Class / Patent application number | Description | Number of patent applications / Date published |
330282000 | Having feedback means acting as variable impedance | 30 |
20080224779 | PROGRAMMABLE GAIN AMPLIFIER WITH NOISE CANCELLATION - A wide-band adjustable gain low-noise amplifier (LNA) is disclosed. In various embodiments, the LNA includes a first inverting amplifier configured to generate a first intermediate signal. A first attenuator is configured to receive the first intermediate signal and to generate a second intermediate signal. In various embodiments, the LNA includes a second attenuator configured to generate a third intermediate signal. A second inverting amplifier is configured to generate a fourth intermediate signal using the third intermediate signal. A summing circuit is configured to generate an output signal based on the second and the fourth intermediate signals. Apparatus and methods according to various embodiments of the invention are also disclosed. | 09-18-2008 |
20080231371 | Amplifier Circuit With Adjustable Amplification - An amplifier circuit has an amplifier element having an amplifier element input and an amplifier element input impedance, an amplification adjuster adapted to adjust an amplification of the amplifier element, an amplifier circuit input coupled to the amplifier element input, an impedance element having a alterable impedance value and being coupled to the amplifier circuit input, and an impedance adjuster adapted to adjust the impedance value of the impedance element as a function of the amplification of the amplifier element. | 09-25-2008 |
20080258818 | AMPLIFIER WITH PROGAMMABLE INPUT IMPEDANCE - One embodiment of the invention includes an amplifier system. The amplifier system comprises an amplifier stage configured to receive an input signal at an amplifier input and to provide an amplified output signal. The amplifier system also comprises a programmable input impedance stage comprising a plurality of transconductance stages. At least one of the plurality of transconductance stages can be selectively activated based on a selection signal, the at least one of the activated transconductance stages providing current through the amplifier input that adjusts an impedance associated with the amplifier input based on the amplified output signal. | 10-23-2008 |
20080290947 | RECONFIGURABLE TUNABLE RF POWER AMPLIFIER - A multi-band, multi-standard programmable power amplifier having tunable impedance matching input and output networks and programmable device characteristics. The impedance of either or both of the impedance matching input and output networks is tunable responsive to one or more control signals. In one example, the programmable power amplifier incorporates a feedback control loop and the control signal(s) are varied responsive to the feedback loop. | 11-27-2008 |
20080297258 | Variable impedance circuit; and variable impedance system, filter circuit, amplifier, and communication system using the same - A first transistor includes: a first terminal that receives one of differential input signals; a second terminal that receives a control signal for varying an impedance; a third terminal connected to the second transistor; and a fourth terminal that supplies a potential to a substrate. A second transistor includes: a fifth terminal that receives the other of the differential input signals; a sixth terminal that receives a control signal, the seventh terminal connected to the first transistor, and the eighth terminal that supplies a potential to a substrate. The third terminal, the fourth terminal, the seventh terminal, and the eighth terminal are connected together. | 12-04-2008 |
20090015335 | Variable-Gain Image-Reject Low-Noise Amplifier - A variable-gain amplifier includes an intermediate node operative to receive an electric current from a current source. A common-emitter amplifier has a collector electrically connected to the intermediate node. A first common-base amplifier has an emitter electrically connected to the intermediate node and a collector electrically connected to an output node. A base-degenerated amplifier has an emitter electrically connected to the intermediate node and a collector electrically connected to the output node. A second common-base amplifier has an emitter electrically connected to the intermediate node and a collector electrically connected to small-signal ground. The intermediate node is operative to direct the electric current to the first common-base amplifier, thereby causing the variable-gain amplifier to operate in a first mode; and the intermediate node is operative to direct the electric current to the base-degenerated amplifier and the second common-base amplifier, thereby causing the variable-gain amplifier to operate in a second mode. | 01-15-2009 |
20090091391 | CONFIGURABLE FEEDBACK FOR AN AMPLIFIER - An amplifier is disclosed that includes configurable feedback based on the output of a received signal strength indicator. The feedback may be increased for high received signal levels, and decreased for low received signal levels. In an embodiment, the configurable impedance may comprise a plurality of discrete impedance settings. Amplitude and/or time hysteresis may be incorporated. | 04-09-2009 |
20090160556 | System and Method for Providing a Configurable Inductor Less Multi-Stage Low-Noise Amplifier - In accordance with a particular embodiment of the present invention, an apparatus is offered that includes a configurable feedback low noise amplifier (LNA) connected to a common source connected input transistor to realize a specific value of an input impedance, the input impedance being controlled by transconductance, the overall gain being defined by a global current feedback network. In more specific embodiments, the LNA is used to provide a wide frequency band and a defined input impedance. In other embodiments, the LNA achieves a low noise parameter and low output distortion. Also, the LNA can use a ladder network of grounded switches and floating resistors in order to avoid floating switches in a feedback path. The LNA can increase parametric yield. The LNA can be used to control noise, gain, distortion, and input impedance independently. | 06-25-2009 |
20090243726 | VARIABLE RESISTOR ARRAY AND AMPLIFIER CIRCUIT - A variable resistor array adapted to make a resistance value between a first terminal and a second terminal variable, includes a plurality of resistors connected in series, first through nth MOS transistors selectively connected to the resistors, and first through nth switches having one input terminal connected to the source of the ith MOS transistor, another input terminal connected to a predetermined voltage, and an output terminal connected to a back gate of the ith MOS transistor, and connecting either one of the one input terminal and the other input terminal to the output terminal under control of the ith control signal. The ith switch connects the other input terminal to the output terminal, and the ith switch also connects the one input terminal to the output terminal. | 10-01-2009 |
20090261906 | AMPLIFIER FOR IMPROVING ELECTROSTATIC DISCHARGE CHARACTERISTIC - An amplifier for improving an electrostatic discharge (ESD) characteristic includes an operational amplifier, a first resistor circuit, a first fuse box, a second resistor circuit, and a second fuse box. The operational amplifier includes a first input terminal receiving a first input signal, a second input terminal receiving a second input signal, and an output terminal outputting an output signal. The first resistor circuit is connected between the second input terminal and a first node to prevent ESD from being input to the second input terminal. The first fuse box is connected between the first node and the output terminal of the operational amplifier. The second resistor circuit is connected between the second input terminal and a second node to prevent ESD from being input to the second input terminal. The second fuse box is connected between the second node and a terminal for receiving a ground voltage. | 10-22-2009 |
20090278606 | AGC FOR SLICER-BASED LOW POWER DEMODULATOR - An apparatus and method for performing automatic gain control in a receiver are disclosed. The apparatus may include an amplifier, and the gain control may be based on an output from the amplifier during a time period in which a target signal is not present at the output of the amplifier. | 11-12-2009 |
20100097145 | FEEDBACK CONTROLLED POWER LIMITING FOR SIGNAL AMPLIFIERS - An apparatus is provided. The apparatus includes an amplifier, differential amplifiers, and FETs. The amplifier has an intermediate node and an output node, and the amplifier is adapted to receive an audio signal. Each differential amplifier amplifies the difference between an output voltage from the output node with a reference voltages. The FETs are coupled in series with one another between a first and a second voltage, and each FET receives an output from at least one of the differential amplifiers. Additionally, the intermediate node is coupled to a node between at least two FETs. | 04-22-2010 |
20110181362 | Signal processing circuit - A signal processing circuit includes a waveform shaping section that applies a first gain to an input signal and generates a first signal when an absolute value of a level of the input signal falls within a first input range from a first level to a second level, a variable gain section that adjusts an amplitude of the first signal and amplifies the first signal by a gain to generate an output signal, and a control section that reduces the gain of the variable gain section so that the output signal is prevented from occurrence of clipping when the amplitude of the first signal falls within a second input range. The second input range includes a range of the level of the first signal output from the waveform shaping section corresponding to the first input range of the input signal. | 07-28-2011 |
20130120068 | RADIO FREQUENCY SIGNAL GAIN CONTROL - An RE receiver is described comprising a common gate common source LNA with a variable resistor in the source of the common gate transistor, a variable resistor in the source of the common source transistor, and a variable resistor in the RE input. A Smart Gain Control varies the resistance in the resistors to produce linear amplification in the LNA while maintaining input matching. Further, a broad dynamic range RSSI is described that implements a feedback control loop to maintain signal power within a sensitivity range of the power detector in the RSSI. | 05-16-2013 |
20130169365 | AUTOMATIC GAIN CONTROL FEEDBACK AMPLIFIER - Disclosed is an automatic gain control feedback amplifier that can arbitrarily control a gain even when a difference in input signal is large. The automatic gain control feedback amplifier includes: an amplification circuit unit configured to amplify voltage input from an input terminal and output the amplified voltage to an output terminal; a feedback circuit unit connected between the input terminal and the output terminal and including a feedback resistor unit of which a total resistance value is determined by one or more control signals and a feedback transistor connected to the feedback resistor unit in parallel; and a bias circuit unit configured to supply predetermined bias voltage to the feedback transistor. | 07-04-2013 |
20130271218 | HIGH SPEED TRANSIMPEDANCE AMPLIFIER - A high speed transimpedance amplifier includes an inverting unit, at least one gain module, and a feedback resistor. The inverting unit has an input terminal coupled to a photodiode for receiving an input voltage, and an output terminal for outputting a first voltage. The at least one gain module has an input terminal coupled to the output terminal of the inverting unit for receiving the first voltage, and an output terminal for outputting an output voltage. Each gain module includes a first gain inverting unit and a second gain inverting unit which are coupled to each other. The first gain inverting unit and the second gain inverting unit dominate bandwidth of the high speed transimpedance amplifier. The feedback resistor is coupled to the input terminal of the inverting unit and the output terminal of the at least one gain module for determining a transimpedance of the high speed transimpedance amplifier. | 10-17-2013 |
20130278342 | Broadband Transconductance Amplifier - A transconductance amplifier having an input terminal for receiving an input signal and an output terminal for communicating an output signal based on the input signal, the transconductance amplifier may include a gain transistor and a variable capacitance. The gain transistor may have a gate terminal, a first non-gate terminal, and a second non-gate terminal, the first non-gate terminal coupled to the output terminal of the transconductance amplifier. The variable capacitance may be coupled between the gate terminal of the gain transistor and the second non-gate terminal of the gain transistor. | 10-24-2013 |
20130321083 | Power Supply Regulation for Programmable Gain Amplifier Used in a CMOS Image Sensor - An image sensor array that uses an over saturation sensor to detect when one of the pixels is being oversaturated. When that happens, the power supply to that pixel is prevented from affecting power supplies to the other pixels, by regulating the power supply to the pixel. | 12-05-2013 |
20140077882 | System and Method for a Programmable Gain Amplifier - In accordance with an embodiment, a system includes a programmable gain amplifier having a switchable feedback capacitor coupled in parallel with a first capacitor and a controller. The controller is configured to couple the feedback capacitor between an input node of the programmable gain amplifier and an output node of the programmable gain amplifier in a first gain setting, and switch a first terminal of the feedback capacitor from the output of the programmable gain amplifier to a reference node while a second terminal of the feedback capacitor remains coupled to the input node of the programmable gain amplifier for a first time period when transitioning from the first gain setting to a second gain setting. | 03-20-2014 |
20140097902 | Systems and Methods a High Gain Bandwidth Low Power Trans-Impedance Voltage Gain Amplifier (TIVA) Topology - An amplifier and oscillator system includes a MEMS resonator and a two stage amplifier topology. The MEMS resonator is configured to generate a resonator signal. The two-stage amplifier topology is configured to amplify the resonator signal with a selected trans-impedance gain. Additionally, the two stage amplifier topology yields a feedback resistance that provides the selected trans-impedance gain. | 04-10-2014 |
20140184333 | FEEDBACK AMPLIFIER - Provided is a feedback amplifier. The feedback amplifier includes: an amplification circuit unit amplifying a bust packet signal inputted from an input terminal and outputting the amplified voltage to an output terminal; a feedback circuit unit disposed between the input terminal and the output terminal and controlling whether to apply a fixed resistance value to a signal outputted to the output terminal; a packet signal detection unit detecting a peak value of a bust packet signal from the output terminal and controlling whether to apply the fixed resistance value; and a bias circuit unit generating a bias voltage, wherein the feedback circuit unit determines a feedback resistance value to change the fixed resistance value in response to at least one control signal and adjusts a gain by receiving the bias voltage. | 07-03-2014 |
20140191804 | VARIABLE GAIN AMPLIFIER - A variable gain amplifier ( | 07-10-2014 |
20140266453 | TRANSIMPEDANCE AMPLIFIER (TIA) CIRCUIT AND METHOD - A TIA circuit and method are provided that merge the automatic gain control function with the bandwidth adjustment function to allow the TIA circuit to operate over a wide dynamic range at multiple data rates. The TIA circuit has an effective resistance that is adjustable for adjusting the gain and the bandwidth of the TIA circuit. The mechanism of the TIA circuit that is used to adjust the effective resistance, and hence the gain and bandwidth of the TIA circuit, is temperature independent, and as such, the performance of the TIA circuit is not affected by temperature variations. | 09-18-2014 |
20140285266 | AMPLIFICATION DEVICE AND TRANSMITTER - According to one embodiment, an amplification device includes an input terminal into which an input signal is inputted, a first amplifier, an output terminal, a variable impedance module connected at an output end of the first amplifier, a second amplifier, a reference impedance element connected at an output end of the second amplifier, a magnitude comparator, a phase comparator, and a controller. The controller is configured to control impedance of the variable impedance module so that impedance at a point between the first amplifier and the variable impedance approaches a first value. | 09-25-2014 |
20140300418 | AUTO GAIN ADJUSTING DEVICE AND METHOD THEREOF - An auto gain adjusting device and method is disclosed. The auto gain adjusting device comprises a predistorter, a gain unit, a power amplifier, a receiving unit and a calculation unit. The predistorter generates a plurality of test signals in a calibration mode, wherein the powers between a current test signal and a previous test signal includes a first difference value. The gain unit provides a substantially constant gain value to the current test signal and the previous test signal to generate a current amplified test signal and a previous amplified test signal. The power amplifier amplifies the current amplified test signal and the previous amplified test signal to generate a first transmitting signal and a second transmitting signal. The receiving unit converts the first transmitting signal and the second transmitting signal into a first baseband signal and a second baseband signal respectively. The calculation unit calculates a second difference value between powers of the first baseband signal and the second baseband signal, and compares the second difference value with the first difference value to determine whether the substantially constant gain value causes the plurality of test signals to be operated in a linear region and a compression region of the power amplifier. | 10-09-2014 |
20150061769 | CLOSED LOOP CONTROL SYSTEM, AND AN AMPLIFIER IN COMBINATION WITH SUCH A CLOSED LOOP CONTROL SYSTEM - A control apparatus is provided that can provide high dynamic resolution and is suitable for inclusion within an integrated circuit. The control apparatus receives a demand signal representing a desired value of a measurand, and a feedback signal representing a present value or a recently acquired value of the measurand. The processing circuit forms a further signal a further signal which is a function of the demand and feedback signals. The further signal is then subjected to at least an integrating function. The demand signal, feedback signal or the further signal is processed or acquired in a sampled manner. The use of such sampled, i.e. discontinuous, processing allows integration time constants to be synthesized which would otherwise require the use of unfeasibly large components within an integrated circuit, or the use of off-chop components. Both of these other options are expensive. | 03-05-2015 |
20150116037 | VARIABLE MATCHING CIRCUIT AND 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. | 04-30-2015 |
20150349736 | FEEDBACK AMPLIFIER - Provided herein is a feedback amplifier including an amplifier circuit configured to amplify an input signal input from an input terminal and output the amplified input signal to an output terminal; a feedback circuit configured to apply a feedback resistance value to a signal output to the output terminal, and to control a gain of the amplifier circuit by adjusting the input signal by a bias voltage applied with a feedback resistance value determined; a packet signal sensor configured to generate a fixed resistance control signal for controlling a fixed resistance value included in the feedback resistance value through a comparison between the output from the output terminal with a minimum signal level; and a fixed resistance controller configured to control the fixed resistance value included in the feedback resistance value in response to the fixed resistance control signal. | 12-03-2015 |
20150381123 | SWITCHABLE FEEDBACK CIRCUIT FOR RADIO-FREQUENCY POWER AMPLIFIERS - Switchable feedback circuit for radio-frequency (RF) power amplifiers. In some embodiments, an RF power amplifier (PA) circuit can include a transistor having a base, a collector, and an emitter. The transistor can be configured to amplify an RF signal. The RF PA circuit can further include a switchable feedback circuit implemented between the collector and the base. The switchable feedback circuit can be configured to provide a plurality of resistance values between the collector and the base. Such a PA circuit can be implemented in products such as a die, a module, and a wireless device. | 12-31-2015 |
20150381126 | SWITCHABLE BASE FEED CIRCUIT FOR RADIO-FREQUENCY POWER AMPLIFIERS - Switchable base feed circuit for radio-frequency (RF) power amplifiers. In some embodiments, an RF power amplifier (PA) circuit can include a transistor having a base, a collector, and an emitter, with the transistor being configured to amplify an RF signal. The PA circuit can further include a bias circuit configured to provide a base bias signal to the base of the transistor. The PA circuit can further include a switchable base feed circuit implemented between the bias circuit and the base of the transistor. The switchable base feed circuit can be configured to provide a plurality of different resistance values for the base bias signal between the bias circuit and the base of the transistor. Such a PA circuit can be implemented in products such as a die, a module, and a wireless device. | 12-31-2015 |