input signal and an input attenuation circuit that attenuates a gain for the input signal outside an operating frequency band of the amplification circuit, a transistor that amplifies the input signal provided from the input stage, and an output stage including an output matching circuit that receives a signal amplified by the transistor and an output attenuation circuit that attenuates the gain for the input signal outside the operating frequency band of the amplification circuit, and the input attenuation circuit includes a first resistor and a second resistor that are connected to a ground voltage, a first passive element connected between the input matching circuit and the second resistor, and a second passive element connected between the first passive element and the first resistor.

A current sense loop includes an attenuator circuit, which has an embedded input chopper circuit, and an amplifier circuit, which has an output chopper circuit. The embedded input chopper has a first chopper input that is coupled to a first attenuator input, a first chopper output that is coupled to a first attenuator output, a second chopper input that is coupled to a second attenuator input, and a second chopper output that is coupled to a second attenuator output. An amplifier has a first input coupled to the first attenuator output and a second input coupled to the second attenuator output. An NFET has a gate coupled to the amplifier output, a source coupled to a ground plane, and a drain coupled to the second attenuator input.

A high-frequency power amplifier is configured in such a way as to include an input matching circuit, an amplifying element, an output matching circuit, a coupling circuit, a detection circuit, and an output terminal, and in such a way that either the input matching circuit or the output matching circuit has an active element, the detection circuit receives a signal outputted by the coupling circuit and outputs a control voltage into which the detection circuit converts the signal to the active element, and the active element changes the impedance of the active element in accordance with the control voltage outputted by the detection circuit, thereby changing the power of a signal outputted by either the input matching circuit having the active element or the output matching circuit having the active element, to change the power of a signal which the coupling circuit outputs to the output terminal.

A gain attenuation circuit that attenuates an input RF signal and transmits the attenuated RF signal to a power transistor is provided. The gain attenuation circuit includes a first diode connected between a first node positioned between a port to which the input RF signal is input and a control terminal of the power transistor, and a ground; a first transistor and a second transistor stacked between a first power source and the ground, and each including a diode-connection structure; and a third transistor configured to receive an operating voltage set by the first transistor and the second transistor through a control terminal, and operate the first diode based on the received operating voltage.