CN109444513A - A kind of bimag Low Drift Temperature Hall current sensor - Google Patents
A kind of bimag Low Drift Temperature Hall current sensor Download PDFInfo
- Publication number
- CN109444513A CN109444513A CN201811481718.1A CN201811481718A CN109444513A CN 109444513 A CN109444513 A CN 109444513A CN 201811481718 A CN201811481718 A CN 201811481718A CN 109444513 A CN109444513 A CN 109444513A
- Authority
- CN
- China
- Prior art keywords
- resistance
- bimag
- hall
- current sensor
- low drift
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000005291 magnetic effect Effects 0.000 claims abstract description 47
- 238000007142 ring opening reaction Methods 0.000 claims abstract description 4
- 230000006698 induction Effects 0.000 claims description 10
- 239000003990 capacitor Substances 0.000 claims description 9
- 239000004020 conductor Substances 0.000 claims description 2
- 230000035945 sensitivity Effects 0.000 abstract description 4
- 239000011162 core material Substances 0.000 description 15
- 230000005611 electricity Effects 0.000 description 6
- 238000013461 design Methods 0.000 description 5
- 239000000696 magnetic material Substances 0.000 description 5
- 238000005259 measurement Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000035699 permeability Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measuring Magnetic Variables (AREA)
- Hall/Mr Elements (AREA)
Abstract
A kind of bimag Low Drift Temperature Hall current sensor, the magnetic core that two geometric dimensions are the same, the opening different magnet ring of air gap thickness is as sensor, two completely the same Hall chips of characteristic are respectively put at two magnet ring opening air gaps, two Hall chip outputs are respectively connected to the positive and negative input terminal of Low Drift Temperature difference amplifier, constitute bimag Low Drift Temperature Hall current sensor.Two Hall chip output voltages are subtracted each other using subtracter, the two difference in voltage is obtained, and amplified to this voltage difference with amplifier, obtains the voltage output proportional with electric current to be measured.A kind of bimag Low Drift Temperature Hall current sensor of the present invention can be obviously improved open loop Hall current sensor temperature drift in the case where not needing temperature-compensation circuit, improve sensitivity and precision.
Description
Technical field
The present invention relates to a kind of Hall current sensor, specifically a kind of bimag Low Drift Temperature Hall current sensor.
Background technique
Open loop Hall current sensor is because its structure is simple, low cost, low-power consumption, good accuracy, test cross direct current, does not need
The features such as being in contact with primary circuit, being able to achieve the on-line monitoring of mA~kA range is widely used in technical grade Super-Current Measurement
(200A or more).
The performance of open loop Hall current sensor depends on hall device and provides the magnet ring of poly- magnetic effect, and hall device is made
For a kind of semiconductor devices, zero point and sensitivity can generate drift with the variation of temperature, in addition to this, since magnet ring is
Soft magnetic materials, magnetic magnetic conductivity can also be greatly lowered with the rising of temperature, above-mentioned so as to cause the reduction of poly- magnetic effect
Two reasons affect the temperature stability and current measurement precision of open loop Hall current sensor.Existing part high-precision hall
Device inside has been integrated with temperature-compensation circuit, can satisfy technical grade temperature requirement, such as DS-CC6501, works normally
Temperature is -40 DEG C~120 DEG C, will not be had an impact to current measurement after being used for Hall current sensor design, therefore,
The temperature drift of open loop Hall current sensor is mainly generated by magnet ring.Existing solution mainly has two major classes: one kind is logical
Excess temperature compensates to eliminate temperature drift problem；Another kind of is to constitute closed-loop Hall current sensor by increasing a feedback coil.
Compensation schemes are broadly divided into two kinds, one is hardware compensating method, need to be known in advance core material, hall device and temperature
The relationship of three, but the relationship between three is complicated, simply linearly or nonlinearly circuit is difficult to realize in gamut scope
Temperature compensation needs, furthermore compensation circuit hardware configuration is complicated, increases sensor cost.Another kind is software compensation, still
It needs to complete by processor, additional increases system complexity.Closed-loop Hall current sensor is because of its closed loop configuration
For open loop Hall current sensor, there is some superiority in precision, temperature drift, but when measuring 200A or more high current
It waits, closed-loop Hall current sensor is limited by volume, process complexity, cost, power consumption of current sensor etc., is unfavorable for industry
The on-line monitoring of grade high current.
Summary of the invention
In order to reduce the temperature drift of open loop Hall current sensor, overcome the deficiencies in the prior art, the present invention provides a kind of double
Magnetic core Low Drift Temperature Hall current sensor can be obviously improved open loop Hall electricity in the case where not needing temperature-compensation circuit
Flow sensor temperature drift improves sensitivity and precision.
The technical scheme adopted by the invention is as follows:
A kind of bimag Low Drift Temperature Hall current sensor, two geometric dimensions are the same, opening air gap thickness is different
Magnetic core of the magnet ring as sensor, two completely the same Hall chips of characteristic are respectively put at two magnet ring opening air gaps, and two
A Hall chip output is respectively connected to the positive and negative input terminal of Low Drift Temperature difference amplifier, constitutes bimag Low Drift Temperature Hall current
Sensor.
Two Hall chip output voltages are subtracted each other using subtracter, obtain the two difference in voltage, and with amplifier to this
Voltage difference amplifies, and obtains the voltage output proportional with electric current to be measured.
Hall current sensor principle of the present invention is shown in Fig. 1, as tested electric current IPWhen by sensor magnetic core, conducting wire week
The magnetic field of generation is enclosed by magnetic core C1With the magnet accumulating cap of C2, make respectively to generate a magnetic field H above Hall chip DS-CC6501, this
In because magnetic core width of air gap it is different, the corresponding magnetic induction density B of two Hall chips is different, thus two suddenly
Your chip output voltage is different, after a subtracter, output voltage UoThe voltage difference generated for two Hall chips exists
By the voltage after in-phase proportion amplifier.
The bimag Hall current sensor is realized especially by three parts, is respectively to be used to provide two Halls
The bimag magnetic circuit of difference magnetic induction intensity needed for device, the subtracter electricity for subtracting each other two hall devices generation voltages
Road, the in-phase proportion amplifying circuit for reaching told sensor target gain.
The bimag magnetic circuit for difference magnetic induction intensity needed for providing two hall devices is specifically identical by two
Magnet ring opens the bimag that different air gap is constituted.
For an electrified wire, length long enough is I by electric currentP, the magnetic strength of generation at distance center r
Answer intensity B that can be indicated with following formula:
Magnetic induction density B when electrified wire passes through annulus, in magnet ringcoreIt can be indicated with following formula:
μ in formula0For vacuum relative permeability, value 1；μrFor magnet ring relative permeability；D is annulus outer diameter；D is circle
Ring internal diameter.
After magnetic core opening, due to air gap lairMuch smaller than magnet ring size, it is believed that the magnetic field of opening is continuous and uniform
, according to Ampere ring road rule, can obtain:
When temperature is raised, soft magnetic materials μrDecline, so as to cause BairDecline, this is Hall current sensor magnetic circuit part
The main reason for generation temperature drift divided.
Because selected magnetic core is soft magnetic materials, magnetic conductivity is high,So gas
Magnetic induction density B at gapairSimplify are as follows:
Magnetic induction intensity is size linear change with air gap at magnetic core air gap as can be seen from the above equation, further,
Due to C1And C2Opening size is different, causes the magnetic induction intensity at air gap different, if magnetic core C1Magnetic induction intensity at air gap
For Bair1, C2Magnetic induction intensity at air gap is Bair2, so:
Two identical hall devices are respectively as follows: in the voltage for appealing the generation of two air gaps
Wherein U1 is hall device in magnetic core C1The voltage generated at air gap, U2 are hall device in magnetic core C2It is produced at air gap
Raw voltage.
Further, the subtraction circuit for subtracting each other two hall devices generation voltages is by operational amplifier
OP07, resistance R1, resistance R2, resistance R3 and resistance R4 are constituted.The one end resistance R1 connects Hall chip H1, the resistance R1 other end point
It Lian Jie not the one end resistance R3, the first operational amplifier non-inverting input terminal；The one end resistance R2 connects Hall chip H2, and resistance R2 is another
End is separately connected the one end resistance R4, the first operational amplifier inverting input terminal；The resistance R3 other end connects the end GND, and resistance R4 is another
One end connects the first operational amplifier output terminal.
The voltage that two hall devices generate is subtracted each other, it is hereby achieved that:
Wherein U3 is the voltage difference that two hall devices generate.
Further, for reaching the in-phase proportion amplifying circuit of told sensor target gain by operational amplifier
OP07, resistance R5, resistance R6, resistance R7, capacitor C1 are constituted.The one end resistance R5 connects the end GND, resistance R5 other end connection second
Operational amplifier non-inverting input terminal；The one end resistance R6 connects the first operational amplifier output terminal, and the resistance R6 other end is separately connected
The one end resistance R7, the one end capacitor C1, second operational amplifier inverting input terminal；The resistance R7 other end, the connection of the capacitor C1 other end
Second operational amplifier OP07 output end.
It realizes that target gain needs to adjust the size of resistance R6 and resistance R7, is embodied as:
A kind of bimag Low Drift Temperature Hall current sensor of the present invention, has the beneficial effect that:
1: K as can be seen from the above equationHI is definite value, and the output voltage of the bimag Hall current sensor is with outer magnetic
Field namely tested electric current IPLinear change.Sensitivity can be by selecting highly sensitive Hall chip and its corresponding signal to handle electricity
It improves on road.By formula it is found that when temperature is raised, Bair2And Bair1Reduce simultaneously, but Bair2-Bair1It is basically unchanged, so this biography
Sensor can reduce temperature drift compared to existing open loop Hall current sensor.
2: compared with prior art, in the case where not needing to introduce temperature-compensation circuit, can reduce Hall current biography
Temperature drift on sensor magnetic circuit improves measurement accuracy and Hall electricity of the Hall current sensor in large temperature range
The temperature stability of flow sensor.
3: not needing to eliminate temperature drift by temperature-compensating, reduce open loop Hall electricity using bimag subtraction circuit
The temperature drift of flow sensor meets the open loop Hall current sensor performance requirement for being applied to technical grade Super-Current Measurement.It should
For scheme is compared with temperature-compensation circuit: structure is simple, versatile and can be substantially reduced open loop Hall current sensor temperature
Drift.
Detailed description of the invention
Present invention will be further explained below with reference to the attached drawings and examples.
Fig. 1 is the principle of the present invention figure.
Fig. 2 is hall device circuit diagram.
Fig. 3 is subtraction circuit figure.
Fig. 4 is gain enlarged diagram.
Fig. 5 is hardware circuit diagram of the invention.
Specific embodiment
A kind of bimag Low Drift Temperature Hall current sensor, two geometric dimensions are the same, opening air gap thickness is different
Magnetic core of the magnet ring as sensor, two completely the same Hall chips of characteristic are respectively put at two magnet ring opening air gaps, and two
A Hall chip output is respectively connected to the positive and negative input terminal of Low Drift Temperature difference amplifier, constitutes bimag Low Drift Temperature Hall current
Sensor.
Two Hall chip output voltages are subtracted each other using subtracter, obtain the two difference in voltage, and with amplifier to this
Voltage difference amplifies, and obtains the voltage output proportional with electric current to be measured.
A kind of bimag Low Drift Temperature Hall current sensor is invented, two part magnetic circuit parts and circuit part are divided into.
(1), the design of magnetic circuit part:
(1), magnet ring structure form: the shape of magnet ring has rectangular, round two kinds of structures, and square structure is used for the side of high current
Type busbar or bus, circular configuration are used for general round conductor.So opening number is one, and inner circle is straight using circular configuration
Diameter 16mm, outside diameter 28mm.
(2), opening size designs: according toIt is found that the size of opening directly determines the magnetic strength at magnet ring
Answer intensity size.Consider that opening size is small, then magnetic field continuity, uniformity are good from the continuity and uniformity in magnetic field.But it is too small
Opening size, and easily magnet ring is caused to be saturated, output is caused to be distorted.So magnet ring C of the present invention1Take 2cm, C2Take 1.5cm.
(3), magnet ring material selects: the selection for designing double soft magnetic materials mainly considers at 3 points: high magnetic permeability, quickly to gather
Magnetic；Low-coercivity, magnetic hystersis loss are lower；Low-temperature coefficient reduces Sensor temperature drift.The present invention is perm conjunction using soft magnetic materials
Gold, the material have high magnetic permeability, low-coercivity feature.
(2), the design of circuit part:
(1), as shown in Fig. 2, selected chip is two identical hall device CC6501, as tested electric current IPBy when,
The voltage U1 and U2 generated under same core different air gap:
The effect of capacitor is to be shorted high-frequency interferencing signal into ground, reduces sensor noise.
(2), according to design scheme, operational amplifier needs the accurate operational amplifier of track to track double operational Low Drift Temperature, this
Invention uses operational amplifier for OP07.
(3), U1 and U2 is obtained after the subtracter being made of operational amplifier OP07, resistance R1, resistance R2, resistance R3
Voltage be U3, U3=U1-U2=KHI(Bair2-Bair1).It is illustrated in figure 3 subtracter physical circuit figure.
(4), to obtain target gain, U3It also needs by ratio enlargement, as shown in figure 4, resistance R5, resistance R6, electricity
It hinders R7 and capacitor C1 and constitutes scaling circuit of the present invention, after ratio enlargement
Sensor can be changed in the size for adjusting resistance R6 and resistance R7
Target gain.Capacitor C1Effect is reduction operational amplifier self-noise.
(5)、U4For inventive sensor final output voltage.Entire hardware circuit diagram is as shown in Figure 5.
Claims (6)
1. a kind of bimag Low Drift Temperature Hall current sensor, it is characterised in that: two geometric dimensions are the same, be open air gap thickness
Magnetic core of the different magnet ring as sensor, two completely the same Hall chips of characteristic are respectively put into two magnet ring opening gas
At gap, two Hall chip outputs are respectively connected to the positive and negative input terminal of Low Drift Temperature difference amplifier, constitute bimag Low Drift Temperature suddenly
That current sensor.
2. a kind of bimag Low Drift Temperature Hall current sensor according to claim 1, it is characterised in that: utilize subtracter will
Two Hall chip output voltages subtract each other, and both obtain difference in voltage, and amplified to this voltage difference with amplifier, obtain with
The proportional voltage output of electric current to be measured.
3. a kind of bimag Low Drift Temperature Hall current sensor according to claim 1, characterized by comprising:
For difference magnetic induction intensity needed for two hall devices are provided bimag magnetic circuit,
For by two hall devices generate subtraction circuit that voltages subtract each other,
For reaching the in-phase proportion amplifying circuit of sensor target gain.
4. a kind of bimag Low Drift Temperature Hall current sensor according to claim 3, characterized by comprising:
The bimag magnetic circuit includes that two identical magnet rings open the bimag that different air gap is constituted,
A kind of bimag Low Drift Temperature Hall current sensor according to claim 3, it is characterised in that:
The subtraction circuit includes the first operational amplifier, resistance R1, resistance R2, resistance R3, resistance R4；
The one end resistance R1 connects Hall chip H1, and it is same that the resistance R1 other end is separately connected the one end resistance R3, the first operational amplifier
Phase input terminal；The one end resistance R2 connects Hall chip H2, and the resistance R2 other end is separately connected the one end resistance R4, the first operation amplifier
Device inverting input terminal；The resistance R3 other end connects the end GND, and the resistance R4 other end connects the first operational amplifier output terminal.
5. a kind of bimag Low Drift Temperature Hall current sensor according to claim 4, it is characterised in that:
The in-phase proportion amplifying circuit includes second operational amplifier, resistance R5, resistance R6, resistance R7, capacitor C1；
The one end resistance R5 connects the end GND, and the resistance R5 other end connects second operational amplifier non-inverting input terminal；The one end resistance R6 connects
The first operational amplifier output terminal is connect, the resistance R6 other end is separately connected the one end resistance R7, the one end capacitor C1, the second operation amplifier
Device inverting input terminal；The resistance R7 other end, the capacitor C1 other end connect second operational amplifier OP07 output end.
6. a kind of bimag Low Drift Temperature Hall current sensor according to claim 1, it is characterised in that:
Magnet ring structure form: the shape of magnet ring is rectangular or round, square busbar or mother of the square structure for high current
Line, circular configuration are used for general round conductor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811481718.1A CN109444513A (en) | 2018-12-05 | 2018-12-05 | A kind of bimag Low Drift Temperature Hall current sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811481718.1A CN109444513A (en) | 2018-12-05 | 2018-12-05 | A kind of bimag Low Drift Temperature Hall current sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109444513A true CN109444513A (en) | 2019-03-08 |
Family
ID=65557130
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811481718.1A Pending CN109444513A (en) | 2018-12-05 | 2018-12-05 | A kind of bimag Low Drift Temperature Hall current sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109444513A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109921274A (en) * | 2019-04-17 | 2019-06-21 | 大族激光科技产业集团股份有限公司 | The protection circuit of laser light path and guard method |
| CN110146737A (en) * | 2019-05-28 | 2019-08-20 | 杭州电子科技大学 | A kind of wide range current sensor based on shunt magnetic structure |
| CN111157776A (en) * | 2020-01-14 | 2020-05-15 | 清华大学 | Double-magnetic-core sensor for insulation leakage current of power equipment |
| CN111157777A (en) * | 2020-01-14 | 2020-05-15 | 清华大学 | Design method of double-magnetic-core differential leakage current measurement sensor |
| CN112255583A (en) * | 2020-10-29 | 2021-01-22 | 杭州电力设备制造有限公司 | Error compensation method for direct current transformer |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2689240Y (en) * | 2004-04-28 | 2005-03-30 | 华中科技大学 | Double detecting current sensors |
| CN201522523U (en) * | 2008-12-24 | 2010-07-07 | 北京华电云通电力技术有限公司 | Zero-temperature-drift current sensor |
| CN103364612A (en) * | 2013-07-05 | 2013-10-23 | 华中科技大学 | Dual-Hall element current sensor |
| CN205080181U (en) * | 2015-11-06 | 2016-03-09 | 南京中旭电子科技有限公司 | High temperature resistant hall current sensor |
| CN106645863A (en) * | 2015-10-30 | 2017-05-10 | 北京柏艾斯科技有限公司 | Voltage sensor based on dual fluxgates |
| CN207662953U (en) * | 2017-11-13 | 2018-07-27 | 北京柏艾斯科技有限公司 | A kind of high precision closed loop Hall current sensor |
| CN209432889U (en) * | 2018-12-05 | 2019-09-24 | 三峡大学 | A kind of bimag Low Drift Temperature Hall current sensor |
-
2018
- 2018-12-05 CN CN201811481718.1A patent/CN109444513A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2689240Y (en) * | 2004-04-28 | 2005-03-30 | 华中科技大学 | Double detecting current sensors |
| CN201522523U (en) * | 2008-12-24 | 2010-07-07 | 北京华电云通电力技术有限公司 | Zero-temperature-drift current sensor |
| CN103364612A (en) * | 2013-07-05 | 2013-10-23 | 华中科技大学 | Dual-Hall element current sensor |
| CN106645863A (en) * | 2015-10-30 | 2017-05-10 | 北京柏艾斯科技有限公司 | Voltage sensor based on dual fluxgates |
| CN205080181U (en) * | 2015-11-06 | 2016-03-09 | 南京中旭电子科技有限公司 | High temperature resistant hall current sensor |
| CN207662953U (en) * | 2017-11-13 | 2018-07-27 | 北京柏艾斯科技有限公司 | A kind of high precision closed loop Hall current sensor |
| CN209432889U (en) * | 2018-12-05 | 2019-09-24 | 三峡大学 | A kind of bimag Low Drift Temperature Hall current sensor |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109921274A (en) * | 2019-04-17 | 2019-06-21 | 大族激光科技产业集团股份有限公司 | The protection circuit of laser light path and guard method |
| CN110146737A (en) * | 2019-05-28 | 2019-08-20 | 杭州电子科技大学 | A kind of wide range current sensor based on shunt magnetic structure |
| CN111157776A (en) * | 2020-01-14 | 2020-05-15 | 清华大学 | Double-magnetic-core sensor for insulation leakage current of power equipment |
| CN111157777A (en) * | 2020-01-14 | 2020-05-15 | 清华大学 | Design method of double-magnetic-core differential leakage current measurement sensor |
| CN112255583A (en) * | 2020-10-29 | 2021-01-22 | 杭州电力设备制造有限公司 | Error compensation method for direct current transformer |
| CN112255583B (en) * | 2020-10-29 | 2023-04-14 | 杭州电力设备制造有限公司 | Error compensation method for direct current transformer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN209432889U (en) | A kind of bimag Low Drift Temperature Hall current sensor | |
| CN109444513A (en) | A kind of bimag Low Drift Temperature Hall current sensor | |
| CN103560760B (en) | Amplifying circuit and measuring device | |
| US10101413B2 (en) | Magnetic field detection device | |
| CN100501415C (en) | Highly anti-interference alternating-current/magnetic field sensor | |
| US10955497B2 (en) | Phase compensation circuit, magnetic induction imaging device and phase compensation method | |
| CN103308075B (en) | Current output-type linear hall-effect sensor | |
| CN103616550A (en) | Giant magnetoresistance current sensor | |
| CN103575960A (en) | Giant magnetoresistance effect current sensor | |
| CN104729396A (en) | High-temperature eddy-current displacement sensor temperature compensation method based on temperature online measurement and sensing device | |
| CN114264861B (en) | Current sensor | |
| CN111150114A (en) | Temperature measurement circuit, electronic smoking set and temperature measurement method | |
| CN113917215B (en) | Current sensor | |
| CN113411074B (en) | Hall sensor switch and electronic equipment | |
| CN110095643A (en) | A kind of four air gap open loop Hall current sensor of single magnetic core | |
| CN105988034A (en) | Current detection device | |
| CN110095644A (en) | A kind of novel high-precision open loop Hall current sensor | |
| CN201926944U (en) | Microampere precise constant flow source circuit | |
| CN203630195U (en) | Giant magnetoresistance current sensor | |
| CN105842511A (en) | Dual-coil anti-magnetic-type current transformer | |
| WO2018230262A1 (en) | Ultra high-sensitivity micro magnetic sensor | |
| CN109358221A (en) | A kind of low magnetic hysteresis current sensor | |
| CN105807117B (en) | Current sensing circuit for current measuring probe and current measuring probe thereof | |
| CN116699223A (en) | Current detection system and method based on TMR sensor | |
| US20130043892A1 (en) | Resistance measurement circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |