Class / Patent application number | Description | Number of patent applications / Date published |
330255000 | Having push-pull amplifier stage | 48 |
20080231364 | AMPLIFYING CIRCUIT HAVING A PULL-UP CIRCUIT AND A PULL-DOWN CIRCUIT FOR INCREASING SLEW RATE - An amplifying circuit includes an operational amplifier, a pull-up circuit and a pull-down circuit. The operational amplifier generates a first pull-up signal, a first pull-down signal and an output signal, wherein the phases of the first pull-up signal and the first pull-down signal are out of phase with the output signal. The pull-up circuit includes a first controlling module for outputting a second pull-up signal according to the first pull-up signal, and a first adjusting module for adjusting the output signal according to the second pull-up signal. The pull-down circuit includes a second controlling module for outputting a second pull-down signal according to the first pull-down signal, and a second adjusting module for adjusting the output signal according to the second pull-down signal. | 09-25-2008 |
20080238545 | LINEARIZED CLASS AB BIASED DIFFERENTIAL INPUT STAGE - A linearized bipolar differential input stage that contains two high gain current mirrors coupled in series with the input voltage signal through the input transistors to allow the output differential current to greatly exceed the DC output current in a Class AB fashion. The extended output current range over and above the DC current significantly lowers the percentage of effects for both DC offset and noise in the output signal path. Non-linearity cancellation is also optimized for the lowest level of input distortion through adjusting transistor area ratios. | 10-02-2008 |
20080265993 | Class AB Rail-to-Rail Input and Output Operational Amplifier - An operational amplifier including an input stage. The input stage may include first and second differential input circuits and a first current mirror. When an input terminal of the operational amplifier is at a positive voltage rail, the first differential input circuit may be activated. When the input terminal is at a negative voltage rail, the second differential input circuit may be activated. In either case, this may cause the first current mirror to provide a current of a predetermined value to each of first and second input terminals of a control circuit, and to each of first and second nodes coupled to a rail-to-rail output stage. The input stage may maintain the current provided to each of the input terminals of the control circuit and to each of the nodes coupled to the rail-to-rail output stage constant over the full input voltage range from the negative voltage rail to the positive voltage rail. | 10-30-2008 |
20080278232 | Operational Amplifier with Rail-to-Rail Common-mode Input and Output Range - An operational amplifier with a rail-to-rail common-mode input and output range comprises a differential input stage consisting of a first differential pair and a second differential pair for receiving an input signal; a summing circuit coupled to the differential input stage for outputting a summation result of the output signals of the first differential pair and second differential pair; and a push-pull output stage coupled to the summing circuit for outputting an amplified signal comprising an output terminal for outputting the amplified signal, a source coupled transistors for generating a control voltage according to output current of the summing circuit, and a first output transistor and a second output transistor for controlling current of the first output transistor and the second output transistor according to the control voltage of the source coupled transistor. | 11-13-2008 |
20090039959 | Differential amplifier, method for amplifying signals of differential amplifier, and display driving device having differential amplifier - A differential amplifier includes input, output, current summing, and switch circuits. The input circuit generates first and second differential currents in response to a voltage difference between differential input signals. The output circuit includes a first and second transistors connected between a first voltage rail and output port and the output port and second voltage rail, respectively. The current summing circuit includes a first control node outputting a first control voltage to control a current in the first transistor and a second control node outputting a second control voltage to control a current in the second transistor, in response to the first and second differential currents, respectively. The switch circuit connects the first transistor gate to one of the first control node and the first voltage rail and the second transistor gate to one of the second control node and the second voltage rail, in response to a control signal. | 02-12-2009 |
20090051431 | HIGH-SWING OPERATIONAL AMPLIFIER OUTPUT STAGE USING ADAPTIVE BIASING - An output stage includes two transistors (switching transistor and biasing transistor) coupled in series in a pullup current path between a VDDA node and an output node, and also includes two transistors (switching transistor and biasing transistor) coupled in series in a pulldown current path between the output node and a ground node. Providing the biasing transistors reduces the maximum voltage dropped across the transistors, thereby allowing the transistors to have lower breakdown voltages than VDDA. An adaptive biasing circuit adjusts the gate voltage on a biasing transistor based on the output node voltage. If the output voltage is in a midrange, then the gate voltage is set farther away from a rail voltage in order to reduce voltage stress. If the output voltage is in a range closer to the rail voltage, then the gate voltage is set closer to the rail voltage, thereby facilitating rail-to-rail output voltage swings. | 02-26-2009 |
20090051432 | High-bandwidth high-gain amplifier - A pipelined analog to digital converter includes a first stage that receives an input voltage, that generates a first sampled digital value and a first residue voltage, and that includes a first amplifier that amplifies the first residue voltage and generates a first amplified residue voltage. A second stage receives the first amplified residue voltage, generates a second sampled digital value and a second residue voltage, and includes a second amplifier that amplifies the second residue voltage. At least one of the first amplifier and the second amplifier comprises a first transistor having a control terminal, a first terminal, and a second terminal, a second transistor having a control terminal, a first terminal, and a second terminal that communicates with the second terminal of the first transistor, a differential transimpedance amplifier and a differential output amplifier. | 02-26-2009 |
20090066416 | Push-pull amplifier - A push-pull amplifier is provided which, without depending on the overdrive voltage, can increase the peak value of the gate voltage for the output transistor to a level still higher than the conventional one, and is capable of producing an output current with low consumption current that is higher than that available with conventional push-pull amplifiers. The present invention includes a differential amplifier | 03-12-2009 |
20090091388 | Apparatus for slew rate enhancement of an operational amplifier - The present invention discloses an apparatus for slew rate enhancement of an operational amplifier, wherein an auxiliary control device and an auxiliary output device are added to the output stage of an operational amplifier. The auxiliary control device mirrors the current of the output stage and then compares the mirrored current with a reference current to generate an auxiliary push/pull control signal, which is used to control the auxiliary output device. When the output signal is different from the input signal, the auxiliary control device turns on the auxiliary output device to provide an auxiliary output current for the output terminal. When the output signal is equal to the input signal, the auxiliary output device is turned off. | 04-09-2009 |
20090115519 | POWER AMPLIFIER AND ITS IDLING CURRENT SETTING CIRCUIT - An idling current setting circuit ( | 05-07-2009 |
20090140811 | AMPLIFYING CIRCUIT - First and second voltage buffers are added to an amplifying circuit including input and output amplifying stages in which a P-MOS transistor and an N-MOS transistor operate as a push-pull circuit. An input of the first voltage buffer is connected to an output of the amplifying circuit, and an output of the first voltage buffer is connected via a first phase compensating capacitor to a gate electrode of the P-MOS transistor, and is connected via a second phase compensating capacitor to a gate electrode of the N-MOS transistor. An input of the second voltage buffer is connected to the output of the amplifying circuit, and an output of the second voltage buffer is connected via a third phase compensating capacitor to the gate electrode of the P-MOS transistor, and is connected via a fourth phase compensating capacitor to the gate electrode of the N-MOS transistor. | 06-04-2009 |
20090146738 | OPERATIONAL AMPLIFIER - The operational amplifier adapting to a source driver is provided herein. The operational amplifier includes the input module, the first and the second current mirror module, the switch control module and output stage module, wherein the input module includes the first and the second differential pairs. The first current mirror module provides the first bias current to the first differential pairs and outputs the first mirrored current. The second current mirror module receives the second bias currents and the second mirrored current from the second differential pairs. The first and the second mirrored currents are respectively generated by mirroring the first and the second bias currents. The switch control module adjusts the first and the second bias currents for controlling the operation of the output stage module. The output stage module generates an output voltage terminal to a panel load according to the first and the second mirrored currents. | 06-11-2009 |
20090251215 | AMPLIFIER OUTPUT STAGE WITH EXTENDED OPERATING RANGE AND REDUCED QUIESCENT CURRENT - An output stage of an amplifier circuit includes one or more output transistors that are selectively driven by a boosted drive circuit, where the boosted drive circuit is arranged such that the output range of the amplifier circuit is increased while maintaining reduced quiescent current. The drive signal to each output transistor is selectively increased only when demanded by the output load conditions. The threshold for boosting the drive signal can be adjusted for optimized performance. In one example, a class AB output stage includes a separate drive boost circuit for each output transistor. For this example, each drive boost circuit has a separate threshold for boosting each of the drive signals to the output transistors. The boosting can also be adjusted to optimize the differential input stage and current mirror maximum current requirement while maintaining minimum required bias currents. | 10-08-2009 |
20090278602 | CLOSED LOOP SURGE PROTECTION TECHNIQUE FOR DIFFERENTIAL AMPLIFIERS - A differential amplifier with surge protection is described. The differential amplifier includes a first output driver device, a second output driver device, a first replica device, a second replica device, a current comparator, and a clamp circuit. The first replica device is configured to be a replica of the first output driver device. The second replica device is configured to be a replica of the second output driver device. The current comparator is configured to generate a threshold current, and to compare the threshold current to a first current through the first replica device and a second current through the second replica device. The clamp circuit is configured to limit a third current through the first output driver device and a fourth current through the second output driver device if the current comparator determines that the threshold current is greater than the first current or the second current. | 11-12-2009 |
20100001799 | AMPLIFIER CURRENT DRIVE REVERSAL - A drive current direction between first and second amplifiers can be selected using a received indication of an output current in an at least partially reactive load, and an amplified output signal can be produced using the selected drive current direction and the first and second amplifiers. Further, the first and second amplifiers can be configured to alternate between a pull-up mode and a pull-down mode, each amplifying half of a full wave output signal. | 01-07-2010 |
20100148869 | POWER AMPLIFICATION CIRCUIT HAVING TRANSFORMER - In order to realize a wider bandwidth of a frequency characteristic of a power amplification circuit, outputs of differential push-pull amplifiers which are matched at respectively different frequencies are combined together by secondary inductors, and the combined signal is outputted. | 06-17-2010 |
20100164625 | Slew-Rate-Enhanced Error Amp with Adaptive Transconductance and Single Dominant Pole Shared by Main and Auxiliary Amps - An error amplifier can be used to control a power regulator transistor. The error amplifier has a main amplifier, a pull-up auxiliary amplifier, and a pull-down auxiliary amplifier that all drive an output. A compensating capacitor on the output sets a single dominant pole for all amplifiers, increasing stability. High slew rates are provided by increased slew current from the auxiliary amplifiers that turn on when the differential input has an absolute voltage difference larger than an intentional offset. The intentional offset is introduced into the auxiliary amplifiers by adjusting a p-channel to n-channel transistor ratio in a leg of the auxiliary amplifiers. A source degenerated resistor in the main amplifier reduces supply headroom and increases linearity by connecting sources of two differential transistors that receive the differential input. Cascode transistors increase gain and output impedance. Reliability is increased as no positive feedback is used in the amplifiers. | 07-01-2010 |
20110050342 | Push-pull amplifier circuit and operational amplifier circuit using the same - A push-pull amplifier including first to third current paths. The first current path includes first transistor allowing first current to flow through the first current path according to input signal. The second current path includes second transistor allowing second current having opposite phase to the first current to flow through the second current path according to the first current; first resistor; and third transistor connected to one end of the first resistor and having control terminal connected to the other end of the first resistor. The third current path includes output terminal; fourth transistor allowing current having the same phase as the first current to flow through the third current path according to the input signal; and fifth transistor allowing current having the same phase as the second current to flow through the third current path according to voltage of first node between the first resistor and the third transistor. | 03-03-2011 |
20110285465 | OPERATIONAL AMPLIFIER HAVING A COMMON MODE FEEDBACK CIRCUIT PORTION - An operational amplifier that can suppress lowering of the current driving capability while performing a self adjustment of the common mode voltage is disclosed. A common mode voltage adjusting transistor and an auxiliary transistor are connected in parallel with a low-voltage side drive transistor of each of push-pull amplifying circuits that produce first and second amplified difference signals having different polarities in accordance with drive signals obtained by level-shifting a difference signal indicating a difference value of the levels of the first and second input signals by predetermined values. Current drive capabilities during a period of outputting said first and second amplified difference signals and a common mode voltage adjusting period respectively are increased by driving said auxiliary drive transistor by alternately using the drive signal obtained by level-shifting the difference signal and a common mode voltage adjusting signal. | 11-24-2011 |
20110316630 | PUSH-PULL LINEAR HYBRID CLASS H AMFLIER - Several push-pull linear hybrid class H amplifiers are disclosed. A split power rail provides a positive supply rail and a negative supply rail in response to a power supply control voltage. A push-pull amplifier stage is powered by the positive and negative supply rails. The amplifier stage receives an input signal and provides a corresponding amplified output signal. A power supply control circuit provides the power supply control voltage in response to the smaller of the positive and negative supply rails, and the input signal. | 12-29-2011 |
20120092070 | ACOUSTIC PSEUDO-TRIODE CHARACTERISTIC AMPLIFICATION DEVICE AND ACOUSTIC PSEUDO-TRIODE CHARACTERISTIC PUSH-PULL AMPLIFICATION DEVICE - An input terminal is connected to a positive-phase terminal of a differential amplification circuit. A negative-phase terminal of the differential amplification circuit is connected to an emitter electrode of a transistor, and an output terminal thereof is connected to a base electrode of the transistor. An input side resistor is connected between a collector electrode of the transistor and the input terminal, and a secondary input side resistor is connected between the input terminal and a ground conductor. An output side resistor is connected between the emitter electrode of the transistor and the ground conductor. The collector electrode of the transistor is connected to a load terminal. | 04-19-2012 |
20120112836 | OPERATIONAL AMPLIFIER - An operational amplifier includes a differential amplifier input stage that supplies an operating current to a differential pair, the differential amplifier input stage including a first transistor having a first polarity, a push-pull amplifier output stage that includes a second transistor having the first polarity, and a third transistor having a second polarity, the second transistor and the third transistor being connected in series, a first capacitive element that connects a gate of the first transistor and a gate of the second transistor, and a second capacitive element that connects the gate and a drain of the first transistor. | 05-10-2012 |
20120119834 | AMPLIFIER CIRCUIT WITH OVERSHOOT SUPPRESSION - An amplifier circuit with overshoot suppress scheme including an input amplifier, an output amplifier, and a diode is provided. A first and a second input ends of the output amplifier are coupled to a differential output pair of the input amplifier. The diode is coupled between an output end and the first input end of the output amplifier. When the voltage difference between the output and the input ends of the output amplifier is greater then the barrier voltage of the diode, the diode is turned on, so that the output end of the output amplifier is coupled to the input end of the output amplifier. In the transient state, it rapidly smoothes the overshoot signal. In the steady state, the diode is cut off to maintain the normal operation of the operational amplifier. | 05-17-2012 |
20120161871 | CMOS Push-Pull Power Amplifier With Even-Harmonic Cancellation - A power amplifier includes a push-pull pair of transistors including a first transistor inductively coupled to a voltage source and coupled to a ground, and a second transistor inductively coupled to the ground and coupled to the voltage source. Gates of the first and the second transistors are AC inputs configured to receive an AC signal having a fundamental frequency. Drain regions of the first and the second transistors are, respectively, first and second output nodes. The power amplifier further includes a capacitor coupled between the first output node and the second output node and where the capacitor is configured as a pathway for cancellation of even harmonic signals of the fundamental frequency of the AC signal. | 06-28-2012 |
20120182072 | Self-Biasing Radio Frequency Circuitry - The present disclosure describes self-biasing radio frequency circuitry. In some aspects a radio frequency (RF) signal is amplified via a circuit having a first transistor configured to source current to an output of the circuit and a second transistor configured to sink current from the output of the circuit, and another signal is provided, without active circuitry, from the output of the circuit to a gate of the first transistor effective to bias a voltage at the output of the circuit. By so doing, the output of the circuit can be biased without active circuitry which can reduce design complexity of and substrate area consumed by the circuit. | 07-19-2012 |
20130069723 | POWER AMPLIFICATION CIRCUIT HAVING TRANSFORMER - In order to realize a wider bandwidth of a frequency characteristic of a power amplification circuit, outputs of differential push-pull amplifiers which are matched at respectively different frequencies are combined together by secondary inductors, and the combined signal is outputted. | 03-21-2013 |
20130106514 | HIGH VOLTAGE DRIVER AMPLIFIER FOR PIEZO HAPTICS | 05-02-2013 |
20130135050 | AMPLIFIER - A differential electronic amplifier including: a first switch connected between a first reference voltage and a first node; a second switch connected between a second reference voltage and a second node; a resonant differential load connected between the first and second nodes and having a centre point connected to a third reference voltage; an output stage constituted by a first side of a transformer; a load impedance connected to a second side of the transformer; a first capacitive element connected between the first side of the transformer and the first node; and a second capacitive element connected between the first side of the transformer and the second node; wherein all inductive elements connected in series between the first and second capacitive elements are inductively coupled to the second side of the transformer. | 05-30-2013 |
20130147558 | BUFFER CIRCUIT - A buffer circuit includes an amplification unit configured to amplify and output a difference between an input signal and a reference voltage; and a driver configured to drive an output node in response to the output of the amplification unit and be controlled in at least one of a pull-up driving strength and a pull-down driving strength at the output node in response to the reference voltage. | 06-13-2013 |
20130169362 | INPUT CLAMPING STRUCTURE FOR SOUND QUALITY IMPROVEMENT IN CAR-RADIO CLASS-AB POWER AMPLIFIER DESIGN - A clamping circuit for a class AB amplifier includes a reference voltage circuit, four NPN Darlington transistors having inputs coupled to the reference voltage circuit, and outputs for providing four clamped voltages, and a split NPN Darlington transistor having an input coupled to the reference voltage circuit, and four separate outputs for providing four AC ground voltages. | 07-04-2013 |
20130265109 | POWER AMPLIFICATION CIRCUIT HAVING TRANSFORMER - In order to realize a wider bandwidth of a frequency characteristic of a power amplification circuit, outputs of differential push-pull amplifiers which are matched at respectively different frequencies are combined together by secondary inductors, and the combined signal is outputted. | 10-10-2013 |
20130300504 | BIAS CONTROL FOR PUSH-PULL AMPLIFIER ARRANGEMENT - An amplification stage comprising: a combiner to generate a sum input signal by combining a voltage signal with a DC bias voltage; a subtractor to generate a difference input signal by subtracting the voltage signal from the DC bias voltage; a first transistor for generating a first part of an amplifier output signal from the sum input signal; a second transistor for generating a second part of an amplifier output signal from the difference input signal; a combiner for combining the first and second parts of the amplifier output signal; a sensing circuit arranged to sense a current flowing in each of the first and second transistors; a control circuit arranged to determine the quiescent current of the first and second transistors in dependence on the sensed currents; and an adjustment circuit arranged to adjust the DC bias voltage in order to minimise variation in the quiescent current. | 11-14-2013 |
20130300505 | RF POWER AMPLIFIER - A reduction is achieved in the primary-side input impedance of a transformer (voltage transformer) as an output matching circuit without involving a reduction in Q-factor. An RF power amplifier includes transistors, and a transformer as the output matching circuit. The transformer has a primary coil and a secondary coil which are magnetically coupled to each other. To the input terminals of the transistors, respective input signals are supplied. The primary coil is coupled to each of the output terminals of the transistors. From the secondary coil, an output signal is generated. The primary coil includes a first coil and a second coil which are coupled in parallel between the respective output terminals of the transistors, and each magnetically coupled to the secondary coil. By the parallel coupling of the first and second coils of the primary coil, the input impedance of the primary coil is reduced. | 11-14-2013 |
20140077879 | Push-Pull Amplifier and Differential Push-Pull Amplifier - A push-pull amplifier includes an amplifier input, a push amplifier stage, a pull amplifier stage and an inverting amplifier output. | 03-20-2014 |
20140097898 | Electronic Circuit - An electronic circuit for amplifying a wanted signal, comprising: a comparator having a first input, a second input and an output, wherein a connection is provided, which leads the wanted signal to the first input; a first driver stage comprising an input and an output, wherein the first driver stage includes at least a first push pull end stage; a low-pass filter having an input and an output, wherein the output of the first driver stage leads to the input of the low pass filter; a first feedback network; and a second feedback network. | 04-10-2014 |
20140103999 | AMPLIFIER, FULLY-DIFFERENTIAL AMPLIFIER AND DELTA-SIGMA MODULATOR - An amplifier includes a front-end gain stage and an AC-coupled push-pull output stage. The AC-coupled push-pull output stage includes a first transistor, having a source, a drain and a gate, wherein the source of the first transistor is coupled to a first voltage level; a second transistor, having a source, a drain and a gate, wherein the source of the second transistor is coupled to a second voltage level, the gate of the second transistor is coupled to the front-end gain stage, and the drain of the second transistor is coupled to the drain of the first transistor to form an output terminal of the amplifier; an AC-coupled capacitor, which is a passive two terminal electrical component coupled between the front-end gain stage and the gate of the first transistor; | 04-17-2014 |
20140197887 | Telescopic OP-AMP With Slew Rate Control - An operational amplifier includes a transfer circuit, a cascode control circuit, and a slew rate boost circuit. The transfer circuit is configured to apply a transfer function to a received input signal and the application of the transfer function to the received input signal is effective to create an output signal. The cascode circuit is coupled to the transfer circuit. The cascode circuit is configured to increase an open loop gain of the operational amplifier. The slew rate boost circuit is coupled to the cascode circuit. The slew rate boost circuit is configured to increase the slew rate of the operational amplifier without necessarily increasing the power consumption of the operational amplifier. | 07-17-2014 |
20140203874 | POWER AMPLIFIERS WITH PUSH-PULL TRANSISTORS, CAPACITIVE COUPLING FOR HARMONIC CANCELLATION, AND INDUCTIVE COUPLING TO PROVIDE DIFFERENTIAL OUTPUT SIGNALS - A differential power amplifier including a push-pull pair of transistors, a capacitance, a first inductance, and a second inductance. The push-pull pair of transistors includes first and second transistors. The first transistor includes control and output terminals. The second transistor includes input and control terminals. The control terminals of the first and second transistors collectively receive a differential input signal. The output and input terminals collectively provide a differential output signal. The capacitance is connected to the output and input terminals. The first capacitance cancels first harmonics at the output terminal of the first transistor with second harmonics at the input terminal of the second transistor. The first transistor and the first inductance are connected in series between a voltage source and a reference terminal. The second transistor and the second inductance are connected in series between the voltage source and the reference terminal. | 07-24-2014 |
20140232463 | CLASS RESONANT-H ELECTROSURGICAL GENERATORS - A generator for use with an electrosurgical device is provided. The generator has a gain stage electrically disposed between a first voltage rail and a second voltage rail, wherein the gain stage includes an input and an output. A voltage source operably coupled to the gain stage input and configured to provide an input signal thereto responsive to a drive control signal is also provided. The generator also has one or more sensors configured to sense an operational parameter of the amplifier and to provide a sensor signal corresponding thereto and a controller adapted to receive the sensor signal(s) and in response thereto provide a drive control signal to the voltage source. The generator has an amplifier output configured to supply an output voltage corresponding to the first voltage rail and the second voltage rail when the output of the gain stage falls between a voltage of the first voltage rail and a voltage of the second voltage rail and is configured to supply a peak voltage output when the voltage output is falls greater than the voltage of the first voltage rail or less than the voltage of the second voltage rail. | 08-21-2014 |
20140266443 | HIGH-FREQUENCY, BROADBAND AMPLIFIER CIRCUIT - According to one embodiment, a high-frequency, broadband amplifier circuit includes two drive elements, a matching circuit, a Balun circuit, a power supply, and a power supply circuit. The matching circuit includes two pattern circuits. The pattern circuits convey, in differential mode, the high-frequency signals supplied from the two drive elements. The Balun circuit converts the high-frequency signal to a single-end mode signal. The power supply circuit is connected one of the pattern circuits, and supplies at least the output of the power supply to the other pattern circuit. | 09-18-2014 |
20140361833 | SINGLE-INPUT CLASS-AB RAIL-TO-RAIL OUTPUT STAGE - An amplifier with a single-input class-AB output stage comprises an input stage providing a signal to an output stage. The output stage comprises a current-splitting stage having a bias current and providing at least two intermediate output currents, and a drive stage receiving the two intermediate output currents and driving an output signal having a positive side and a negative side. | 12-11-2014 |
20140368270 | MARCHAND BALUN AND POWER AMPLIFIER USING THE SAME - A Marchand balun has a primary transmission line with a width smaller than the two secondary transmission lines. The two secondary transmission lines also have different widths and lengths. This arrangement provides an imbalance between the widths and lengths of the transmission lines. It has been found that this imbalance can enable improved amplitude unbalance and phase unbalance. | 12-18-2014 |
20140368271 | AMPLIFIER CIRCUIT WITH OVERSHOOT SUPPRESSION - An amplifier circuit with overshoot suppress scheme including an input amplifier, an output amplifier, and a diode is provided. A first and a second input ends of the output amplifier are coupled to an output of the input amplifier. The diode is coupled between an output end and the first input end of the output amplifier. When the voltage difference between the output and the input ends of the output amplifier is greater then the barrier voltage of the diode, the diode is turned on, so that the output end of the output amplifier is coupled to the input end of the output amplifier. In the transient state, it rapidly smoothes the overshoot signal. In the steady state, the diode is cut off to maintain the normal operation of the operational amplifier. | 12-18-2014 |
20150028953 | Scalable Periphery for Digital Power Control - A scalable periphery digital power control arrangement is presented. The scalable periphery digital power control arrangement comprises a plurality of PMOS transistors connected in parallel, where the plurality of transistors is operatively coupled to a voltage source. The plurality of PMOS transistors that is operatively coupled to the voltage source can operate as a controlled current source. Current flow from the voltage source can be controlled by a logic circuit, which sends a logic signal to enable or disable each individual PMOS transistor of the plurality of PMOS transistors connected in parallel. As more PMOS transistors are enabled, the current flow through the scalable periphery digital power control arrangement to the amplifier can increase. | 01-29-2015 |
20150084694 | BUFFER CIRCUIT HAVING AN ENHANCED SLEW-RATE AND SOURCE DRIVING CIRCUIT INCLUDING THE SAME - A buffer circuit is provided. The buffer circuit includes an operational amplifier and a slew-rate compensating circuit. The operational amplifier amplifies an input voltage signal and generates an output voltage signal. The slew-rate compensating circuit generates a compensation current based on a voltage difference between the input voltage signal and the output voltage signal, and provides the compensation current to a load stage of the operational amplifier. | 03-26-2015 |
20150091646 | CURRENT MODE CLASS AB LOW-NOISE AMPLIFIER AND METHOD OF ACTIVE CABLE TERMINATION - This invention relates to medical ultrasonic imaging systems and, in particular, phased array imaging systems operating in different scan formats and imaging modalities. More specifically, the invention relates to the front-end processing of ultrasonic echoes. | 04-02-2015 |
20160134238 | Class AB Amplifier With Programmable Quiescent Current - A Class AB amplifier has a control stage and a push-pull stage. The control stage has a programmable resistor that allows a floating constant voltage to applied to the push-pull stage such that the quiescent current of the amplifier is relatively low. The configuration enables the amplifier to operate properly at relatively low power-supply voltage levels. The amplifier can be configured as the output driver for an operational amplifier (op-amp) with a Miller compensation configuration that replaces the conventional Miller compensation resistor with a transistor that is part of the op-amp. | 05-12-2016 |
20190149108 | Power-on-Reset and Phase Comparator for Chopper Amplifiers | 05-16-2019 |