90 results about "Negative feedback amplifier" patented technology

A distance image sensor for removing the background light and improving the charge transfer efficiency in a device for measuring the distance to an object by measuring the time-of-flight of the light. In a distance image sensor for determining the signals of two charge storage nodes which depend on the delay time of the modulated light, a signal by the background light is received from the third charge storage node or the two charge storage nodes in a period when the modulated light does not exist, and is subtracted from the signal which depends on the delay time of the two charge storage nodes, so as to remove the influence of the background. Also by using a buried diode as a photo-detector, and using an MOS gate as gate means, the charge transfer efficiency improves. The charge transfer efficiency is also improved by using a negative feedback amplifier where a capacitor is disposed between the input and output.

An imaging device for sensing an image of an object includes a negative feedback amplifier, a substrate, a sense electrode, a couple electrode and an insulation protection layer. The sense and couple electrodes are disposed above the substrate. The insulation protection layer covers the sense and couple electrodes. The sense electrode and the object form a sense capacitor. The couple electrode and the object form a couple capacitor. A negative input terminal of the negative feedback amplifier is electrically connected to the sense electrode, and the couple electrode is electrically connected to a signal output terminal of the negative feedback amplifier and a signal input terminal of the imaging device.

A feedback controller comprises first and second feedback circuits. The first feedback circuit is connected between an input node and an output node and has an error node. The first feedback circuit comprising a feedback amplifier for comparing a feedback signal to a reference signal and providing an error signal, and a comparator for comparing the error signal to a second reference signal and providing an output signal. The second feedback circuit is connected between the input node and the error node and comprises a current source coupled to the error node and a controller coupled to the input node for controlling the current source in response to a value of the feedback signal being above or below a threshold value.

The variable gain amplifier includes a bias circuit (BC) 1, a matching circuit (MC) 2, a variable gain resistive feedback amplifier (FA) 3 and an output follower (EA) 4. The resistance values of the load resistance Rc and feedback resistance Rf are changed in cooperation. In a case of making the load resistance Rc a high resistance to set the low noise amplifier to a high gain, the feedback resistance Rf is also made a high resistance, the feedback time constant τfb(c1)≈2π·RfCbe/(1+gmRc) of the closed loop of the resistive negative feedback amplifier 3 becomes substantially constant, and then the amplifier has a gain small in frequency dependency over a wide bandwidth. In a case of making the load resistance Rc a low resistance to set the low noise amplifier to a low gain, the feedback resistance Rf is also made a low resistance. The feedback resistance Rf with the low resistance increases the negative feedback quantity, and thus the amplifier is set to a low gain. Also, the load resistance Rc is made a low resistance, and the feedback time constant τfb(c1) becomes substantially constant. The gain is not lowered further in a high frequency region.

A negative feedback amplifier which alleviates reduction in band width and effectively protects an amplifier from electrostatic discharge (ESD). A node is provided at the midpoint of a feedback resistor connected between an output terminal and an input terminal of an amplifier. Each of ESD protective diodes are connected between the node and respective power terminals. ESD threshold voltage and band width vary in accordance with the resistance of a resistor between the input terminal and the node. Setting the resistance of the resistor at 10 to 100Ω makes it possible to secure the necessary ESD threshold voltage while hardly reducing band width.

The invention discloses an analog input circuit for engineering-machinery-dedicated controller. The analog input circuit comprises a voltage-current transformation circuit, which is a current series negative feedback amplifier circuit, and an analog voltage input circuit, which includes orderly connected a first RC filter circuit having an input thereof connected with a current output of said voltage-current transformation circuit, a noninverting amplifying circuit, and an isolating circuit having an output thereof connected with an A/D sampling port of a control unit. The analog resistor input circuit of the invention has the characteristics of strong anti-interference capability, high reliability, good compatibility, flexible applicability, and convenient operation, is also adaptable to wretched field environment and applied to the control circuit of engineering machinery equipment.

A negative feedback amplifier for a transmitter, in which a vector corrector outputs the corrected signals, an adder adds the feedback signals of the in-phase component and the quadrature component to the in-phase component and the quadrature component of the output of the vector corrector, respectively, a modulator performs a quadrature modulation with respect to the in-phase component and the quadrature component of the outputs from the adder, a power amplifier amplifies the output of the modulator, a demodulator performs a quadrature demodulation to a part of the output of the power amplifier and outputs the feedback signals of the in-phase component and the quadrature component, and the vector corrector performs a correcting operation of canceling an error of at least one of the phases and the amplitudes of the in-phase component and the quadrature component occurring in the demodulator.

The invention relates to a module parallel type high power direct current switch power device which comprises a plurality of direct current switch power modules which are parallel and a plurality of outer ring negative feedback modules of total output current and voltage after being parallel. One of the direct current switch power modules is internally provided with a current negative feedback inner ring control loop, and one of the outer ring negative feedback modules is internally provided with a total output current negative feedback outer loop and a total output voltage outer ring loop. The invention eliminates the master-slave installation operation of the prior master-slave installation method parallel power device, thereby causing the use to become simple, saving components and lowering the cost. At the same time, the device is added with the total output current negative feedback outer ring loop to cause the total output current after being parallel to also get negative feedback control, thereby greatly enhancing the output stability of the device.

The photocurrent monitoring circuit (PMC) includes non-linear sampling circuit, negative feedback amplifier, sampling mirror image circuit, current mirror, and I/V switching circuit etc. The non-linear sampling circuit consists of transistor Q1 and resistance R2. The negative feedback amplifier is composed of amplifier A2 and field effect tube M8. The sampling mirror image circuit is composed of transistor Q2 and resistance R3. Current mirror, and I/V switching circuit include field effect tubes M4, M5, M6, M7 and resistance R4. Being able to monitor the input photocurrent in large dynamic range, PMC still keeps high precision. When PMC monitors the input photocurrent in large dynamic range, normal operation of main body of magnifier is not influenced.

The invention relates to an image sensing device which is used for sensing an image of an object. The image sensing device at least comprises a negative feedback amplifier, a substrate, a sensing electrode, a coupling electrode and an insulation protection layer, wherein the sensing electrode and the coupling electrode are arranged above the substrate; the insulation protection layer covers the sensing electrode and the coupling electrode; the sensing electrode and the object form a sensing capacitor; the coupling electrode and the object form a coupling capacitor; a negative input end of the negative feedback amplifier is electrically connected with the sensing electrode; and the coupling electrode is electrically connected to a signal output end of the negative feedback amplifier or a signal input end of the image sensing device.

In a double-loop negative feedback low noise amplifier having double negative feedback paths by a feedback transformer and a feedback resistor added to a cascode amplifier comprising transistors and a resistor, a phase compensation circuit comprising a capacitor and a resistor is added between the output terminal of the double-loop negative feedback low noise amplifier and the input terminal of the cascode amplifier, i.e., the input terminal of the input transistor, and a phase compensation circuit comprising a capacitor and a resistor is added to the upper-stage transistor of the cascode amplifier, i.e., the input terminal of the upper-stage transistor. Those phase compensation circuits enable a low noise negative feedback amplifier which maintains a high feedback loop gain to a high frequency band, has a wider bandwidth than a conventional one, and has a high dynamic range.

The present invention provides a semiconductor integrated circuit device equipped with a negative feedback amplifier circuit or a step-down circuit which realizes stabilization of an output voltage effectively in response to a variation in power supply voltage. A constant current source is used to cause a bias current for setting current consumption to flow in a differential amplifying MOSFET. A capacitor is provided between an external power supply voltage and a predetermined circuit node to thereby detect a reduction in the external power supply voltage. An operating current of the differential amplifying MOSFET is increased through the use of a current flowing in the capacitor due to such an external power variation, thereby executing the operation of stabilizing an output voltage corresponding to the reduction in the external power supply voltage.

A feedback amplifier having an improved feedback network including two cross coupled switches that isolate the amplifier from extraneous undesired electrical signals present in a system or network when the amplifier is turned off (i.e., in an off-state). The cross coupled switches interconnect two feedback paths of a feedback network to enable out-of-phase differential signals to be summed and effectively canceled. Further, the feedback amplifier provides on-stage advantages to enable different amplifier characteristics and parameter to be selectively engaged by turning on or turning off certain feedback networks.

A method for double sampling loop negative feedback comprising: obtaining a low-frequency feedback signal from the output of the amplifier; obtaining a high-frequency feedback signal from part of the amplifier of which high-frequency phase shift is low, wherein two-ways sampling signals have the same amplifying phase; combining the two-ways sampling signals together using a series capacitor-inductor double signal combining circuit to form one signal, the signal having low phase shift at both high and low-frequency and being used for negative loop feedback. The invention also provides a double negative feedback amplifier using the method.

The invention discloses a high precision portable electrochemical detection terminal. In the prior art, the conventional electrochemical detector has the disadvantages of complicated structure, bad interference resistant performance, bade stability, and low detection precision, and the provided detection terminal solves the problems mentioned above. The detection terminal is characterized by comprising a forward voltage follower circuit, a RE electrode and CE electrode based on the forward voltage follower circuit, a current/voltage conversion circuit, a WE electrode based on the current/voltage conversion circuit, and a three-circle opposite vertex intersected negative feedback amplifier, which is connected to the current/voltage conversion circuit. The provided detection terminal has the advantages of simple circuit, good circuit stability, strong interference resistant property, low energy consumption, and high testing precision, and thus is suitable for promotion and application.

To satisfy a specified frequency band over a wide range by regulating the phase characteristics of an input signal using an operational amplifier arranged differently from a feedback amplifier at an error amplifier section, and to prevent oscillation while having a sufficient phase margin in the frequency characteristics of an open loop. An error amplifier section 32 for amplifying the input signal of the entire circuit depending on a feedback signal from an output current voltage converting section 34 for voltage converting the output current of the entire circuit is provided with a voltage control/current output type operational amplifier 6 having a transfer conductance gm and outputs a current of an amplified input signal. The operational amplifier 6 has a constant current source and the characteristics of a differential amplification circuit based on the transfer conductance gm. Consequently, a phase regulation circuit corresponding to the operational amplifier 6 comprises a resistor R31 and a capacitor C31 being connected in series between the output terminal of the operational amplifier 6 and the earth potential.