30 results about "Current sense amplifier" patented technology

A current sense amplifier measures a voltage drop in a drive transistor LS to measure the current flowing through the drive transistor LS. The current sense amplifier includes a preamplifier pre-amp, to which a voltage across the drive transistor LS is inputted, and which obtains a positive output and a negative output corresponding to a voltage difference of the inputted voltage across the drive transistor; and a switch sw, which connects the input end of a common mode voltage vcm and the negative output, the common mode voltage vcm serving as the operation reference of the preamplifier pre-amp. A change of the positive output caused by turning on / off the switch sw can be detected.

The invention discloses a current detection device with zero drift temperature compensation and nonlinear temperature compensation functions and a current detection method, the device comprises a shunt, a current detection amplifier, a first reference source, a second reference source, a temperature detection circuit and a microcontroller, the shunt is connected in series between a load and a power supply; the current detection amplifier is connected with two ends of the shunt and is used for amplifying an initial voltage signal generated by the shunt into U0; the microcontroller is connected with the current detection amplifier, and the first reference source and the second reference source respectively provide UA and UB for the current detection amplifier and the microcontroller; and the microcontroller is used for converting U0 into DADC, calculating T and calculating the detected current I according to a current calculation formula based on the DADC and the T, and the current calculation formula has temperature compensation coefficients related to the first reference source, the second reference source and the current detection amplifier. The device has the advantages that the device has enough measurement stability and accuracy in a full working temperature region.

An overcurrent protection integrated circuit includes: a current input including a first resistor receiving an input current; a current sense amplifier circuitry including a differential amplifier, a switching element, a second resistor, and a current mirror circuit; and an overcurrent determiner including a third resistor and an overcurrent protection comparator. The current sense amplifier circuitry controls, through the differential amplifier, a voltage of the second resistor to be equal to a voltage of the first resistor, and sends out, from the switching element toward the current mirror circuit, a current decreased to a predetermined ratio relative to the input current. The overcurrent determiner compares a voltage of the third resistor and a voltage of a direct-current power supply, and outputs a signal when the voltage of the third resistor exceeds the voltage of the direct-current power supply. The first resistor and the second resistor include the same metal material.

The invention provides a switch valve diagnosis circuit of relays. The switch valve diagnosis circuit comprises a relay K1, a relay K2, a relay K3, a relay K4, a sampling resistor, a load power supply, a current detection amplifier, an optocoupler 3, an optocoupler 4 and an MCU. The common end of the K1 is connected with the common end of the K2, and the normally-open end of the K1 and the normally-open end of the K2 are connected in parallel and then are connected in series with the common end of the K3 and the common end of the K4. The normally open end of the K3 and the normally open end of the K4 are connected with a load through a sampling resistor. The load power supply is connected with the sampling resistor. The current detection amplifier is used for detecting voltage difference between two ends of the sampling resistor. And the optocoupler 3 and the optocoupler 4 respectively receive a valve opening signal and a valve closing signal. The MCU is connected with the current detection amplifier and is used for determining the current value of the load loop according to the voltage difference. The MCU is further used for determining valve opening action time and valve closing action time according to the valve opening signal and the valve closing signal and determining state information of the valve according to the valve opening action time or the valve closing action time.

The invention discloses a single-power wide common-mode input current detection amplification circuit, and the circuit comprises a pre-attenuation resistance network which is used for attenuating a common-mode voltage on a differential signal according to a preset attenuation ratio K, and then inputting the attenuated common-mode voltage to an input end of a first operational amplifier; the first operational amplification module is used for amplifying the signal output by the front attenuation resistance network by G1 times and then outputting the amplified signal in a differential form; and the second operational amplification module is used for converting the differential output of the first operational amplification module into a single-ended output signal and providing G2 times of gain. According to the single-power-supply wide-common-mode-input current detection amplifying circuit, common-mode input voltage far exceeding working voltage can be input, and the application range of a current detection amplifier is widened to a great extent.

A resistive-type memory device comprises at least one memory array. Each memory array includes reference cells and a reference generator that generates a reference voltage that is midway between a first voltage and a second voltage, the first voltage being a function of a first current through a first reference cell, the second voltage being a function of a second current through a second reference cell, the first reference cell and the second reference cell being a pair of reference cells storing complementary values in a row of the memory array. The reference voltage is thus automatically centered and tracks the variation in a read current for all PVT corners without the need of tuning and adjustment of the reference voltage. This reference generator works with a current sense amplifier in certain implementation examples to reliably output the correct read data for all PVT corners.

Current sensing read amplifier (304; 403; 613) for use as a read amplifier in a memory arrangement of memory cell groups, wherein each of the cells (402; 720) of the memory cell groups contains at least one read terminal which is connected to a read amplifier by a bit line (102; 302; 405), and wherein the read amplifiers are connected to a data output, wherein the current sensing read amplifier comprises: a voltage regulator to maintain a bit line voltage at a constant voltage value below a power supply voltage and above ground; a measuring circuit for detecting a high current value and a low current value in an input signal; a generator for producing a high-voltage output signal when a high current input value is detected, and for producing a low-voltage output signal when a low current input value is detected; and Setting circuit for adjusting the independence of the measuring circuit from bit line leakage currents.

[Problem to be solved] The disclosure is to deal with a wide range of DC voltages in the input.[Solution] In a current sense amplifier 100, an upper side voltage and a lower side voltage of a current detection resistor 2 are input thereto, and an output corresponding to a difference between the upper side voltage and the lower side voltage is obtained. A common mode voltage suppressor 12 includes: voltage division resistors R6a and R6b, the upper side voltage and the lower side voltage being supplied to the two ends thereof, and a division voltage being obtained; a first transistor M1, the upper side voltage being input to one end thereof, and the other end thereof being connected to a predetermined power supply; and a second transistor M2, the lower side voltage being input to one end thereof, and the other end thereof being connected to a predetermined power supply. A control end of the first transistor M1 and a control end of the second transistor M2 are commonly connected and the division voltage is input thereto.

A voltage regulator feedback circuit includes a first comparator, a second comparator and a logic circuit. The first comparator is configured to generate an overshoot signal based on a comparison of a voltage regulation target signal to a feedback voltage signal. The second comparator is configured to generate a forward current signal based on a comparison of the current sense amplifier voltage to a reference voltage. The logic circuit is configured to generate a breaking signal based on the overshoot signal and the forward current signal. A gate signal of a transistor connected between a second end of the inductor and a reference ground is generated based at least in part on the breaking signal and is configured to cause the transistor to open based at least in part on the breaking signal having a true value.

Easily set the offset voltage of the post-amplifier. [Solution] The system includes a preamplifier 10 that obtains a preamplifier positive output vc and a preamplifier negative output vb according to the difference between the upper and lower voltages of a current sensing resistor R0, and a postamplifier 12 that has a positive input terminal to which the preamplifier positive output is input and a negative input terminal to which the preamplifier negative output is input, and obtains a postamplifier output vout. The postamplifier 12 is an input path to the positive input terminal. to The positive input resistor to be placed R4b And the negative input resistor where the input path to the negative input terminal is located. R4a And, post-amp output end The system includes a feedback resistor R5 positioned in the return path from the negative input terminal to the negative input terminal, and a resistor network connecting the positive input terminal to a reference power supply and ground, which supplies an offset voltage obtained by resistance division of the voltage of the reference power supply to the positive input terminal, and whose combined resistance value corresponds to the resistance value of the feedback resistor.

A magnetoresistive random access memory ("MRAM" for short) device includes at least one MRAM array. Each MRAM array includes a reference cell and a reference generator that generates a reference voltage between a first voltage and a second voltage, the first voltage being a function of a first current flowing through the first reference cell and the second voltage being a function of a second current flowing through the second reference cell, the first reference cell and the second reference cell are a pair of reference cells storing complementary values in a row of the MRAM array. Reference voltage can be automatically centered and track reading current changes of all PVT angles, and the reference voltage does not need to be adjusted. In some embodiments, the reference generator is used in cooperation with a current detection amplifier, and correct read data of all PVT angles can be reliably output.

Example implementations include a method, apparatus and integrated circuit (IC) for pre-charging a battery system. The IC may include an isolated gate driver configured to drive a switching device for selectively coupling a high voltage battery to a load capacitor. The IC may further include an integrated isolated current sense amplifier configured to sense current flowing through the switching device during a pre-charge operation. The IC may further include a programmable current limit circuit configured to regulate the pre-charge current to a predetermined value. The IC may further include a charge completion detection circuit configured to identify when the pre-charge operation is complete based on the sensed current or voltage across the load capacitor. The IC may further include a fault detection circuit configured to detect one or more fault conditions.

This application discloses a current-sensing amplifier circuit and calibration method, including: an input module, a reference voltage module, an amplifier, a feedback module, a first switch, and a second switch; the input module and the first switch are sequentially connected to the non-inverting input terminal of the amplifier; the input module and the second switch are sequentially connected to the inverting input terminal of the amplifier; the input module is used to switch between providing a non-zero detection voltage or a zero detection voltage to the amplifier; the inverting input terminal of the amplifier is also connected to the output terminal of the amplifier through the feedback module; the reference voltage module is connected in parallel with the first switch, and the reference voltage module is used to switch between directly outputting the reference voltage or outputting the reference voltage by voltage division; the feedback module is used to switch between providing unity gain or fixed gain to the amplifier. The embodiments of this application can accurately calibrate the detection voltage.

The utility model discloses a current test system capable of automatically adjusting a measuring range, comprising an ampere shift channel part, the ampere shift channel part comprises a switch MOSFET Q8, a sampling resistor R17, a resistor R18, a current detection amplifier U5, a push-pull comparator U6, a triode Q9, a diode D6, an anti-reverse diode D7, a triode Q10, a triode Q11, an electrolytic capacitor C2, a resistor R21, a resistor R22, a resistor R23, a resistor R24, a resistor R25 and a resistor R26; and the milliampere channel part comprises a switch MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) Q4, a sampling resistor R7, a resistor R8, a current detection amplifier U3, a push-pull comparator U4, a triode Q6, a diode D3, an anti-reverse diode D4, a diode D5 and a transistor Q5. According to the current test system capable of automatically switching the measuring range, a logic relation can be formed through current acquisition results of each gear of microampere, milliampere and ampere, and the current detection measuring range can be automatically switched according to the magnitude of an input current value.

The present invention addresses the problem of easily setting the input voltage of a preamplifier. The present invention includes a preamplifier (10) that obtains a preamplifier positive output (vc) and a preamplifier negative output (vb) corresponding to a difference between an upper-side voltage and a lower-side voltage of a current detection resistor (R0). The preamplifier (10) has a first operational amplifier (opa1), the upper voltage is input to the negative input end of the first operational amplifier, the lower voltage is input to the positive input end of the first operational amplifier, and the first operational amplifier (opa1) obtains a first operational amplifier positive output and a first operational amplifier negative output on the basis of the difference between the upper voltage and the lower voltage. The connection point of the negative input resistor of the first operational amplifier and the negative input end of the first operational amplifier is connected to a constant voltage source through a first input adjusting resistor, and the connection point of the positive input resistor of the first operational amplifier and the positive input end of the first operational amplifier is connected to the constant voltage source through a second input adjusting resistor.

The invention relates to the technical field of analog integrated circuits, in particular to a high-bandwidth isolation current detection amplifier circuit, a current detection method and a current detection chip. The current detection amplifier circuit comprises a high-voltage side circuit and a low-voltage side circuit which are electrically isolated; in the high-voltage side circuit and the low-voltage side circuit, a to-be-measured voltage is converted into a differential amplification voltage signal through a fully-differential differential amplifier; a feedback loop of a cross-isolation transmission path is formed by a first clamping amplifier, a first voltage-controlled oscillator, a second frequency voltage converter, a second voltage follower, a second voltage-controlled oscillator, a second clamping amplifier, a third frequency voltage converter and a first frequency voltage converter, so that a large bandwidth is provided; under the condition of process-voltage-temperature change, high current detection precision and accuracy are ensured, and influence caused by different processes, temperatures and the like of the high-voltage side circuit and the low-voltage side circuit is avoided.

A preamplifier obtains a preamplifier positive output and a preamplifier negative output; and a post-amplifier has a positive input end to which the preamplifier positive output is input and a negative input end to which the preamplifier negative output is input, and obtains a post-amplifier output. The post-amplifier includes: a positive side input resistor disposed in an input path to the positive input end; a negative side input resistor disposed in an input path to the negative input end; a feedback resistor disposed in a feedback path from a post-amplifier output end to the negative input end; and a resistor network in which an offset voltage obtained by performing resistance division to the voltage of the reference power supply is supplied to the positive input end, and a combined resistance value corresponds to the resistance value of the feedback resistor.

The present invention is to improve temperature dependence in a current sense amplifier. The current sense amplifier of the present invention measures a voltage drop in a drive transistor (LS) to measure a current flowing in the drive transistor (LS). The current sense amplifier includes a pre-amp to which a voltage across the drive transistor (LS) is inputted, to obtain a positive output and a negative output corresponding to a voltage difference of the inputted voltage across, and a switch (sw) connecting an input terminal of a common mode voltage (vcm) which is an operation reference of the pre-amp to the negative output. A change in the positive output caused by turning on / off the switch (sw) can be detected.

The present invention addresses the problem of easily setting an offset voltage of a post-amplifier. The present invention is provided with: a preamplifier (10) that obtains a preamplifier positive output (vc) and a preamplifier negative output (vb) corresponding to the difference between the upper voltage and the lower voltage of a current detection resistor (R0); and a post-amplifier (12) which has a positive input terminal to which the positive output of the pre-amplifier is input and a negative input terminal to which the negative output of the pre-amplifier is input, and which obtains a post-amplifier output (vout). A post-amplifier (12) includes: a positive-side input resistor (R4b) disposed on an input path leading to a positive input terminal; a negative-side input resistor (R4a) disposed on an input path leading to the negative input terminal; the feedback resistor (R5) is configured on a feedback path from the output end of the post amplifier to the negative input end; and a resistance network that connects the positive input terminal to the reference power supply and the ground, supplies an offset voltage to the positive input terminal, said offset voltage being obtained by dividing the voltage of the reference power supply by resistance, and has a combined resistance value corresponding to the resistance value of the feedback resistor.

A current detection amplifier that amplifies a detection signal of a current flowing to a current detection resistor and outputs the amplified detection signal to an AD converter, the current detection amplifier comprising: a first noise removal filter connected to one end of the current detection resistor and configured to have a first capacitance and a first resistor; and a first capacitance connection switch provided between the first capacitance of the first noise removal filter and the first sampling capacitance of the AD converter.

The present disclosure relates to aging compensation for a multi-resistor based current sense amplifier. A wireless power system includes a coil for receiving and transmitting wireless power, an integrated circuit, and one or more batteries. The integrated circuit includes a rectifier circuit, a current sense amplifier circuit, a calibration circuit, and a voltage regulator. The rectifier circuit receives an alternating current from the coil and generates a rectified voltage when the wireless power system is in a receive mode, and further transmits an alternating current to the coil when the wireless power system is in a transmit mode. The current sense amplifier circuit detects a current flowing between the rectifier and the voltage regulator. The calibration circuit generates a voltage used by firmware of the integrated circuit to calibrate an aging of resistors within the current sense amplifier circuit.

The invention provides a current monitoring circuit of a relay and a relay circuit structure. The current monitoring circuit comprises a K1 relay, a K2 relay, a K3 relay, a K4 relay, a sampling resistor, a load power supply, a current detection amplifier and an MCU. The common end of K1 is connected with the common end of K2, and the normally open end of K1 and the normally open end of K2 are connected in parallel and then are connected in series with the common end of K3 and the common end of K4 which are connected in parallel; a K1 relay coil, a K2 relay coil, a K3 relay coil and a K4 relay coil are respectively connected with a K1 common end, a K2 common end, a K3 common end and a K4 common end. The normally open end of the K3 and the normally open end of the K4 are connected with a sampling resistor, and the sampling resistor is connected with a load. The load power supply is connected with the load. The sampling resistor is connected with the current detection amplifier which is used for detecting the voltage difference between the two ends of the sampling resistor. The input end of the MCU is connected with the current detection amplifier; the MCU is used for determining the current value of the load loop according to the voltage difference.

A preamplifier obtains a preamplifier positive output and a preamplifier negative output corresponding to a difference between an upper voltage and a lower voltage of a current detection resistor. The preamplifier includes an operational amplifier, in which the upper voltage is input to an operational amplifier negative input end and the lower voltage is input to an operational amplifier positive input end, and which obtains an operational amplifier positive output and an operational amplifier negative output based on a difference between them. The connection point between an operational amplifier negative input resistor and the negative input end of the operational amplifier is connected to a constant voltage source via a first input adjustment resistor; and the connection point between an operational amplifier positive input resistor and the positive input end of the operational amplifier is connected to the constant voltage source via a second input adjustment resistor.

The invention relates to the technical field of circuits, in particular to a single-side current detection amplifier circuit, a chip and electronic equipment, and the single-side current detection amplifier circuit comprises an operational amplifier op, an enhanced PMOS (P-channel Metal Oxide Semiconductor) transistor MPF1, an enhanced PMOS transistor MPL1, an enhanced PMOS transistor MPF2, an enhanced PMOS transistor MPL2, a resistor Rla, a resistor R1b, a resistor Rda, a resistor Rdb, a resistor RS, a buffer BUF1 and a buffer BUF2. According to the single-side current detection amplifier circuit in the technical scheme provided by the embodiment of the invention, switching between a high-side circuit and a low-side circuit is not needed, and bidirectional current sampling can be realized through one circuit, so that the circuit scale is reduced, a large chip area does not need to be occupied when the circuit is integrated, and the cost is reduced. Therefore, the design and manufacturing cost is reduced.

The application discloses a high common-mode rejection ratio precision current detection amplifier, comprising: a high common-mode rejection ratio input stage circuit, which samples an input common-mode voltage signal through VCMCP1, outputs a boosted voltage to a first chopping switch and a PMOS input pair tube, and provides an input stage power potential; a transconductance amplification circuit, which adopts a chopping architecture, is connected with the high common-mode rejection ratio input stage circuit, and comprises a second chopping switch, a second amplifier, a third amplifier and a ripple suppression loop, is used for reducing a misadjustment voltage and an output ripple, and generates an output voltage VOUT; and a precision resistance trimming network, in which an input common-mode voltage signal is trimmed for resistance mismatch through a common-mode rejection ratio trimming circuit, and VCMCP2 provides a control voltage for trimming logic, so that a conduction resistance of a trimming switch is constant. The amplifier can effectively solve the problems of rail-to-rail input stage misadjustment voltage drift, resistance network mismatch and insufficient common-mode rejection ratio in the prior art.

The application belongs to the field of integrated circuits and analog electronic technology, and particularly relates to an adjustable gain isolated current detection amplifier, which comprises an input module, a programmable gain differential switched capacitor amplifier, an analog-to-digital converter (ADC), a capacitive isolation transmission module, a digital-to-analog converter (DAC) and a filtering and buffering module; the output end of the input module is connected with the input end of the programmable gain differential switched capacitor amplifier, the output end of the programmable gain differential switched capacitor amplifier is connected with the input end of the ADC, the output end of the ADC is connected with the input end of the capacitive isolation transmission module, the output end of the capacitive isolation transmission module is connected with the input end of the DAC, and the output end of the DAC is connected with the input end of the filtering and buffering module; the chopper modulation / demodulation circuit integrated in the switched capacitor amplifier of the application can suppress the input offset voltage and 1 / f noise of the switched capacitor amplifier, and ensure the basic precision of current detection.

The application discloses a signal combination circuit and a current induction amplification circuit. The signal combination circuit is used for generating a combined signal of a first signal and a second signal. The signal combination circuit comprises a first switch branch, a second switch branch, a third switch branch, a first energy storage branch, a second energy storage branch, a third energy storage branch, a first operational amplifier and a controller. The controller is used for controlling the first switch branch to be turned on, and controlling the second switch branch and the third switch branch to be turned off, so as to store the first signal on the first energy storage branch. The second switch branch is controlled to be turned on, and the first switch branch and the third switch branch are controlled to be turned off, so as to store the second signal on the second energy storage branch. The third switch branch is controlled to be turned on, and the first switch branch and the second switch branch are controlled to be turned off, so as to store the first signal and the second signal to the third energy storage branch, so as to generate the combined signal. In the above manner, the purpose of reducing transient peak can be achieved.

Easily set the input voltage of the preamplifier. [Solution] The preamplifier 10 includes a preamplifier positive output vc and a preamplifier negative output vb corresponding to the difference between the upper and lower voltages of a current sensing resistor R0. The preamplifier 10 has a first operational amplifier opa1 to which the upper voltage is input to the negative input terminal of the first operational amplifier and the lower voltage is input to the positive input terminal of the first operational amplifier, and which obtains a positive output and a negative output of the first operational amplifier based on the difference between these. The connection point between the negative input resistor of the first operational amplifier and the negative input terminal of the first operational amplifier is connected to a constant voltage source via a first input adjustment resistor, and the connection point between the positive input resistor of the first operational amplifier and the positive input terminal of the first operational amplifier is connected via a second input adjustment resistor. The aforementioned It is connected to a constant voltage source.

The application provides a current detection amplifier offset voltage test method, device and electronic equipment. The offset voltage of the input end of the to-be-tested current detection amplifier is adjusted, so that the output voltage can be within the range allowed by the to-be-tested current detection amplifier, and then the adjusted input end offset voltage is obtained. Finally, the offset voltage adjustment value and the offset voltage error are removed from the adjusted input end offset voltage, and the offset voltage test result is obtained. This method of adjusting the offset voltage of the input end of the to-be-tested current amplifier can make the output voltage within the output range allowed by the to-be-tested current detection amplifier, thereby avoiding the problem that the offset voltage is too small and cannot be tested.

The invention provides an alternating current on-off circuit based on MOS (Metal Oxide Semiconductor) tube control, which is characterized by comprising a zero-cross detection circuit, an MOS tube power switch circuit, a driving circuit and a bidirectional current detection and limit value overcurrent alarm circuit, the zero-cross detection circuit is provided with a voltage-regulator tube diode Z1 for stabilizing the voltage reduced by a divider resistor, and the MOS tube power switch circuit and the driving circuit are connected with the bidirectional current detection and limit value overcurrent alarm circuit; a Schottky diode D2 is adopted to clamp the negative phase voltage of the alternating current; the MOS tube power switch circuit and the driving circuit adopt a back-to-back MOS tube Q2 and a back-to-back MOS tube Q3, and a sampling resistor R4 is connected in series between the MOS tube Q2 and the MOS tube The bidirectional current detection and limit value overcurrent alarm circuit adopts two independent current detection amplifier chips, signal input ends of the two independent current detection amplifier chips are subjected to mutual reverse connection processing, and forward current and reverse current are subjected to differential detection respectively. According to the invention, the switch response speed is improved, and the electrical loss is greatly reduced; bidirectional current collection is realized under a single power supply system, and a hardware overcurrent alarm function is realized.