48results about "Switched capacitors control" patented technology

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 low noise amplifier including a variable gain amplifier stage configured to accept an input signal and to provide a load driving signal; a tunable bandpass filter connected as a load to the variable gain amplifier stage, wherein the bandpass filter includes a cross-coupled transistor pair, and at least one cross-coupled compensation transistor pair biased in a subthreshold region configured to add a transconductance component when the load driving signal is of a magnitude large enough to decreases a transconductance of the cross-coupled transistor pair; and, a controller circuit configured to tune the bandpass filter. The filter can be tuned in respect to the frequency and the quality factor Q.

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 apparatus includes an operational amplifier and a plurality of capacitors coupled to an input terminal of the operational amplifier and configured to be selectively coupled to receive one of an input voltage signal and an output voltage signal of the operational amplifier.

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.

A variable matching circuit includes a transformer which is disposed between first and second transistor circuits. A primary inductor device and a secondary inductor device are magnetically coupled in the transformer. The primary inductor device is connected between an output terminal of the first transistor circuit and a bias circuit for the first transistor circuit. The secondary inductor device is connected between an input terminal of the second transistor circuit and a bias circuit for the second transistor circuit. Connection points between the primary inductor device and the bias circuit for the first transistor circuit and between the secondary inductor device and the bias circuit for the second transistor circuit are connected to first and second capacitive elements, respectively. At least one of inductance values of the respective primary and secondary inductor devices and capacitance values of the respective first and second capacitive elements is variable.

One embodiment of the invention may include a programmable gain amplifier comprising an input multiplexer (14) operative to sequentially select input signals (12) for amplification. The input signals may be chosen from a plurality of input signals based on a selection signal. The programmable gain amplifier (18) may include at least one amplifier gain stage operative to apply a variable gain amount to a selected input signal. The programmable gain amplifier may further include a gain mapping component that controls the variable gain amount for each of the selected input signals.

An impedance matching network for a radio frequency (RF) amplifier includes multiple stages connected to each other in a first to last order. A first stage produces an RE output signal, and a last stage receives an RF input signal. Each stage includes a first inductor connected to produce an output signal, a second inductor connected to receive an input signal from a next stage, a capacitor connected between the first and second inductors and a ground. In addition, each stage other than the first stage further includes a first switch to by-pass the first and second inductors, a second switch connected between the first and second inductors and the ground, and a controller for controlling, the first and second switches to select a particular power level of a set of power levels.

An amplification circuit, which may be in a receive path of a communication device, includes an amplifier including at least a first amplification device and a switchable attenuation circuit. The switchable attenuation circuit includes one or more switches and a plurality of attenuation devices and is operable to provide different levels of attenuation to an input signal prior to input to the amplifier depending on the status of the one or more switches. The attenuation devices may be capacitors, wherein the capacitors may be arranged to form a capacitive divider with a level of attenuation dependent on the status of the switches. The switchable attenuation circuit may be a switched capacitive attenuation ladder of n stages, n being any integer, each ladder stage including a capacitive divider. The amplification circuit may also include a switch, which when closed provides an unattenuated path for the input signal to the amplifier input.

An apparatus includes an input terminal to receive a radio frequency (RF) signal and to communicate the RF signal to a low noise amplifier (LNA) via an input signal path, and a capacitor attenuator coupled to the input terminal to attenuate the RF signal by a controllable amount and having a first portion controllable to include a used part configured on the input signal path and an unused part coupled between the input signal path and an AC reference node, and a second portion coupled between the LNA and the AC reference node.

Provided is a current-voltage conversion amplifier circuit including: a plurality of light receiving devices generating a current signal proportional to an amount of light by receiving the light; multipliers amplifying the current signal, converting the amplified current signal into a first voltage signal, outputting the amplified current signal, or outputting the converted first voltage signal; multi input amplifiers outputting first and second output voltage pairs through a process for receiving output values of multipliers and an offset voltage and amplifying the received output values and offset voltage; a multiplexing unit selecting and outputting one first and second output voltage pair among the first and second output voltage pairs outputted from multi input amplifiers; and a signal conversion unit converting a difference value between first and second output voltages outputted from the multiplexing unit and outputting the converted digital signal.

The invention provides a switched capacitor adjustable gain amplifier with high gain and low noise. The switched capacitor adjustable gain amplifier comprises an external signal source, a square wavegenerator, a switched capacitor integrator and a feedback circuit with a signal amplification function, wherein the external signal source and the square wave generator are connected to the switched capacitor integrator, the switched capacitor integrator outputs through the feedback circuit, the switched capacitor integrator comprises seven COMS switching tubes opened by forward pulses, a samplingcapacitor, an adjustable feedback capacitor and an integrating capacitor, and the feedback circuit comprises an operational amplifier. According to the switched capacitor adjustable gain amplifier, the time-reduced integrated frequency of the feedback capacitor is equivalent to the reduction of the capacitance value of the feedback capacitor; the noise of the PGA is reduced while the high gain isrealized; meanwhile, the layout area of the circuit is not increased, the power consumption and the cost are reduced, the detection precision and the detection efficiency of the circuit are improved,and the switched capacitor adjustable gain amplifier is suitable for various sensor interfaces, signal conditioning chips and signal links and has a great market development prospect in automotive electronics, white household appliances, industrial automation and the Internet-of-things.

The present invention relates to an interface circuit for a capacitive accelerometer sensor for measuring an acceleration value sensed by the sensor. The interface circuit comprises a plurality of electrical switches and three programmable capacitors. Two of the programmable capacitors are arranged to implement gain trimming of the interface circuit, while one of the programmable capacitors is arranged to implement acceleration range selection.

An amplification circuit, which may be in a receive path of a communication device, includes an amplifier including at least a first amplification device and a switchable attenuation circuit. The switchable attenuation circuit includes one or more switches and a plurality of attenuation devices and is operable to provide different levels of attenuation to an input signal prior to input to the amplifier depending on the status of the one or more switches. The attenuation devices may be capacitors, wherein the capacitors may be arranged to form a capacitive divider with a level of attenuation dependent on the status of the switches. The switchable attenuation circuit may be a switched capacitive attenuation ladder of n stages, n being any integer, each ladder stage including a capacitive divider. The amplification circuit may also include a switch, which when closed provides an unattenuated path for the input signal to the amplifier input.

This disclosure provides a method for gain control in a wireless receiver. The wireless receiver comprises a first receiver chain adapted to receive a first signal in a first frequency range, a second receiver chain adapted to receive a second signal in a second frequency range, and a common amplifier module operatively connected to the first receiver chain and the second receiver chain. The method comprises determining a first target gain level for a first path comprising the common amplifier module and the first receiver chain, and determining a second target gain level for a second path comprising the common amplifier module and the second receiver chain. The method comprises setting a gain GA of the common amplifier module and a gain GRx1 in the first receiver chain and a gain GRx2 in the second receiver chain based on the first target gain level and the second target gain level.

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.

An amplification circuit configured to generate an output signal by differentially amplifying first and second input signals. The first and second input signals are a differential signal pair. Alternatively, the first input signal is a single-ended signal, and the second input signal is a reference signal. The amplification circuit is configured to perform a differential amplification operation by increasing a gain for generating an output signal based on the first input signal.

An analog front-end circuit for a portable health monitoring device is characterized by comprising a capacitive coupling instrumentation amplifier, a gain programmable amplifier and a band-pass filter. A pre-charging loop composed of a first buffer and a second chopping switch is adopted, a positive feedback loop is composed of a first adjustable capacitor, a second adjustable capacitor and a third chopping switch, and the pre-charging loop and the positive feedback loop are used for impedance enhancement and work in the circuit at the same time, so that the input impedance is greatly improved. The self-calibration module is used for preventing the problem of circuit oscillation possibly caused by impedance improvement; meanwhile, the gain of the programmable gain amplifier is calibrated by using the same calibration logic, and the gain precision of the analog front-end circuit is improved.

Quadrature error correction (QEC) for radio transceivers are provided herein. In certain embodiments, a transceiver includes an in-phase (I) signal path including a first controllable amplifier coupled to a first data converter, and a quadrature-phase (Q) signal path including a second controllable amplifier coupled to a second data converter. The transceiver further includes a QEC circuit operable to correct for a quadrature error between the I signal path and the Q signal path by adjusting a gain of the first controllable amplifier and / or a gain of the second controllable amplifier.

A variable matching circuit includes a transformer which is disposed between first and second transistor circuits. A primary inductor device and a secondary inductor device are magnetically coupled in the transformer. The primary inductor device is connected between an output terminal of the first transistor circuit and a bias circuit for the first transistor circuit. The secondary inductor device is connected between an input terminal of the second transistor circuit and a bias circuit for the second transistor circuit. Connection points between the primary inductor device and the bias circuit for the first transistor circuit and between the secondary inductor device and the bias circuit for the second transistor circuit are connected to first and second capacitive elements, respectively. At least one of inductance values of the respective primary and secondary inductor devices and capacitance values of the respective first and second capacitive elements is variable.

A scalable dynamic range analog-to-digital converter. In one instance, a method of scaling a dynamic range of an analog-to-digital converter is provided. The method includes operating the analog-to-digital converter at a first dynamic range. The method also includes receiving a radio frequency signal and detecting an on-channel signal level of the radio frequency signal. The method also includes when the on-channel signal level is above an on-channel threshold, operating the analog-to-digital converter at a second dynamic range. The method also includes when the on-channel signal level is below the on-channel threshold, operating the analog-to-digital converter at the first dynamic range.

The invention discloses a variable gain amplification circuit for pressure-sensitive touch. The circuit comprises an operational amplification module, a gain configuration module and a clock control module; the clock control module is used for generating a control clock; the gain configuration module is used for configuring gain and output bias voltage according to the control signal, so that an input signal is amplified through reverse operation, superposed with fixed bias voltage and then output; according to the invention, the gain of the amplification circuit is adjusted by adjusting the capacitance value ratio of the input end of an operational amplifier to a feedback branch; the fixed bias amount of the output voltage is changed by adjusting the capacitance value ratio of the input of the operational amplifier to a reference voltage branch; the output signal is only related to the reference voltage, the gain and the input, accurate amplification is obtained when the voltage of the input signal is close to zero, and the problem in amplification when the input signal is close to zero (ground) during light touch in a pressure-resistance change-voltage sensing-based touch schemeis solved.

A programmable gain amplifier has an active load module, a first differential pair, a second differential pair and a current source module; the first differential pair and the second differential module are respectively electrically connected to the active load module; the current source module The first current source terminal of the first differential pair is electrically connected with the second current source terminal of the second differential pair; the current source module is used for providing the first current to the first differential pair through the first current source terminal; the current The source module is used for providing the second current to the second differential pair through the second current source terminal; and the current source module is used for adjusting the magnitude of the first current and / or the magnitude of the second current.

An integrated circuit (IC), comprising: a first gain stage configured to apply a first gain to a first signal to generate a first gain adjusted signal; a first converter configured to convert the first gain adjusted signal to a first converted signal; a second gain stage configured to apply a second gain to the first converted signal to generate a second gain adjusted signal; and a controller configured to coordinate changes in a first gain of the first gain stage and a second gain of the second gain stage to prevent transients in the second gain adjusted signal.

An amplifier circuit that includes a capacitor voltage divider that is selectively enabled with a switch. The circuit includes two capacitor banks where the banks are electrically coupled to opposing side terminals of the switch. When the capacitor voltage divider is not enabled, one bank is adjusted to control the gain of the amplifier. When the capacitor voltage divider is enabled, both banks are used to control the gain of the amplifier.

An apparatus includes a discrete time analog front-end circuit. The discrete time analog front-end circuit includes: a sample and hold circuit; a discrete time linear equalizer circuit having an input coupled to the output of the sample and hold circuit; and a discrete time programmable gain amplifier circuit having an input coupled to the output of the discrete time linear equalizer circuit. The sample and hold circuit is to generate a discrete time modulated signal based at least in part on the continuous time modulated signal. The discrete-time linear equalizer circuit is configured to generate an equalized discrete-time modulated signal based at least in part on the discrete-time modulated signal. The discrete-time programmable gain amplifier circuit is to generate an amplified equalized discrete-time modulated signal based at least in part on the equalized discrete-time modulated signal. A discrete-time analog front-end circuit may include a quantizer circuit having an input coupled to an output of a discrete-time programmable gain amplifier circuit.