26 results about "Operational transconductance amplifier" patented technology

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 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 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 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.

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.

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.

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.

A transmitter circuit with ringing suppression applicable to a controller area network bus is provided, which includes a CAN bus driver stage receiving a transmit data signal and generating a CAN high voltage signal and a CAN low voltage signal, a first operational transconductance amplifier electrically connected with the CAN bus driver stage for receiving the CAN high voltage signal, and a second operational transconductance amplifier electrically connected with the CAN bus driver stage for receiving the CAN low voltage signal. A common mode voltage of a dominant state as well as a control signal are applied such that when the control signal is logically high, the first and second operational transconductance amplifiers actively pulls the CAN high voltage signal and the CAN low voltage signal to be equal to the common mode voltage of the dominant state so as to suppress ringing phenomenon occurring in the CAN bus.

A voltage control circuit includes an operational transconductance amplifier circuit including a floating current source that is configured to receive a power voltage and is further configured to output a first current and a second current based on a difference between input voltage signals, a voltage conversion circuit including a first transistor that is configured to receive the first current and a second transistor that is configured to receive an input voltage, the second transistor being further configured to output a first voltage based on the first transistor being electrically connected to the power voltage, and a voltage output circuit including a third transistor electrically connected to the second transistor by a common input node and a fourth transistor configured to receive the second current, in which the common input node is configured to receive the first output voltage and the third transistor is configured to receive the input voltage.

The device comprises an operation transconductance amplification module and a capacitor, the forward input end of the operation transconductance amplification module is connected to the input end of the device, the output end of the operation transconductance amplification module is connected with the reverse input end of the operation transconductance amplification module, and the capacitor is connected with the reverse input end of the operation transconductance amplification module. The output end of the operational transconductance amplification module is connected with the first end of the capacitor to form a first node, the second end of the capacitor is grounded, and the first node is connected to the output end of the device and used for receiving an input signal; and the operational transconductance amplification module is used for amplifying the input signal according to the target gain current and eliminating input imbalance of a differential signal formed between the input signal and the amplified input signal at the same time, and a capacitor is used for filtering the gain signal output by the operational transconductance amplification module to output a target signal. The device can be integrated, the area of the filtering device is effectively reduced, and the device can be applied to applications with ultra-low-pass filtering requirements.

The invention discloses a controllable resistor module linearly changing along with current and application of the controllable resistor module. A controllable resistor comprises an operational transconductance amplifier, a PMOS (P-channel Metal Oxide Semiconductor) tube PM1 and a PMOS tube PM2, the controllable resistor module can generate an equivalent resistor in direct proportion to a sampling current, so that the equivalent controllable resistor Rds and the Isense can be linearly correlated, the influence of process errors and temperature is small, the generated error is small, and the controllable resistor module can be applied to current-controlled oscillators, automatic gain control and other scenes needing controllable resistors.

Control circuits, integrated circuits, electronic converters and methods are disclosed. In a control circuit for a switching stage of an electronic converter, a phase detector generates a drive signal in response to a phase difference between a first clock signal and a second clock signal. The first clock signal and the second clock signal are generated by a first current-controlled oscillator and a second current-controlled oscillator, respectively. An operational transconductance amplifier generates first and second control currents in response to a difference between a reference and a feedback of the electronic converter, the first and second currents being applied to control the first and second current-controlled oscillators. In response to a switching clock having a first state, a switching circuit applies first and second bias currents to control inputs of the first and second current-controlled oscillators, respectively. Conversely, in response to the switching clock having a second state, the switching circuit applies the second and first bias currents to the control inputs of the first and second current-controlled oscillators, respectively.

Described herein is an operational transconductance amplifier (OTA). The OTA includes two input pairs of transistors: a first pair provides a variable current based on a feedback voltage and an input voltage, and a second pair also absorbs the variable current based on the feedback voltage and the input voltage. The folded cascode arrangement includes two branches, one of which includes a Monicelli cell. A class AB output stage exists, and the input of the class AB output stage is connected to the two ends of the Monicheri unit. Further, the bias stage mirrors and scales the constant current to generate the control voltage. Within the folded cascode branches, the compensation transistors are controlled by these control voltages to ensure that the magnitudes of various variable currents provided and absorbed are equal, making the OTA independent of the input voltage.