| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 330258000 | Having common mode rejection circuit | 25 |
| 20130082778 | DIFFERENTIAL AMPLIFIER - In an embodiment are provided are a differential amplifier, a method of amplifying a differential input signal, a device including a differential amplifier, and a low voltage differential signaling receiver. | 04-04-2013 |
| 20090045876 | LOW NOISE, LOW POWER, HIGH LINEARITY DIFFERENTIAL AMPLIFIER WITH A CAPACITIVE INPUT IMPEDANCE - A low noise, low power differential two-stage amplifier includes a first stage comprising a pair of electrical devices that sense an input signal difference across the pair of electrical devices; and a control feedback loop operatively connected to the first stage, wherein the first stage in combination with the control loop feedback is adapted to place an exact copy of the signal across a first pair of resistive components, wherein the first pair of resistive components are adapted to generate a differential signal current, wherein the control feedback loop is adapted to ensure that the differential signal current goes a second pair of resistive components to generate a voltage output. Preferably, the first and second pair of resistive components are in ratio to produce the exact copy of the signal with some gain at an output of the first stage. | 02-19-2009 |
| 20090267693 | RESISTOR SELF-TRIM CIRCUIT FOR INCREASED PERFORMANCE - In a method and apparatus for trimming values of load resistors to reduce variations there between, a common mode feedback loop (CMFBL) included in a differential amplifier is switched from operating in a closed loop mode to operate in an open loop mode. The CMFBL includes an operational amplifier (OA) generating an output signal. A selector switch, coupled to receive the output signal, is operable to switch a path of the output signal in response to a CAL signal. In the closed loop mode, the selector switch routes the output signal to a feedback loop to provide a regulated current to the load resistors. In the open loop mode, the OA operates as a comparator and the output signal is provided as a digital signal. The selector switch provides the digital signal to a controller to digitally trim the values of the load resistors. | 10-29-2009 |
| 20090009248 | INPUT BUFFER WITH OPTIMAL BIASING AND METHOD THEREOF - A method and circuit of a biased input buffer is described to maximize the quality in the output signals. The input buffer includes a first stage for receiving differential input signals and generating differential internal signals as biased in response to an averaging of the differential internal signals. The input buffer further includes a second stage coupled to the differential internal signals and configured to generate differential output signals. A memory device includes a memory array with the respective input buffer. Differential input signals are received and differential internal signals are generated as biased in response to an averaging of the differential internal signals. Differential output signals are generated in a second stage from the differential internal signals. | 01-08-2009 |
| 20090009247 | DIFFERENTIAL AMPLIFIER AND SAMPLING AND HOLDING CIRCUIT - Disclosed is a differential amplifier including: first and second transistors each having a first gate, a second gate, a source, and a drain open to a drain side, the first gate and the second gate being controlled independently, a differential input being supplied to between the first gates of the first and second transistors, and the sources of the first and second transistors being connected in common to a first reference potential; first and second load circuits each connected to each of drain sides of the first and second transistors; a detection circuit detecting a common-mode voltage between ones of drain sides of the first and second transistors; and a comparison and amplification circuit amplifying the common-mode voltage in comparison with a second reference potential and supplying an output signal thereof to both of the second gates of the first and second transistors. | 01-08-2009 |
| 20080224776 | COMMON-MODE VOLTAGE CONTROLLER - A common-mode voltage controller for adjusting common-mode voltages between a first buffer and a second buffer at a subsequent stage or a preceding stage of the first buffer in a signal transmission circuit, comprising: a first reference voltage generation unit for generating a common-mode voltage corresponding to the first buffer; a second reference voltage generation unit for generating a common-mode voltage corresponding to the second buffer at the subsequent stage or the preceding stage; and a control signal generation unit for generating a control signal for controlling a common-mode voltage of the first buffer according to a difference voltage between an output of the first reference voltage generation unit and an output of the second reference voltage generation unit, and giving the control signal to the first buffer and first reference voltage generation unit. | 09-18-2008 |
| 20080284513 | FULLY DIFFERENTIAL AMPLIFIER - A fully differential amplifier includes: an N-stage amplifier including first to Nth amplifier stages, where N is a positive integer greater than or equal to 2, the first to Nth amplifier stages being cascaded in sequence so as to generate a pair of differential output voltages; a common mode feedback circuit coupled to the N-stage amplifier, detecting a common mode level of the differential output voltages, and controlling the first amplifier stage according to the common mode level detected thereby; and a common mode frequency compensation circuit including a pair of capacitors, each having a first terminal coupled to the N-stage amplifier to receive a respective one of the differential output voltages, and a second terminal coupled to a common mode node of the first to (N-1)th amplifier stages of the N-stage amplifier. | 11-20-2008 |
| 20090251216 | Common mode control circuitry for multi-stage operational amplifiers - This disclosure relates to a common mode regulation in multi stage differential amplifiers. | 10-08-2009 |
| 20090085662 | Common mode voltage extraction circuit - Consistent with the present invention, there is provided a circuit for extracting a common mode voltage of an input signal. The device may include an operational amplifier having an output, at least one negative input and at least one positive input, a first transistor, and a second transistor. A terminal of the first transistor may be coupled to the output of the operational amplifier. A terminal of the second transistor may be coupled to a terminal of the first transistor and the at least one positive input of the operational amplifier to create a negative feedback loop. The device may further include a common mode output, wherein the negative feedback loop extracts the common mode voltage of the input signal, the common mode voltage of the input signal being output at the common mode output. The device consistent with the present invention may provide the common mode voltage of the input signal without using any resistors, and while only occupying a small die area. | 04-02-2009 |
| 20090108936 | Combination trim and CMFB circuit and method for differential amplifiers - A differential amplifier ( | 04-30-2009 |
| 20090212865 | Differential Audio Amplifier - A differential audio amplification apparatus with common mode rejection is shown, having a first input current path ( | 08-27-2009 |
| 20090115521 | High CMR amplifier topology - An amplifier topology includes an input stage comprising a differential pair which conducts respective output currents in response to a differential input signal. Bias current sources provide the pair's tail current and respective bias currents for the input stage in response to a drive voltage. After flowing through the input stage, most or all of the input stage bias currents are summed at a summing node, the summed currents being a current I | 05-07-2009 |
| 20080231365 | OPERATIONAL AMPLIFIER - An operational amplifier including an input amplifier configured to amplify at least one differential input signal, a first common mode feedback amplifier configured to amplify a first common mode voltage, a cascode amplifier configured to cascode-amplify output signals from the input amplifier and the first common mode feedback amplifier, a first common mode voltage generator configured to generate a central voltage of the output signal from the cascode amplifier and input the central voltage to the first common mode feedback amplifier, and a frequency compensator configured to feedback the output signal of the cascode amplifier to the first common mode feedback amplifier so as to compensate a frequency of the first common mode feedback amplifier. | 09-25-2008 |
| 20090066417 | High bandwidth apparatus and method for generating differential signals - An apparatus and method for generating differential signals. The apparatus includes a first operational amplifier receiving a first signal, a second operational amplifier receiving a second signal, and a first transistor. The first transistor includes a first gate, a first terminal, and a second terminal. Additionally, the apparatus includes a second transistor. The second transistor includes a second gate, a third terminal, and a fourth terminal. Moreover, the apparatus includes a first resistor coupled to the first terminal and the third terminal, and a second resistor coupled to the second terminal and the fourth terminal. Also, the apparatus includes a first current supplier coupled to the first terminal, a second current supplier coupled to the second terminal, a third current supplier coupled to the third terminal, and a fourth current supplier coupled to the fourth terminal. | 03-12-2009 |
| 20110025419 | DIFFERENTIAL AMPLIFIER WITH OFFSET VOLTAGE TRIMMING - A differential amplifier that has a current supply and a differential current to voltage converter with a positive current input node, a negative current input node and a voltage output node, has offset voltage trimming. The voltage output node provides an output voltage that is proportional to the difference in current values flowing into the positive current input node and a negative current input node. A trimming circuit has a plurality of trimming control inputs, an inverting trimming output, a non-inverting trimming output and trimming inputs coupled to the current supply. Trimming resistances couple the inverting trimming output to the non-inverting trimming output. Trimming selectors, controllable by a trim code provided to the trimming control inputs, provide for selectively connecting the current supply directly to the non-inverting trimming output while selectively connecting the current supply to the inverting trimming output through a first selected group of the trimming resistances. The differential amplifier also has a differential transistor pair formed by an inverting transistor that couples the inverting trimming output to the positive current input node and a non-inverting transistor that couples the non-inverting trimming output to the negative current input node. | 02-03-2011 |
| 20090051433 | DIFFERENTIAL SENSING WITH HIGH COMMON MODE REJECTION - A differential operation circuit that uses the differential input signals to generate a reference voltage that fluctuates with the common mode voltage of the differential input signals. The reference voltage includes a common mode component that generally follows the common mode voltage of the differential input signals. The common mode component of the reference voltage is used to fully or almost fully offset the common mode voltage of the differential input signals, thereby increasing the differential operation circuit's common mode rejection characteristics. | 02-26-2009 |
| 20080218266 | Amplifier circuit with input terminals thereof connected to sampling capacitors - Sampling capacitors are connected respectively to a pair of differential input terminals of an operational amplifier. The sampling capacitors sample input signals. Source terminals and drain terminals of dummy switches are connected respectively to paths connecting the operational amplifier and the sampling capacitors, so that a common-mode voltage of differential input voltages to the operational amplifier is adjusted by gate-channel capacitances. | 09-11-2008 |
| 20080315951 | CLASS AB DIFFERENTIAL AMPLIFIER WITH OUTPUT STAGE COMMON MODE FEEDBACK - A differential amplifier includes an output stage, a first common mode feedback circuit; and a current source. The output stage includes first and second complimentary output terminals. The first common mode feedback circuit is operable to determine an average voltage across the first and second complimentary output terminals. The current source is coupled to the output stage, and the common mode feedback circuit is operable to control the current source based on the average voltage. A method includes determining an average voltage across a positive output terminal and a negative output terminal of a differential amplifier output stage and controlling current injected into the output stage based on the average voltage. | 12-25-2008 |
| 20080204138 | FULLY DIFFERENTIAL AMPLIFIER WITH CONTINUOUS-TIME OFFSET REDUCTION - A fully differential amplifier circuit according to one embodiment includes a first section for generating first and second output signals on first and second outputs from first and second input signals; a first feedback loop coupled to the first section, the first feedback loop including a second section for adjusting the first output signal towards a common mode voltage level, and for reducing an offset voltage of the first output signal; a second feedback loop coupled to the first section, the second feedback loop including a third section for adjusting the second output signal towards the common mode voltage level, and for reducing an offset voltage of the second output signal; and a filter section positioned on the first and second feedback loops between outputs of the second and third sections and the first section. | 08-28-2008 |
| 20090027125 | Common mode rejection calibration method for difference amplifiers - A common mode rejection calibration scheme for use with a difference amplifier having an associated signal path. A signal is generated which varies with the common mode voltage of the differential input voltage applied to the amplifier. This signal is scaled and coupled into the signal path such that the scaled signal reduces the common-mode error that would otherwise be present in the difference amplifier's output. | 01-29-2009 |
| 20120001691 | VARIABLE GAIN AMPLIFIER WITH REDUCED POWER CONSUMPTION - A variable gain amplifier includes a first common mode (CM) node configured to receive a first differential signal of a pair of differential signals. A first regulator couples to the first CM node, the first regulator being configured to generate a first CM offset. A second CM node is configured to receive a second differential signal of the pair of differential signals. A second regulator couples to the second CM node, the second regulator being configured to generate a second CM offset. In one embodiment, the first CM offset and the second CM offset together comprise a net CM offset, the net CM offset being configured to replace a current source net offset. | 01-05-2012 |
| 20090115522 | Low power, low noise amplifier system - A low power, low noise amplifier system includes at least one amplifier having first and second differential input terminals, first and second differential output terminals and providing a differential output; first and second input capacitors interconnected with the first and second differential amplifier input terminals; first and second feedback circuits containing first and second feedback capacitors, respectively, interconnected with the amplifier differential input and output terminals; an input chopper switch circuit for receiving a low frequency differential input and selectively, alternately swapping those low frequency differential inputs through the input capacitors to the differential input terminals of the amplifier; an output chopper switch for receiving and selectively, alternately swapping the amplifier differential outputs synchronously with the input chopper switch circuit; and a low pass filter responsive to the swapped differential outputs for providing a low noise, low power amplification of the low frequency differential inputs. | 05-07-2009 |
| 20090058526 | COMMON MODE FEEDBACK AMPLIFIER WITH SWITCHED DIFFERENTIAL CAPACITOR - A structure and related design structure for providing a common mode feedback to a differential amplifier are disclosed. A common mode feedback amplifier is connected to a differential amplifier to provide common mode feedback voltage thereto. An input of the common mode feedback amplifier is shorted to an output terminal of the differential amplifier during a sampling phase, and is coupled to the differential output voltage through two matched capacitors during a holding phase. | 03-05-2009 |
| 20090212864 | PREAMPLIFIER FOR RECEIVER AND METHOD THEREOF - A preamplifier used in a receiver is provided. The preamplifier comprises an input circuit and an output circuit. The input circuit receives an input differential voltage pair, pulls it down when the common voltage of the input differential voltage pair is higher than a reference voltage. The output circuit receives the input differential voltage pair outputted from the input circuit to pull high or low an output voltage accordingly. | 08-27-2009 |
| 20080297253 | Single-Ended Gain Stage And Disk Drive - An electrical apparatus comprising an amplifier having a first input, a second input, and an output. The apparatus further comprises a first electrical path coupled to the first input and having a first resistance and a first electrical path coupled to the second input and having a second resistance. The apparatus further comprises a second electrical path coupled to the second input and having a third resistance and a second electrical path, comprising an electrically-controllable resistance, coupled between the output and the first input. Further, the apparatus comprises circuitry for controlling the electrically-controllable resistance for adjusting a ratio between the electrically-controllable resistance and the third resistance to approximate a ratio between the first resistance and the second resistance. | 12-04-2008 |
