42 results about "Operational transconductance amplifier" patented technology

The invention provides a multi-mode adaptive switching power supply, and relates to the technical field of electronic switches. The operational transconductance amplifier extracts a ripple voltage amplitude in the load voltage, compares the ripple voltage amplitude with a fixed reference voltage, and converts the ripple voltage amplitude into a proportional analog compensation current. The analog-to-digital converter quantizes the signal into a digital increment, and after the digital increment is superposed with a digital target signal output by the controller through the digital accumulator, a digital control code containing a real-time ripple compensation amount is generated. And the digital-to-analog converter is used for driving the switch tube to adjust the conduction time by comparing the dynamic comparator with the load voltage in real time according to the dynamic adjustment reference voltage. Real-time quantitative analysis and dynamic compensation of the ripple amplitude are realized, and accumulation of low-frequency ripple components is avoided. Meanwhile, the superposition logic of the digital accumulator enables the compensation amount to be continuously adjusted along with ripples, solves the problem of lagging of related threshold comparison, can quickly respond to load changes especially in a high-frequency switching scene, and improves the response precision and stability of a power supply to a transient load.

A system includes an analog-to-digital converter (ADC), a current source, and a controller. The ADC includes a comparator having a first input and a second input, and the current source includes an operational transconductance amplifier. The controller is configured to configure the operational transconductance amplifier with a first set of conductances; and use the current source to set a DC voltage at the first input. The controller is further configured to reconfigure the amplifier with a second set of conductances; and enable the comparator and use the current source to create a voltage ramp at the second input.

Systems, devices, and methods are described to provide an improved current mirror operational transconductance amplifier (OTA). Improved OTAs may include an input circuit arranged to receive a differential voltage input, a load circuit arranged to measure a positive branch current and negative branch current from the input circuit, a bias circuit arranged to determine a bias voltage based on the negative branch current, a folded current branch circuit arranged to generate an adaptive bias current and a pass transistor configured to adjust an amount of the adaptive bias current based on the bias voltage, and a push-pull output circuit configured to sink current based on the adjusted adaptive bias current. The folded current branch circuit may generate the adaptive bias current based on the measured negative branch current. The output circuit may source current based on the measured positive branch current. Advantageously, most transistors may be of minimum size.

According to an embodiment, a biasing circuit includes a high impedance bias stage coupled to sensor pads connected to a resistive sensor for detecting fly height in a hard disk drive. The circuit employs dual operational transconductance amplifiers with different bandwidths working in conjunction with switching circuitry to establish and maintain bias conditions. A first operational transconductance amplifier with a higher bandwidth provides fast initial settling, while a second operational transconductance amplifier with a lower bandwidth optimizes continuous operation. The architecture supports multiple operating modes, including differential voltage, differential current, and common mode configurations, through various arrangements of transistors, compensation capacitors, and feedback paths.

The present disclosure relates to error amplifier circuits for DC-DC converters, DC-DC converters and controllers. An error amplifier circuit for a DC-DC power converter controller for providing an amplified error signal to a switching control circuit is disclosed, the circuit comprising an error amplifier first stage. The first stage comprises: a first input for receiving a voltage proportional to an output voltage of the converter; an output node; a first operational transconductance amplifier in a first path between the input and the output node and having a first input connected to the input, a second input connectable to a reference signal and an output connected to the output node; and a second parallel path comprising a series combination of an amplifier, a second OTA and a capacitor. The second OTA has an output connected to the capacitor, a first input connected to an output of the amplifier and a second input connected to the output. Associated control circuits, controllers and converters are also disclosed.

A circuit optimization method and system for a digital domain correction of a temperature sensor is provided. The method includes: subjecting negative temperature coefficient voltages Vbep and Vben to a switch timing control, thereby generating a corresponding negative temperature coefficient voltage Vbep and positive temperature coefficient voltage Dvbe as inputs into an operational transconductance amplifier (OTA) that serves as a core circuit of a Sigam-Delt analog-to-digital converter (ADC); and generating, by a switch sampling circuit, Vintx by integrating; inputting the Vintx into a comparator (CMP) to acquire a final ADC output; and sending a feedback through a digital domain to an analog domain control switch logic. The circuit optimization method intelligently finds the optimal temperature factor of different processes through the digital domain correction, thereby acquiring the desired ratio value more accurately. Meanwhile, the circuit optimization method reduces the trim circuit to be implemented in the analog domain.

A preamplifier includes an operational transconductance amplifier, a first-type metal-oxide-semiconductor (MOS) transistor have a gate electrically coupled to the OTA output; a first second-type MOS transistor; a second second-type MOS transistor electrically connected in parallel with the first second-type MOS transistor; a first load resistor electrically connected in series with a drain of the first second-type MOS transistor that has a first output voltage; a second load resistor electrically connected in series with a drain of the second second-type MOS transistor that has a second output voltage; a tail node electrically connected to a source of the first second-type MOS transistor, a source of the second second-type MOS transistor, and a drain of a third second-type MOS transistor; a common-mode feedback circuit electrically coupled to the first and second output voltages and to a first OTA input; and a reference voltage electrically coupled to a second OTA input.

The invention discloses a fluidic resistor module based on LDO zero pole tracking compensation. The fluidic resistor module comprises an operational transconductance amplifier, a PMOS transistor PM1 and a PMOS transistor PM2. The in-phase end of the operational transconductance amplifier is connected with the drain electrode of the PMOS transistor PM1, and the anti-phase end of the operational transconductance amplifier is connected with a first ideal voltage source; the output end G12 of the operational transconductance amplifier is connected with the grid electrode of the PMOS tube PM1 and the grid electrode of the PMOS tube PM2 at the same time; the drain electrode of the PMOS transistor PM1 is connected with an ideal current source Isense; the source electrode of the PMOS transistor PM1 and the drain electrode of the PMOS transistor PM2 are connected with an ideal voltage source VCC at the same time; a source electrode S2 of the PMOS transistor PM2 is connected with a capacitor C1, and the other end of the capacitor C1 is connected with a second ideal voltage source. The fluidic resistor module can generate an equivalent resistor inversely proportional to a sampling current, so that the equivalent fluidic resistor Rds can be linearly correlated with 1 / Isense, and the problems that a traditional fluidic resistor module cannot linearly change along with the 1 / Isense and the control is inaccurate are solved; meanwhile, the influence of process errors and temperature on the fluidic resistor is small, and generated errors are small.

The application belongs to the technical field of analog integrated circuits, and particularly relates to a high-efficiency swing rate enhanced full-differential operational transconductance amplifier. The circuit of the application comprises an input signal following circuit, an alternating current signal coupling circuit and an operational transconductance amplifier main circuit. The input signal following circuit effectively reduces the output impedance by adding local negative feedback, and ensures effective following of the input signal under the condition that the load current changes greatly. The alternating current signal coupling circuit adopts a complementary gate-source short MOS tube structure, ensures high impedance under the condition that the internal node swing is large, thereby realizing good alternating current coupling characteristics, and improving current utilization rate and small signal performance. The operational transconductance amplifier main circuit adopts a following circuit to expand the signal amplitude between the input tube gate and source, and under the condition of a large signal, the current-voltage conversion ratio is improved to 4 times of that of the traditional structure, and is no longer limited by the fixed tail current.

An output buffer for a source driver of a panel includes an output stage for outputting an output voltage, an operational transconductance amplifier for controlling the output stage to charge or discharge a panel pixel capacitance, and a detector coupled between the operational transconductance amplifier and the output stage for outputting an enable signal to turn on or turn off the output buffer after the output buffer finishes charging or discharging the panel pixel capacitance, wherein the enable signal is determined according to an output current of the output stage. The output buffer can be turned off after the panel pixel capacitance finishes charging or discharging, thereby reducing the power consumption of the display driver.

The invention discloses a high-precision fast transient response low dropout linear regulator which comprises a DC loop and an AC loop, the DC loop comprises a regulator tube device MP, an error operation transconductance amplifier gm, DC, a compensation circuit, an intermediate drive circuit-A and a feedback resistor, and the AC loop comprises a voltage detection circuit and a second operation transconductance amplifier gm, AC; the regulator tube device MP is connected between a power supply input end and a power supply output end and receives a DC output signal from the error operation transconductance amplifier gm, and the DC output signal is controlled by the intermediate stage driving circuit-A; in conclusion, the defects in the prior art are overcome, the design is reasonable, the stability margin and the transient response speed are improved by using the dual-loop control mode of the DC loop and the AC loop, and the high social use value and the application prospect are achieved.

A circuit arrangement is provided which includes an array of stages for photon counting current to voltage conversion. Each stage includes a tunable operational transconductance amplifier and a feedback network forming a feedback loop of the operational transconductance amplifier. Each stage is configured to provide an output signal as a function of an input signal that is provided to the amplifier input of the operational transconductance amplifier, wherein the input signal comprises one or more current pulses and the output signal comprises one or more voltage pulses. With the tunable operational transconductance amplifier the transconductance of a stage can be tuned so that differences in peaking time and gain are avoided. Furthermore, an imaging device and a method for operating a circuit arrangement are provided.

A low dropout regulator comprising: a supply voltage connection for receiving a supply voltage; a load voltage output connection for providing a load voltage to a load; load voltage output control circuitry comprising a pass transistor configured to regulate the load voltage based on a voltage at its gate region; adaptive biasing circuitry comprising: a biasing transistor configured to regulate the voltage provided to the gate region of the pass transistor based on a voltage provided to a gate region of the biasing transistor; and operational transconductance amplifier, OTA, circuitry comprising a first OTA transistor and a second OTA transistor, wherein a gate region of the first OTA transistor is arranged to receive a reference voltage and a gate region of the second OTA transistor is arranged to receive a voltage indicative of the load voltage; and adaptive compensation circuitry comprising: (i) a first compensation capacitor having a first electrode and a second electrode, (ii) a second compensation capacitor having a first electrode and a second electrode, and (iii) a first compensation transistor, wherein the second electrode of the first compensation capacitor is coupled to a first region of the first compensation transistor, and wherein the first electrode of the second compensation capacitor is coupled to both a second and a gate region of the first compensation transistor; wherein a first region of the second OTA transistor is coupled to: (i) the supply voltage connection, (ii) the first electrode of the first compensation capacitor, and (iii) the gate region of the biasing transistor; and wherein a second electrode of the second compensation capacitor is coupled to a first region of the biasing transistor.

The present application relates to a kind of multiple transconductance amplifier, characterized in that, including operational transconductance amplifier, first threshold control device, second threshold control device, threshold control device includes current source, for output threshold current;Input end, for obtaining the first current of operational transconductance amplifier output;Current processing device, for comparing the numerical value of threshold current and first current, when first current is greater than threshold current, after the operation of threshold current and first current, output adjustment current;Total output end, first current and adjustment current, after the operation of output total current.The present application provides a kind of multiple transconductance implementation, can be according to the change of output voltage, judge whether the output current exceeds the set threshold, if exceeding threshold, then automatically adjust output current, so that the transconductance value of the overall circuit changes.

The invention relates to an operational transconductance amplifier. The improved OTA may include an input circuit arranged to receive a differential voltage input; a load circuit arranged to measure a positive branch current and a negative branch current from the input circuit; a bias circuit arranged to determine a bias voltage based on the negative branch current; a folded current branch circuit arranged to generate an adaptive bias current; and a pass transistor configured to adjust an amount of the adaptive bias current based on the bias voltage; and a push-pull output circuit configured to draw a current based on the adjusted adaptive bias current. The folded current branch circuit may generate an adaptive bias current based on the measured negative branch current. An output circuit may supply a current based on the measured positive branch current. Advantageously, most transistors may have a minimum size.

A method for jointly receiving a differential input signal in a pipeline ADC having a first and a second ADC input terminal, the method comprising: a) providing an operational transconductance amplifier (OTA) having a differential input and a differential output and a first quantizer terminal; b) for each ADC input port: 1) Providing multiple input signal sampling capacitors (C S <0:3>), a first feedback capacitor (Cf), wherein a second lead of the feedback capacitor (Cf) is connected to second lead wires of the input signal sampling capacitors (C S <0:3>); 2) coupling a first lead of the feedback capacitor (Cf) to a first voltage, coupling the second lead of the input signal sampling capacitors (C S<0:3>) with a second common-mode voltage, and coupling first leads of the input signal sampling capacitors (C S <0:3>) to each of the ADC input terminals; 3) Decoupling the first connecting wires of the input signal sampling capacitors (C S <0:3>) from the respective ADC input terminals and decoupling the second connecting wires of the input signal sampling capacitors (C S <0:3>) from the second common mode voltage; 4) Coupling the second leads of the input signal sampling capacitors (C S <0:3>) to a respective one of the differential inputs of the OTA and coupling a respective output of the OTA to the first leads of the input signal sampling capacitors (C S <0:3>) and with an input to a first quantizer; c) locking an output of the first quantizer; and d) for each ADC input port: 1) Coupling the first lead of the first feedback capacitor (Cf) to the output of the OTA, and coupling the first lead of each of the input signal sampling capacitors (C S <0:3>) with a positive or a negative voltage in response to the output latched in the first quantizer.

A front-end electronic circuitry for an electromagnetic radiation sensor application comprises a charge sensitive amplifier stage with a first single-input operational transconductance amplifier, and a transistor being arranged in a first feedback path of the first single-input operational transconductance amplifier, and a signal shaper stage with a second single-input operational transconductance amplifier, and an active feedback circuit being arranged in a second feedback path of the second single-input operational transconductance amplifier. The front-end electronic circuitry further comprises a control circuit having a second transistor. The control circuit is configured to provide a control signal to control the transistor of the first feedback path in dependence on a gate-source voltage of the second transistor.

Certain aspects of the present disclosure generally relate to electronic circuits, and more particularly to an operational transconductance amplifier (OTA). One example amplifier generally includes: a first pair of input transistors (214, 216); a first pair of cascode transistors (210, 212) coupled in cascade with the first pair of input transistors (214, 216), respectively; a second pair of input transistors (222, 224); a second pair of cascode transistors (218, 220) coupled in cascade with a second pair of input transistors (222, 224), respectively; and a third pair of input transistors (226, 228) coupled to the second pair of cascode transistors (218, 220), respectively.

This invention discloses an easily integrated all-MOS structure memristor analog circuit, which consists of two functional modules: a current-multiplexed integrator module and an operational transconductance amplifier module. M1-M3 constitute the current-multiplexed integrator module, used to convert the input voltage to the integration control voltage and memorize the historical state of the input voltage signal; M1 and M2 form a current-multiplexed structure, and M3 acts as a MOS transistor capacitor to achieve the integration function. M4-M8 constitute the operational transconductance amplifier module, used to realize the resistive-change memory characteristic of the memristor analog circuit; M4 and M5 form a completely symmetrical current mirror structure, M6 and M7 are differential input pairs with identical structure and parameters, and M8 serves as a tail current source. This invention features a simple circuit structure that is easy to integrate, consisting of only eight MOS transistors, eliminating the need for discrete components such as operational amplifiers and multipliers, and meeting the requirements for miniaturization, low power consumption, and wide bandwidth.

The invention discloses a full-integration low-dropout linear regulator circuit with a fast transient response function. The full-integration low-dropout linear regulator circuit structurally comprises an error amplifier circuit, a buffer circuit, a transient enhancement circuit, a voltage sampling circuit, a power PMOS (P-channel Metal Oxide Semiconductor) transistor and an output capacitor. The method comprises the following steps that: the transient enhancement circuit detects transient fluctuation of output voltage through a coupling capacitor, amplifies charging and discharging current by utilizing a current mirror structure, and quickly adjusts grid voltage of a power PMOS (P-channel Metal Oxide Semiconductor) transistor, so that overshoot and undershoot of the output voltage when load current jumps are remarkably reduced, and recovery time is shortened; the stability of the loop is guaranteed by adopting a mode of combining a single-stage operational transconductance amplifier with a Miller compensation capacitor; a push-pull structure buffer is used to enhance the driving capability. According to the embodiment of the invention, a novel transient enhancement circuit is adopted, the system complexity is reduced, the transient response speed of the low-dropout linear regulator is improved, and the low-dropout linear regulator can be widely applied to the technical field of integrated circuits.

A signal generation circuit comprising a first chopper, an operational transconductance amplifier, a second chopper and a ripple reduction loop circuit. The operational transconductance amplifier is coupled to receive a differential input signal, and the differential input signal is processed into an output signal at an output node by the operational transconductance amplifier and the second chopper. The ripple reduction loop circuit is coupled between the output node and a compensation node of the operational transconductance amplifier. The ripple reduction loop circuit comprises a third chopper and an operational amplifier. The third chopper is configured to convert a ripple in the output signal into a direct current offset signal. The operational amplifier is configured to convert the direct current offset signal into a compensation signal. The compensation signal is configured to input to the compensation node of the current mirror circuit.

The application discloses a mobile phone screen controllable low-power consumption display debugging circuit and method in the technical field of mobile phone screens, which comprises an input signal adjusting module, a temperature compensation module and a signal correction module, the signal correction module comprises an analog multiplier U, an impedance matching module and a feedback circuit, the output end of the analog multiplier U is electrically connected with the input end of the impedance matching module, the output end of the impedance matching module is electrically connected with the feedback circuit, the output end of the feedback circuit is electrically connected with the input end of an RC low-pass filter, and the output end of the RC low-pass filter is electrically connected with the input end of a signal conversion module. The application adjusts the output electric signal through a second operational transconductance amplifier, carries out multiplication operation through an analog multiplier to offset the output drift characteristics of a digital-to-analog converter, thereby eliminating color deviation and display distortion, realizes frequency modulation by multiplying the input electric signal with a feedback signal, suppresses high-frequency noise and reduces the risk of screen display distortion.

The invention discloses an ultra-low power consumption body-driven four-stage differential operation transconductance amplifier, which belongs to the technical field of CMOS (Complementary Metal Oxide Semiconductor) analog integrated circuits, and comprises a biasing circuit, a body-driven differential input circuit, a composite differential amplification circuit, a frequency compensation circuit and a common-mode feedback circuit. The bias circuit provides stable bias under the ultra-low voltage of 0.3 V; the body-driven differential input circuit takes a PMOS tube body end as a differential signal input end, and improves equivalent transconductance in combination with a cross positive feedback structure; the composite differential amplification circuit realizes signal multi-stage amplification and rail-to-rail output through a two-stage differential common-source amplification unit and a feedforward AB type output unit; the frequency compensation circuit optimizes the frequency stability in a mode of combining a Miller capacitor and an RC (Resistance-Capacitance) compensation network; and the common-mode feedback circuit stably outputs a common-mode level. The amplifier is suitable for ultra-low power consumption application scenes such as implantable medical electronics and wearable equipment.

The application discloses a flow control resistance module based on LDO zero-pole tracking compensation, which comprises an operational transconductance amplifier, a PMOS tube PM1 and a PMOS tube PM2; the noninverting terminal of the operational transconductance amplifier is connected with the drain of the PMOS tube PM1, and the inverting terminal is connected with a first ideal voltage source; the output terminal G1_2 of the operational transconductance amplifier is connected with the gate of the PMOS tube PM1 and the gate of the PMOS tube PM2; the drain of the PMOS tube PM1 is connected with an ideal current source Isense; the source of the PMOS tube PM1 and the drain of the PMOS tube PM2 are connected with an ideal voltage source VCC; the source S2 of the PMOS tube PM2 is connected with a capacitor C1, and the other end of the capacitor C1 is connected with a second ideal voltage source. The flow control resistance module can generate an equivalent resistance which is inversely proportional to a sampling current, can make the equivalent flow control resistance R ds be linearly related to 1 / I Isense , solves the problem that a traditional flow control resistance module cannot follow the linear change of 1 / I sense , and the control is not accurate; meanwhile, the flow control resistance is less affected by process errors and temperature, and the generated error is small.

A low-dropout voltage regulator includes: a power supply voltage connection point; a load voltage output connection point; a load voltage output control circuit including a pass transistor; an adaptive bias circuit including a bias transistor; and an operational transconductance amplifier (OTA) circuit including a first OTA transistor and a second OTA transistor; and an adaptive compensation circuit including: (i) a first compensation capacitor, (ii) a second compensation capacitor, and (iii) a first compensation transistor, wherein a second electrode of the first compensation capacitor is coupled to a first region of the first compensation transistor, a first electrode of the second compensation capacitor is coupled to a second region and a gate region of the first compensation transistor, and a first region of the second OTA transistor is coupled to: (i) the power supply voltage connection point, (ii) the first electrode of the first compensation capacitor, and (iii) the gate region of the bias transistor. The second electrode of the second compensation capacitor is coupled to the first region of the bias transistor.

An amplifier circuit includes an amplifier core having a cascode transistor and a gain transistor, a bias circuit coupled to the amplifier core, the bias circuit comprising: a first current source, a second current source, an operational transconductance amplifier (OTA), a bias cascode transistor pair having a bias cascode transistor and a bias gain transistor, and a replica circuit coupled to the first current source and to the second current source.

This disclosure relates to a low-power integrator for a continuous-time ΔΣ analog-to-digital converter (ADC). The integrator includes: a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh switch, an eighth switch, an operational transconductance amplifier, a first capacitor, a second capacitor, and a third capacitor. In this embodiment, the integrator controls the opening and closing of the first to eighth switches to alternately utilize either the first or second capacitor. The integrated charge accumulated by the input current over a certain time period is directly "poured" onto the third capacitor of the integrator. Integration is achieved through charge sharing between the first or second capacitor and the third capacitor. This eliminates the need for the operational transconductance amplifier to provide a large current to charge the integrating capacitor, reducing the requirement for high-performance active devices and lowering the integrator's power consumption, thereby contributing to a reduction in the power consumption of the continuous-time ΔΣ ADC.

The invention discloses a debugging circuit and method for controllable low-power-consumption display of a mobile phone screen in the technical field of mobile phone screens, and the debugging circuit comprises an input signal adjustment module, a temperature compensation module and a signal correction module which comprises an analog multiplier U, an impedance matching module and a feedback circuit. The output end of the analog multiplier U is electrically connected with the input end of the impedance matching module, the output end of the impedance matching module is electrically connected with the feedback circuit, the output end of the feedback circuit is electrically connected with the input end of the RC low-pass filter, and the output end of the RC low-pass filter is electrically connected with the input end of the signal conversion module. An output electric signal is adjusted through the second operational transconductance amplifier, the output drift characteristic of the digital-to-analog converter is counteracted through multiplication of the analog multiplier, so that color deviation and display distortion are eliminated, frequency modulation is achieved by multiplying the input electric signal with a feedback signal, high-frequency noise is restrained, and the display quality is improved. And the risk of screen display distortion is reduced.

A voltage differential current feed transconductance amplifier system (VDCCTA), consisting of: a voltage differential current booster module (VDCC); an operational transconductance amplifier (OTA) module, combined with the VDCC module on a Z-connector; and a variety of connections, including: two input connections; five output connections; and two buffered connections, wherein the two input connections are configured to receive differential input voltages, one output connection is configured to provide current output, two output connections are configured to provide current images of the connection providing current output, and two further output connections are configured to provide transconductance outputs; the system is configured to be tunable by pre-flows; and the system is further configured to operate as an active inductor simulator when connected to a grounded capacitor.

A system includes an analog-to-digital converter (ADC), a current source, and a controller. The ADC includes a comparator having a first input and a second input, and the current source includes an operational transconductance amplifier. The controller is configured to configure the operational transconductance amplifier with a first set of conductances; and use the current source to set a DC voltage at the first input. The controller is further configured to reconfigure the amplifier with a second set of conductances; and enable the comparator and use the current source to create a voltage ramp at the second input.