568 results about "Error amplifier" patented technology

The invention is suitable for the technical field of LED backlight driving, and provides a starting control circuit for LED backlight driving, a chip and a display device. The starting control circuit of the LED backlight drive comprises a detection selection module, an error amplification module, a first change-over switch module, a control module, a second change-over switch module, a logic drive module, a feedback module and a first switch module. When each first voltage is in a preset range, the first change-over switch module is used for conducting the first input end of the error amplification module and the output end of the error amplification module. And the second change-over switch module is used for transmitting the overcurrent protection signal to the logic driving module. When the detection voltage is larger than the first reference voltage, the first change-over switch module is used for conducting the first input end of the error amplifier and the detection selection module. And the second change-over switch module is used for conducting the control module and the logic driving module. Therefore, the Boost has more response time to respond to the rapid change of the LED.

The invention provides a voltage stability control method for a multi-output switching power supply, which comprises the following steps of: sampling a main output channel in real time to obtain a voltage signal; the voltage signal is processed through a wide bandwidth error amplifier, a main channel adjusting signal is generated, and the main channel adjusting signal is used for driving a main power switch device; receiving an input voltage fluctuation frequency band of an auxiliary channel, a load current transient change gradient and a frequency spectrum coupling characteristic of a main channel adjusting signal through a dynamic prediction model, and generating an auxiliary channel adjusting signal with a phase lead compensation characteristic; a cross coupling active offset mechanism is constructed, time domain-frequency domain characteristics of coupling interference are extracted through a high-precision differential detection circuit, amplitude-frequency adjustable reverse correction signals are generated in real time through an adaptive compensation algorithm and injected into control nodes of an auxiliary output channel, and dynamic decoupling and ripple suppression are carried out. According to the method, high-stability control of multi-channel voltage under all working conditions is realized, and the dynamic response speed and the anti-interference capability are improved.

A DC / DC converter includes a converter stage to receive an input voltage and to provide an output voltage from the input voltage in accordance with a modulated drive signal. The converter stage further provides a feedback voltage representing the output voltage. A controller circuit includes an error amplifier to receive the feedback voltage and a reference voltage and to provide an error signal based on the feedback voltage and the reference voltage. A PWM modulator receives a clock signal and the error signal and generates a modulated signal based on the clock signal and the error signal, and a logic circuit receives the modulated signal and generates the drive signal for the converter stage based on the modulated signal so that the drive signal has the same duty cycle as the modulated signal, when the duty cycle of the modulated signal is not smaller than a minimum duty cycle value.

The invention relates to the technical field of chip detection, and discloses a high-reliability power supply chip circuit fault detection system, which comprises a built-in self-test architecture integrated in a low dropout regulator chip, and the built-in self-test architecture is provided with a first test mode and a second test mode which are switched based on a mode switching control circuit. The detection module is used for detecting key performance parameters of an error amplifier sub-circuit in a low dropout linear regulator chip, the detection module is used for measuring the direct current loop gain, the offset voltage, the common mode rejection ratio and the power supply ripple rejection ratio of the amplifier in the first test mode, and the detection module is used for measuring the unity gain bandwidth of the amplifier in the second test mode. According to the invention, through the design of a built-in self-test architecture and two test modes, abnormal states such as differential circuit imbalance and feedback loop fault can be identified in a bare chip stage, chips with poor performance are rejected in advance, and the LDO chip is ensured to reach a ppb-magnitude high reliability standard.

The invention belongs to the technical field of electronic circuits, and provides a negative voltage charge pump circuit, a switching power supply converter and electronic equipment. A reference voltage generation module, a comparison module, a fourth driving module, a fifth power tube, a sixth power tube and a seventh power tube are additionally arranged on an existing charge pump. The reference voltage generation module is used for generating third reference voltage, namely threshold voltage when the negative-voltage charge pump circuit enters the light load, then the comparison module is used for comparing the third reference voltage with error voltage output by the error amplifier, and whether the negative-voltage charge pump circuit enters the light-load working condition or not is judged; when the negative-voltage charge pump circuit enters a light-load working condition, the large-size power tube and the driving module thereof are closed, and only the small-size power tube works, so that other performances of the negative-voltage charge pump circuit are ensured, the working current of the negative-voltage charge pump circuit in the light-load state is greatly reduced, and the working efficiency of the negative-voltage charge pump circuit is improved. Therefore, the conversion efficiency of the charge pump circuit in light load is improved.

An error amplifier includes a first transistor having a first error amplifier input and having first and second current terminals, a second transistor having a second error amplifier input and having third and fourth current terminals, a first resistor coupled between a supply voltage terminal and the first current terminal, and a second resistor coupled between the supply voltage terminal and the third current terminal. The error amplifier has a second stage circuit coupled to the first and second resistors. The second stage circuit has an error amplifier output. The second stage circuit is configured to cause less current to flow through the second stage circuit than a current that flows through either of the first or second resistors or the first or second transistors.

The invention discloses an LDO (Low Dropout Regulator) circuit based on a level conversion and pre-adjustment module. The LDO circuit comprises a reference source, an error amplifier, a pre-adjustment module, a level conversion module, a power switch tube P1, a power circuit tube N1 and resistance feedback networks R1 and R2. The pre-adjustment module carries out voltage reduction processing on an input high-voltage power supply, and the level conversion module generates bias voltage according to an enable signal and the high-voltage power supply, controls a power switch and a switch in the operational amplifier, and ensures that the circuit is resistant to high voltage and extremely low in drain. The error amplifier adjusts the grid voltage of the power circuit according to the feedback and reference voltage difference value, and controls the current to stably output the voltage. And the resistance feedback network realizes closed-loop regulation of the output voltage. Under the condition that the LDO is enabled to be closed, the power tube can be ensured to be completely closed no matter the LDO is under the working voltage of 3V or 5V, so that the electric leakage condition of the LDO is greatly improved, and the LDO has the characteristic of low electric leakage.

The invention provides an output negative voltage protection circuit applied to an N-type power device linear voltage regulator. The output negative voltage protection circuit comprises a voltage comparator, a current comparator, an error amplifier, a buffer driver, a power device MP, a resistor R1, a resistor R2, a resistor Rload and a capacitor Cout. The method comprises the following steps: acquiring a voltage difference between an S-pole output voltage Vout of a power device MP and a reference voltage Vos through a voltage comparator, converting the voltage difference into a current signal Ieg, and comparing the current signal Ieg with a reference current Ios through a current comparator to generate a current signal Ilim; adjusting the output of an error amplifier according to the current signal Ilim, and dynamically adjusting the G pole voltage Vgate of the power device MP; when the output voltage Vout is lower than the reference voltage Vos, the G pole voltage Vgate is pulled down to turn off the power device MP through the current signal Ilim, and protection of the power device MP is achieved.

The utility model discloses a constant-current and constant-voltage circuit without software control, which comprises a Buck power level circuit, a voltage sampling circuit, a current sampling circuit and an error amplifying circuit, and the error amplifying circuit is provided with a first error amplifier and a second error amplifier. The output end of the first error amplifier and the output end of the second error amplifier are electrically connected with the Buck power level circuit, the Buck power level circuit is electrically connected with the voltage sampling circuit and the current sampling circuit, the voltage sampling circuit is electrically connected with the first error amplifier, and the current sampling circuit is electrically connected with the second error amplifier. An FREQ pin of a Buck chip U4 is grounded, a 0.76 V voltage is obtained through voltage division by a resistor R27 and a resistor R29, so that the switching frequency of a Buck power level circuit is invalid, the voltage is controlled through a first error amplifier, the current is controlled through a second error amplifier, the first error amplifier and the second error amplifier carry out operation, and then a PWM comparator in the Buck chip U4 is controlled through a COMP pin of the Buck chip U4. Therefore, voltage and current are controlled.

The invention provides a transimpedance type flip voltage following driving linear voltage regulator, which comprises a control module and a transimpedance type flip voltage follower, namely a TIFVF module, and is characterized in that the control module comprises an error amplifier and a voltage-current converter which are connected in series; the output voltage Vout passes through a selectable divider resistor and then is fed back to an error amplifier to be compared with the reference voltage Vref to obtain an error signal, the error signal is amplified and conditioned by a compensation network to obtain a control voltage signal Vctrl, and the control voltage signal Vctrl passes through a voltage-current conversion circuit to obtain a current control signal Ictrl required by the TIFVF; the whole forms a negative feedback loop, and two links of error amplifier-voltage and current conversion provide enough loop gain.

The invention provides a feedback compensation circuit for a switching power supply. The feedback compensation circuit comprises a reference voltage source, an error amplifier, a feedback capacitor, a sampling circuit, an optocoupler output circuit and a PWM control chip, output voltage is connected to the inverted input end of the error amplifier through the sampling circuit, the reference voltage source is connected to the in-phase input end of the error amplifier, and the output end of the error amplifier is connected to a feedback pin of the PWM control chip through the optocoupler output circuit. The sampling circuit comprises an upper sampling resistor, a lower sampling resistor, a second resistor and a second capacitor; the feedback capacitor is connected between the inverting input end and the output end of the error amplifier; by selecting feedback capacitors with different capacities, the low-frequency gain of a transfer function from output to control of the feedback compensation circuit is adjusted. According to the invention, the element parameter design process is greatly simplified, the controllability of low-frequency gain is enhanced, and the technical effects of easy parameter design and simple debugging are achieved.

The invention relates to the technical field of power management, in particular to a two-way switching LDO framework suitable for an MCU sleep mode. Comprising a main LDO, an auxiliary LDO and a current detection circuit. The main LDO comprises a second error amplifier and a second adjusting tube; the auxiliary LDO comprises a first error amplifier and a first adjusting tube; the main LDO and the auxiliary LDO share the same voltage feedback network, and the voltage reference and the feedback output of the voltage feedback network are connected with the input end of the first error amplifier and the input end of the second error amplifier at the same time. The outputs of the first adjusting tube and the second adjusting tube are short-circuited and then are output to the MCU, and are simultaneously input to the input end of the voltage feedback network; the input end of the current detection circuit is connected with the output end of the first error amplifier, and the output end is connected with the current switch of the second error amplifier. The architecture provided by the invention meets the requirements of low power consumption and quick response of the MCU, and the power consumption of the architecture is not influenced by the power consumption of the MCU.

In described examples, an integrated circuit (IC) includes an error amplifier, first and second resistors, first and second transistors, and a current source. A control terminal of the first transistor is coupled to an output of the error amplifier. A first terminal of the second transistor is coupled to a first terminal of the first transistor and a first terminal of the first resistor. A control terminal of the second transistor is coupled to a second terminal of the first resistor, a second terminal of the second resistor, and a first input of the error amplifier. A first terminal of the current source is coupled to a second terminal of the second transistor.

The invention provides an error amplifier for peak current mode control and a converter system. The error amplifier comprises a transconductance amplifier, a voltage clamping module, a voltage-current converter, a slope compensation module, a current clamping module and a mirror image tube, the negative end of the transconductance amplifier is used for loading feedback voltage, and the positive end is used for loading reference voltage; the output end of the transconductance amplifier, the output end of the voltage clamping module and the input end of the voltage-current converter are electrically connected; the voltage-current converter generates error current; the slope compensation module is used for performing slope compensation on the error current to generate a compensated current; the output end of the slope compensation module, the output end of the current clamping module and the positive end of the high-side comparator are electrically connected with a second reference node; and the mirror image tube is used for loading the comparison voltage to the positive end of the high-side comparator. The error amplifier provided by the invention can realize more stable mode switching and more accurate current limiting control.

The present invention discloses an LDO circuit with soft start and foldback current limiting protection functions, including a bandgap reference module, a soft start module, a voltage selection module, a current limiting protection module, a first error amplifier, an output power tube, a first voltage divider resistor, and a second voltage divider resistor; the present invention realizes that there is no overshoot when the LDO is powered on, and the power consumption of the chip after entering the foldback current limiting is greatly reduced, thereby ensuring the safety of the chip. By reusing the control signal of the soft start circuit, the problem of failure to start with a constant current load in the traditional foldback protection circuit is solved, and the ability to power on with a load is improved. At the same time, it can be easily adjusted by V SET The voltage can flexibly adjust the current limit value at power-on according to the load requirements, providing good protection for the chip while meeting the application requirements.

To provide a controller in which total harmonic distortion (THD) can be improved.SOLUTION: A controller (700) includes: a first external terminal receiving a first voltage (Vmult) with a full-wave rectified waveform; a second external terminal receiving a first detection voltage (Vis), as a negative voltage, generated by a current flowing through a sense resistor (Ris) connected to a ground potential application terminal; an error amplifier circuit (710) generating a second voltage (V2) by amplifying an error between a second detection voltage (Vs) corresponding to an output voltage (Vdc) and a reference voltage (Vref1); an arithmetic circuit (733) generating a third voltage (V4) by multiplying the first and second voltages; an inverting amplifier (734) generating a fourth voltage (V5) by inverting and amplifying the first detection voltage; and a comparator (735) comparing the third voltage and the fourth voltage.SELECTED DRAWING: Figure 11

The invention discloses a clamping circuit of an error amplifier, which belongs to the field of analog integrated circuits and comprises an error amplifier EA, a low-voltage clamping circuit and a high-voltage clamping circuit. The error amplifier EA comprises a first-stage operational amplifier, the non-inverting input end of the first-stage operational amplifier is connected with feedback voltage VFB, the inverting input end of the first-stage operational amplifier is connected with reference voltage VREF, and the first-stage operational amplifier outputs VC voltage; the error amplifier EA is used for amplifying the change of the feedback voltage VFB; when the VFB is reduced or increased, the corresponding low-voltage clamping circuit or the high-voltage clamping circuit works, the output VC of the first-stage operational amplifier is clamped to the low-voltage clamping limit VclampL or the high-voltage clamping limit VclampH, the VC is controlled to be within a certain range, then clamping of the output current IEA of the error amplifier EA is achieved, quick response and stable adjustment of a loop are achieved, and meanwhile the function of protecting the circuit is achieved.

The invention discloses an LDO (Low Dropout Regulator) with a load transient response enhancement circuit and electronic equipment, and belongs to the technical field of integrated circuits. The circuit comprises an error amplifier, a buffer, a power tube, a feedback circuit, a compensation circuit and an LTRE module. The output end EAO of the error amplifier is connected with the grid electrode of the power tube through the buffer, the error amplifier compares reference voltage with feedback voltage, an EAO signal adjusts the conduction degree of the power tube, and the output voltage of the LDO is kept stable; the compensation circuit comprises an NMOS tube and a capacitor. The grid of the NMOS tube is connected with the input end of the buffer, the drain is connected with one end of the capacitor, and the source is grounded; the other end of the capacitor is connected with the EAO; one end of a delay circuit in the LTRE module is connected with the input end of the buffer, and the other end of the delay circuit is connected with the grid electrode of the NMOS tube, so that the grid electrode voltage is delayed to rise when the buffer voltage rises. The circuit has the advantages of low working voltage, low voltage drop and low static power consumption, and the transient response can be enhanced when the load current is increased or decreased.

A power supply control device, which is a main controller of a switching power supply, includes an error amplifier, a ramp signal generation circuit, a comparison signal generation circuit, a logic circuit, a switch drive circuit, a reverse current detection circuit, and a ramp signal holding circuit. The logic circuit adjusts an input offset of the comparison signal generation circuit, the error signal, or the ramp signal in a direction that reduces a difference between the error signal and the ramp signal in response to a predetermined trigger signal.

The invention discloses a low dropout linear regulator with bidirectional current conduction capability, which is characterized in that two input ends of an error amplifier are respectively connected with signals VB and FB, and a power level of a linear transconductance ring is used as a light load power level; the first output end of the error amplifier is connected with the first input end of the linear transconductance ring, the first input end of the light load power level and the input end of the first source follower, and the output end of the first source follower is connected with the first input end of the heavy load power level. The second output end of the error amplifier is connected with the second input end of the linear transconductance ring, the second input end of the light load power level and the input end of the second source follower, and the output end of the second source follower is connected with the second input end of the heavy load power level. The problem that the quiescent current of a traditional bidirectional current conduction LDO is too large under the conditions of light load and no load is solved, and it is guaranteed that the output power tube can be completely conducted when the LDO works in an open loop mode.

The invention discloses a seamless range switching system and a seamless range switching method for instrument current measurement. The seamless range switching system comprises a digital-to-analog converter, an error amplifier, a first driving circuit, a first current measurement circuit, a clamping circuit, a second driving circuit, a second current measurement circuit, two analog-to-digital converters and a field programmable gate array. The first current measuring circuit converts 10 [mu] A to 30 mA low current into a first voltage signal to form a negative feedback closed loop. When the first voltage signal reaches a Zener breakdown threshold value, the clamping circuit outputs a trigger signal to start the second driving circuit, so that the two driving circuits jointly provide a total current of 30mA to 500mA for the load; the two analog-to-digital converters perform synchronous sampling, and the field programmable gate array selects digital signal output which is in a linear measurement range and has an error not exceeding + / -0.05% of a full scale. No mechanical switch exists in the switching process, the current is uninterrupted, and wide-range high-precision continuous measurement is achieved.

Provided is a power source control device for a DC / DC converter including a high-side transistor, a low-side transistor, and an inductor, the power source control device including a first error amplifier configured to receive a first reference voltage and a feedback voltage based on an output voltage of the DC / DC converter, a second error amplifier configured to receive an output of the first error amplifier and a signal indicating information regarding a current flowing through the inductor, a first comparator configured to receive an output of the second error amplifier and a ramp voltage, a switching control unit configured to perform switching control of the high-side transistor and the low-side transistor according to an output of the first comparator, and a clamp circuit configured to clamp a second amplifier output voltage outputted from the second error amplifier, to a predetermined clamp voltage.

This invention discloses a power supply device, a thermal regulation method, and a power supply system. The power supply device includes a power switch for converting a first power signal into a second power signal according to a control signal; a first current source for providing a current signal to a first node; a control circuit for converting the current signal into the control signal; a temperature-controlled current extraction circuit including at least one temperature sensing element disposed at at least one position on the power switch for generating at least one voltage signal, the at least one voltage signal being respectively related to the temperature of the at least one position; an error amplifier for generating an adjustment signal based on the at least one voltage signal and a reference voltage; and an adjustment switch for extracting an adjustment current from the current signal at the first node according to the adjustment signal.

The invention relates to the technical field of integrated circuit design, high-voltage power supply management chips and the like, and provides a voltage stabilizing circuit suitable for a high-voltage power supply management chip and the high-voltage power supply management chip. The circuit comprises an error amplifier, an N-channel MOS tube M1 and a voltage setting feedback network. The error amplifier outputs a control signal to the grid electrode of the M1 by comparing a reference voltage with a feedback voltage; the drain electrode of the M1 is connected with input high voltage VIN, and the source electrode is grounded through a feedback network to form a negative feedback structure. The voltage stabilizing circuit provided by the invention is simple in structure, high in stability and fast in response, can solve the problems of complex loop gain and difficult compensation, realizes the simplification of a loop structure, improves the phase margin of a circuit system, enhances the stability and load transient response, can be integrated in a high-voltage power supply management chip, and has a wide application prospect. And a stable low-voltage power supply is provided for high-voltage applications such as industry and automotive electronics.

The application discloses a kind of LDO without slice outside capacitance, belongs to linear power supply technical field, including transconductance constant circuit Gmc, constant transconductance error amplifier AE1, first output circuit, error amplifier AE2, second output circuit, band gap reference circuit BGR, power tube Pn1 and power tube Pn2;The transconductance constant circuit Gmc is used to generate bias voltage signal;The constant transconductance error amplifier AE1 is used to generate first output signal;The error amplifier AE2 is used to generate second output signal;Band gap reference circuit BGR generates multiple independent stable outputs, provides stable reference voltage for constant transconductance error amplifier AE1 and error amplifier AE2, and then generates bias voltage through transconductance constant circuit Gmc, and constant transconductance error amplifier AE1 drives power tube Pn1 through first output circuit to output signal for analog load, and error amplifier AE2 drives power tube PN2 through second output circuit to output signal for digital load.

The application discloses a kind of self-adaptive power energy storage converter control method and system, this method can effectively solve the problem of overvoltage and under-voltage of grid-connected point and overcharge and overdischarge of energy storage battery by controlling the adaptive charge and discharge of energy storage battery.First, the grid voltage is sampled and the effective value is processed to obtain the grid voltage effective value feedback signal U gf_rms , and it is sent to the inverting input end of voltage error amplifier, and the grid voltage reference U ref Is sent to the non-inverting input end of voltage error amplifier.The output U e Of voltage error amplifier is obtained by positive and negative limiting link U e1 Is sent to one input end of multiplier.The state signal J of range determination is obtained by the state of charge signal Soc of energy storage battery, and the other input end of multiplier is sent.The output I ref Of multiplier is sent to the non-inverting input end and inverting input end of current regulator respectively with the charging current sampling signal I bf Of energy storage battery.The output of current regulator is used as modulation signal, and it is sent to PWM modulator.

A reference buffer with wide output voltage and current range is provided. A reference buffer includes an error amplifier comprising a first input, a second input, and a first output, wherein the amplifier is configured to generate an output signal indicative of an error between an output reference signal and an internal reference signal. The reference buffer further includes a first voltage follower circuit configured to generate the output reference signal based, at least in part, on the output signal of the error amplifier, wherein the first voltage follower comprises a third input and a second output, and wherein the second output is coupled to the second input of the error amplifier.

The invention relates to a BOOT converter soft start circuit for a large-area-array image sensor, and belongs to the technical field of power management. The technical problem of output voltage overshoot caused by overlarge difference between reference voltage and feedback voltage when the BOOST converter is started is mainly solved. According to the technical scheme, a soft start module generates a linearly-increased soft start voltage VSS, and when the VSS is smaller than a reference voltage VREF, the VREF is replaced to be input into an error amplifier, so that a feedback voltage VFB linearly rises along with the VSS, and the surge of an inductive current is restrained. Technical effects include thoroughly eliminating voltage overshoot, maintaining optimal performance parameters of the system, providing programmable startup characteristics, enhancing system reliability, and simplifying integration complexity.

The application discloses a kind of static current control systems of double data rate linear voltage regulator, including reference generating circuit and by feedback control circuit, error amplifier circuit and power output circuit constitute idle power consumption control circuit, reference voltage VREF generated by reference generating circuit is exported to feedback control circuit, after feedback control circuit compares the control signal output by error amplifier circuit, exports to error amplifier circuit to make the control signal output by error amplifier circuit also change, the control signal in turn controls upper and lower power tube in power output circuit, by adjusting VREF generated by reference generating circuit, to flexibly adjust system idle power consumption, while considering low power consumption and the fast transient response of load switching.

The present disclosure relates to a switching converter and its control circuit. The control circuit includes an error amplifier, a transient-response compensation circuit and a PWM comparator. The transient-response compensation circuit is coupled to an output terminal of the error amplifier for increasing a differential current of the error amplifier to increase the rate of output change of the error amplifier in a case that a voltage difference between the first feedback signal and the reference voltage exceeds a predetermined threshold. The output voltage can be prevented from having too high or too low fluctuations when a load changes, thereby improving transient response characteristics of the power converter, and optimizing dynamic characteristics of the power converter over a wide range of the fluctuation of the load in a continuous operation mode.