50 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 techniques and circuits, described herein, include solutions for error compensation in source measurement units (SMUs). An example SMU is capable of both sourcing current to a device under test (DUT) and measuring current through the DUT. An SMU may include a sensing resistor coupled in series with the DUT. A voltage across the sensing resistor may be measured by a current sensing amplifier in order to determine the output current through the DUT. In practice, the resistance of the sensing resistor may vary depending on manufacturing tolerances, etc. A gain of the current sensing amplifier may be calibrated in order to compensate for sensing resistor variance, which increases the accuracy with which current to the DUT can be sourced and measured.

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.

The invention relates to a capacitance feedback type current detection amplifier circuit, which comprises an operational amplifier, a feedback capacitor, a load capacitor, a reset switch, a first capacitor, a second capacitor, a first change-over switch and a second change-over switch, reference voltage is input to the in-phase input end of the operational amplifier, the output end of the operational amplifier is connected with the second end of the feedback capacitor and the first end of the load capacitor, the reset switch is connected with the feedback capacitor in parallel, the second end of the load capacitor is grounded, and the second end of the first capacitor is grounded. The second end of the second capacitor is selectively connected to the in-phase input end of the operational amplifier or the first change-over switch through the second change-over switch, and the first end of the first capacitor is selectively connected to the output end of the operational amplifier or the second change-over switch through the first change-over switch. According to the invention, the influence of noise random sampling values on the circuit can be suppressed.

[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.

The present application discloses a current sense amplifier and a current test device, applied to the field of current detection, comprising: a common mode voltage output circuit for outputting a common mode voltage; the negative feedback loop comprises a first operational amplifier and a differential-mode signal shifting circuit and is used for expanding the input common-mode voltage range and enabling the expanded input common-mode voltage range to be equivalent to a second operational amplifier; wherein the power supply end of the first operational amplifier is connected with the output end of the common-mode voltage output circuit, and the equivalent ground end of the first operational amplifier is connected with the equivalent ground potential smaller than the common-mode voltage. The common-mode voltage and the equivalent ground potential are connected to the power supply end of the first operational amplifier, so that the input common-mode voltage range of the current sensing amplifier is expanded, and the current sensing amplifier can normally work under the high-voltage condition.

The utility model provides a power adjusting device for realizing weak magnetic starting of a starting motor in a pulse width modulation mode, which belongs to the technical field of electronics and comprises a first high-side current detection amplifier, a second high-side current detection amplifier, an operational amplifier, a main switch circuit, a main control circuit and a feedback amplifier. The starting motor is provided with an armature loop and an excitation loop, the first sampling resistor is connected with the armature loop and the first high-side current detection amplifier, and the operational amplifier is connected with the first high-side current detection amplifier and the main control circuit; the second sampling resistor is connected with the excitation loop and the second high-side current detection amplifier, the feedback amplifier is connected with the second high-side current detection amplifier and the main control circuit, and the main control loop is connected with the main switch circuit; the main switch circuit is connected with the product power supply end and the second sampling resistor; the device is simple in process, convenient to operate, easy to adjust and high in practical value.

To enable a current-sense amplifier to be adapted to a wide range of DC voltages at input.SOLUTION: A current-sense amplifier 100 receives as input the upper-side voltage and the lower-side voltage of a current detection resistor 1, and obtains an output corresponding to the difference between the upper-side voltage and the lower-side voltage. A common voltage suppressor 12 includes: voltage dividing resistors R6a, R6b which are supplied with the upper-side voltage and the lower-side voltage at both ends and obtain a divided voltage; a first transistor M1 to one end of which the upper-side voltage is input, and the other end of which is connected to a prescribed power source; and a second transistor M2 to the one end of which the lower-side voltage is input, and the other end of which is connected to a prescribed power source. The control end of the first transistor M1 and the control end of the second transistor M2 are connected in common, and the divided voltage is input to a portion connected in common.SELECTED DRAWING: Figure 1

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.

The present invention provides a DC power management device based on autonomous lithium battery switching. The device has two power inputs, one of which is a switching power input directly used to power the DC power device; the other is a backup power input. When the switching power input is abnormal, a controller automatically switches to the backup power supply, and the backup power supply supplies power to the DC power device through a boost circuit. The device includes a power signal processing circuit, a charging management circuit, a boost circuit, a buck circuit, a comparator, a current sensing amplifier, a sampling resistor, an optocoupler, a transistor, a P-MOS transistor, and a controller. It can realize bidirectional uninterrupted power supply between the switching power supply and the backup power supply. The comparator monitors the status of the switching power supply. When it is abnormal, the power status IO outputs a high level. The transistor, optocoupler isolator, and P-MOS transistor are used to control the backup power supply through the boost circuit to achieve autonomous dual power switching.

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.

The utility model provides a current sampling range adjustable circuit and a battery management system.The current sampling range adjustable circuit comprises a current detection amplifier, a first resistor, a second resistor and a third resistor, the first resistor and the second resistor are connected with the forward input end and the reverse input end of the current detection amplifier respectively and are connected with a sampling resistor at the same time, and the third resistor is connected with the sampling resistor; the second end of the sampling resistor is grounded. And the third resistor is connected between the first end of the first resistor and the second end of the second resistor. The output end of the current detection amplifier is connected with the analog signal receiving end of the microcontroller. According to the circuit, the gain of the current detection amplifier is flexibly adjusted by adding the third resistor, so that the range of sampling current can be flexibly adjusted according to different input signals, the gain adjustment can be realized only through a simple resistance potential-divider network, the cost of the current sampling range adjustable circuit is effectively reduced, and the application range of the current sampling range adjustable circuit is expanded. Therefore, the flexibility and practicability of the current sampling range adjustable circuit are improved.

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.

Current detection circuit, circuit device, and solenoid control device. The current detection circuit includes an operational amplifier, a current sense amplifier including a first resistor and a second resistor, and a level shifter. The first resistor is provided between one end of a shunt resistor and a first input node of the operational amplifier. The second resistor is provided between the other end of the shunt resistor and a second input node of the operational amplifier. The level shifter controls the current supplied to the first and second input nodes in accordance with the voltage of the one end of the shunt resistor, thereby controlling the voltages of the first and second input nodes.

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.