ClassID:

172008

G01R33/04 - CPC Classification

Classification description:

Arrangements or instruments for measuring magnetic variables; Measuring direction or magnitude of magnetic fields or magnetic flux using the flux-gate principle

Sub-classes:
Recent Application in this class:
#1
20260009869
2026-01-08

METHOD FOR ESTIMATING NOISE OF SOFT MAGNETIC CORE

#2
20250261890
2025-08-21

Systems and Methods for Biomagnetic Field Imaging

#3
20250180619
2025-06-05

DETECTION METHOD, SYSTEM, AND STORAGE MEDIUM FOR FLUXGATE SENSOR NOISE

#4
20250155527
2025-05-15

EXCITATION CIRCUIT, CURRENT SENSOR, AND MEASURING DEVICE

#5
20250020740
2025-01-16

LAYOUTS FOR INTERLEVEL CRACK PREVENTION IN FLUXGATE TECHNOLOGY MANUFACTURING

#6
20250014806
2025-01-09

COMMON MODE FILTERING DEVICE AND CHARGING SYSTEM FOR ELECTRIC OR HYBRID VEHICLES

#7
20250000416
2025-01-02

Signal Processing Methods and Systems for Biomagnetic Field Imaging

#8
20240426948
2024-12-26

RING CORE CURRENT TRANSDUCER FOR FLUX DETECTION

#9
20240426942
2024-12-26

ELECTRIC CIRCUITRY FOR FAULT CURRENT DETECTION IN AN ELECTRIC VEHICLE CHARGING STATION

#10
20240329163
2024-10-03

MONITORING UNIT COMPRISING AN INTEGRATED MAGNETIC FIELD SENSOR

#11
20240306969
2024-09-19

Systems and methods for biomagnetic field imaging

#12
20240306927
2024-09-19

Signal processing methods and systems for biomagnetic field imaging

#13
20240302457
2024-09-12

MAGNETIC FIELD DETECTION SENSING DEVICE AND FLUXGATE CHIP PACKAGING STRUCTURE THEREOF

#14
20240297317
2024-09-05

METHOD AND APPARATUS OF DETECTING PROTON EXCHANGE MEMBRANE FUEL CELL OPERATING STATE

#15
20240230513
2024-07-11

CORROSION ANALYSIS USING MAGNETIC FLUX LEAKAGE MEASUREMENTS

#16
20240133796
2024-04-25

Corrosion analysis using magnetic flux leakage measurements

#17
20240111001
2024-04-04

FLUXGATE MAGNETIC SENSOR

#18
20240061024
2024-02-22

Single winding core-insensitive fluxgate current sensor

#19
20240012072
2024-01-11

MAGNETIC DETECTION APPARATUS AND CURRENT DETECTION APPARATUS

#20
20230408559
2023-12-21

FLUXGATE CURRENT SENSOR AND CURRENT MEASUREMENT METHOD

#21
20230400534
2023-12-14

SENSOR USING A FIELD GRADIENT IN A GIVEN VOLUME

#22
20230328942
2023-10-12

Alloy of extremely low magnetic noise

#23
20230213598
2023-07-06

Manufacturing method for fluxgate chip

#24
20230084963
2023-03-16

Device, system and method for detecting leakage current for traction power system

#25
20230055691
2023-02-23

Current sensor

#26
20230026610
2023-01-26

Nanowire characterization and identification

#27
20220357366
2022-11-10

Fluxgate current transducer

#28
20220342009
2022-10-27

Method and device for eliminating offset of fluxgate magnetometer

#29
20220342008
2022-10-27

Sensor systems, method for determining a position of a magnet system, an operating unit, and a computer program

#30
20220260614
2022-08-18

CURRENT DETECTOR

#31
20220260613
2022-08-18

Method of reducing noise in a fluxgate current transducer

#32
20220196872
2022-06-23

System and method for a security post

#33
20220196871
2022-06-23

System and method for detecting objects

#34
20220146601
2022-05-12

Millimeter wave magnetic sensor

#35
20210373091
2021-12-02

Sensor package

#36
20210356534
2021-11-18

Current sensor with magnetic field circulation

#37
20210341552
2021-11-04

Magnetic freepoint indicator tool

#38
20210341551
2021-11-04

Magnetic freepoint indicator tool

#39
20210319693
2021-10-14

System and method for parking detection and identification of moveable apparatus

#40
20210255222
2021-08-19

Current sensor with flux gate

#41
20210239773
2021-08-05

Sensor, method and system for detecting one or more properties of a magnetic field

#42
20210233903
2021-07-29

Integrated fluxgate device

#43
20210231894
2021-07-29

Non-metallic layer stranded optical cable with reversal point capable of being positioned and method for detecting the reversal point

#44
20200379017
2020-12-03

Toroidal fluxgate current transducer

#45
20200319269
2020-10-08

Magnetic sensor, sensor module, and diagnostic device

#46
20200264245
2020-08-20

Battery management unit with a PCB integrated fluxgate current sensor

#47
20200249285
2020-08-06

Near magnetic field variation detection system and detection method thereof

#48
20200191546
2020-06-18

Magnetic position determination systems and methods

#49
20200116802
2020-04-16

Triaxial magnetism detecting apparatus and satellite

#50
20200064415
2020-02-27

Compass including magnetic field sensor

#51
20200011900
2020-01-09

Neel effect® isolated DC/AC current sensor incorporated in a PCB

#52
20200003848
2020-01-02

Integrated fluxgate magnetic gradient sensor

#53
20190331742
2019-10-31

Layouts for interlevel crack prevention in fluxgate technology manufacturing

#54
20190324097
2019-10-24

Highly sensitive, low power fluxgate magnetic sensor integrated onto semiconductor process technologies

#55
20190317135
2019-10-17

Current sensor with fluxgate

#56
20190256905
2019-08-22

Magnetic flux density based DNA sequencing

#57
20190219541
2019-07-18

Planar array pipeline inspection tool

#58
20190211458
2019-07-11

PROCESS FOR NiFe FLUXGATE DEVICE

#59
20190204394
2019-07-04

Pendulum system

#60
20190170693
2019-06-06

Apparatus and method for the non-destructive determination of the content of the magnetizable and/or non-magnetizable portion of a sample

#61
20190167136
2019-06-06

Biomagnetism measuring device

#62
20190154733
2019-05-23

CURRENT DETECTION DEVICE HAVING MULTI-LAYERED PCB CORE STRUCTURE

#63
20190113544
2019-04-18

MAGNETIC SENSOR AND CURRENT SENSOR INCLUDING THE SAME

#64
20190107564
2019-04-11

Current sensor

#65
20190102585
2019-04-04

Nanowire characterization and identification

#66
20190101601
2019-04-04

REDUCTION OF MAGNETIC SENSOR COMPONENT VARIATION DUE TO MAGNETIC MATERIALS THROUGH THE APPLICATION OF MAGNETIC FIELD

#67
20180373020
2018-12-27

Cascaded electrical device bus structure systems and methods

#68
20180333070
2018-11-22

Apparatuses for Detecting and/or Destroying Abnormal Tissue, Such as Cancer Tissue, and Related Methods

#69
20180284310
2018-10-04

Minute magnetic body detecting sensor and foreign substance detecting device

#70
20180259561
2018-09-13

WEARABLE CURRENT SENSOR

#71
20180213313
2018-07-26

Magnetic pivot sensor for headset microphone

#72
20180209266
2018-07-26

Measuring instruments, systems and magnetic gradiometers

#73
20180196087
2018-07-12

Device for measuring a magnetic field

#74
20180195895
2018-07-12

Magnetic field based micro-vibration measurement device and measuring method thereof

#75
20180180658
2018-06-28

Monitoring of power cables with distributed fibre optic sensing

#76
20180149678
2018-05-31

Apparatus for measuring an electric current through a bus bar

#77
20180106874
2018-04-19

Inductance element for magnetic sensor and current sensor including the same

#78
20180096784
2018-04-05

Fluxgate device with low fluxgate noise

#79
20180087161
2018-03-29

Process for NiFe fluxgate device

#80
20180080961
2018-03-22

Isolated DC current and voltage sensor with low crosstalk

#81
20170346000
2017-11-30

Magnetic core

#82
20170343622
2017-11-30

Highly sensitive, low power fluxgate magnetic sensor integrated onto semiconductor process technologies

#83
20170342478
2017-11-30

Magnetic flux density based DNA sequencing

#84
20170341934
2017-11-30

Selective patterning of titanium encapsulation layers

#85
20170336274
2017-11-23

Systems and methods for determining mechanical stress of machinery

#86
20170330666
2017-11-16

Solenoid Actuator

#87
20170328961
2017-11-16

Dual-axis fluxgate device

#88
20170322052
2017-11-09

Magnetoresistive wheatstone measuring bridge and angle sensor having at least two such measuring bridges

#89
20170316875
2017-11-02

Fluxgate device with low fluxgate noise

#90
20170299666
2017-10-19

Rapid Magnetic Hotspot Detector

#91
20170299665
2017-10-19

Linear positioning system utilizing helically polarized magnet

#92
20170299396
2017-10-19

APPARATUS, SYSTEM, AND METHOD FOR REFINING GEOGRAPHICAL LOCATION BASED ON DYNAMIC CHARACTERISTICS OF HELMET

#93
20170267521
2017-09-21

Selective patterning of an integrated fluxgate device

#94
20170261564
2017-09-14

Reduction of magnetic sensor component variation due to magnetic materials through the application of magnetic field

#95
20170250641
2017-08-31

Flux estimation for fault tolerant control of PMSM machines for EPS

#96
20170234942
2017-08-17

LAYOUTS FOR INTERLEVEL CRACK PREVENTION IN FLUXGATE TECHNOLOGY MANUFACTURING

#97
20170229639
2017-08-10

Integrated fluxgate device with three-dimensional sensing

#98
20170219632
2017-08-03

Current transducer with fluxgate detector

#99
20170213956
2017-07-27

Integrated fluxgate device

#100
20170201283
2017-07-13

Antenna adapter

#101
20170188881
2017-07-06

Transducer with magnetic nanowire array

#102
20170175259
2017-06-22

Magnetic field annealing for integrated fluxgate sensors

#103
20170153299
2017-06-01

Integrated dual axis fluxgate sensor using double deposition of magnetic material

#104
20170125151
2017-05-04

Magnetic sensor and current sensor including the same

#105
20170089986
2017-03-30

Measuring arrangement for detecting a magnetic unidirectional flux in the core of a transformer

#106
20170082692
2017-03-23

Method and system for detecting rotor fault using triaxial magnetic field sensor

#107
20170067964
2017-03-09

Method for measuring the ageing of permanent magnets of a synchronous machine fitted with an angular position sensor

#108
20160363636
2016-12-15

Sensor apparatus, production method for a sensor apparatus having at least one magnetic core and method for determining a field strength of a magnetic field in at least one spatial direction

#109
20160349334
2016-12-01

Integrated fluxgate magnetic gradient sensor

#110
20160339948
2016-11-24

Sensor device and electric power steering apparatus using same

#111
20160334473
2016-11-17

Fluxgate magnetic field detection method and circuit

#112
20160306012
2016-10-20

System for condition monitoring of electric machine, mobile phone and method thereof

#113
20160291096
2016-10-06

Magnetic sensor device and manufacturing method for a magnetic sensor device

#114
20160274197
2016-09-22

Integrated dual axis fluxgate sensor using double deposition of magnetic material

#115
20160245878
2016-08-25

Triaxial coil sensor and magnetic field measuring device including the same

#116
20160231392
2016-08-11

Magnetometer body and three-axis induction magnetometer using the same

#117
20160161571
2016-06-09

Fluxgate magnetic sensor readout apparatus

#118
20160161570
2016-06-09

Magnetic sensor drive circuit, magnetic sensor, current sensor, and method for driving magnetic sensor

#119
20160155935
2016-06-02

Process for NiFe fluxgate device

#120
20160154069
2016-06-02

High performance fluxgate device

#121
20160116550
2016-04-28

Integrated fluxgate magnetic sensor and excitation circuitry

#122
20160109533
2016-04-21

Inspection circuit for magnetic field detector, and inspection method for the same

#123
20160084920
2016-03-24

Method for reset and stabilization control of a magnetic sensor

#124
20150338474
2015-11-26

Integrated dual axis fluxgate sensor using double deposition of magnetic material

#125
20150316622
2015-11-05

Magnetism detection device

#126
20150285767
2015-10-08

Measurement of lay length of wire rope

#127
20150277280
2015-10-01

Differential transformer magnetic permeability sensor

#128
20150247903
2015-09-03

Linear positioning system utilizing helically polarized magnet

#129
20150212167
2015-07-30

Magnetic sensor

#130
20150212164
2015-07-30

System and method of detecting ultra weak magnetic field

#131
20150160308
2015-06-11

ORTHOGONAL FLUXGATE SENSOR

#132
20150160307
2015-06-11

ORTHOGONAL FLUXGATE SENSOR

#133
20150160306
2015-06-11

ORTHOGONAL FLUXGATE SENSOR

#134
20150085419
2015-03-26

Magnetic element control device, magnetic element control method and magnetic detection device

#135
20150077101
2015-03-19

Magnetic element control device, magnetic element control method and magnetic detection device

#136
20150070010
2015-03-12

Magnetic element control device, magnetic device control method, and magnetic detecting device

#137
20150054502
2015-02-26

Apparatus and method for reset and stabilization control of a magnetic sensor

#138
20150048820
2015-02-19

Fluxgate magnetic sensor readout apparatus

#139
20150048818
2015-02-19

Integrated fluxgate magnetic sensor and excitation circuitry

#140
20150008916
2015-01-08

Method and device for measuring a magnetic field by synchronised excitations

#141
20140327434
2014-11-06

Magnetic field sensor

#142
20140285189
2014-09-25

Fluxgate magnetic-to-digital converter with oversampling closed loop

#143
20140253113
2014-09-11

Geomagnetic sensor

#144
20140232384
2014-08-21

Magnetic core flux sensor

#145
20140232383
2014-08-21

Magnetic core flux sensor

#146
20140217533
2014-08-07

Magnetic sensor integrated in a chip for detecting magnetic fields perpendicular to the chip and manufacturing process thereof

#147
20140210463
2014-07-31

Current sensor and printed circuit board for this sensor

#148
20140200841
2014-07-17

Geomagnetic sensor calibration apparatus and method thereof

#149
20140198463
2014-07-17

Printed circuit board and magnetic field or current sensor

#150
20140184214
2014-07-03

Magnetic field sensor linearization architecture and method

#151
20140103920
2014-04-17

Magnetic field detection device and method for detecting a magnetic field

#152
20140103910
2014-04-17

Differential transformer type magnetic sensor and image forming apparatus

#153
20140097836
2014-04-10

Differential transformer type magnetic sensor and image forming apparatus

#154
20140097704
2014-04-10

Method and system for controlling the turn-on time of a device that includes a magnetic circuit

#155
20140077796
2014-03-20

Apparatus and method for measuring magnetic fields

#156
20140062464
2014-03-06

Apparatus for detecting a magnetically conductive object and position measuring system for measuring the position of a guide rod and associated position measuring method

#157
20140015523
2014-01-16

SENSOR DEVICE, A DETECTOR ARRANGEMENT AND A METHOD FOR DETECTING ARCING

#158
20140015519
2014-01-16

Fluxgate with laminar damping of the pendulum and method of assembling a fluxgate

#159
20140009143
2014-01-09

Magnetic Transducer And Current Transducer For Measuring An Electrical Current

#160
20130214777
2013-08-22

Semiconductor integrated circuit, magnetic detecting device, electronic compass, and ammeter

#161
20130207651
2013-08-15

FLUXGATE SENSOR

#162
20130154629
2013-06-20

Toroidal fluxgate current transducer

#163
20130106410
2013-05-02

Apparatus and method for reset and stabilization control of a magnetic sensor

#164
20130099778
2013-04-25

Differential transformer type magnetic sensor

#165
20130099334
2013-04-25

Z-axis semiconductor fluxgate magnetometer

#166
20130057276
2013-03-07

Printed circuit board comprising two coils

#167
20130057270
2013-03-07

Generator of a homogenous magnetic field

#168
20130049749
2013-02-28

Semiconductor fluxgate magnetometer

#169
20130015852
2013-01-17

Simple magnetometer for determining orientation of low intensity magnetic fields

#170
20120313638
2012-12-13

MAGNETIC FIELD SENSOR

#171
20120313637
2012-12-13

Current detecting apparatus

#172
20120313633
2012-12-13

PERFORMANCE-OPTIMIZED ACTIVATION OF A FLUXGATE SENSOR

#173
20120308728
2012-12-06

Magnetoresistive element and method of manufacturing the same

#174
20120163696
2012-06-28

Magnetic sensor

#175
20120151786
2012-06-21

Fluxgate sensor and electronic compass making use thereof

#176
20120130664
2012-05-24

Method for classifying electrical sheet

#177
20120126799
2012-05-24

Magnetic field sensor and method for producing a magnetic field sensor

#178
20120062209
2012-03-15

Closed-loop fluxgate current sensor

#179
20120038360
2012-02-16

Magnetic core with superparamagnetic particles for current and magnetic field sensors

#180
20120032674
2012-02-09

Current sensor

#181
20120019241
2012-01-26

Magnetic field sensor device, corresponding production method, and magnetic field measuring method

#182
20110316531
2011-12-29

DEVICE FOR MEASURING THE DIRECTION AND/OR STRENGTH OF A MAGNETIC FIELD

#183
20110241665
2011-10-06

Multi-axis fluxgate magnetic sensor

#184
20110210722
2011-09-01

Integrated magnetic sensor for detecting horizontal magnetic fields and manufacturing process thereof

#185
20110163747
2011-07-07

Housing for a magnetometer, a combination including a magnetometer within a waterproof housing, and a system and method for location and removal of unexploded ordinance underwater

#186
20110148405
2011-06-23

Magnetism measuring method and device

#187
20110140694
2011-06-16

Permanent or variable alternating magnetic field circulation sensor, and current sensor implementing such a sensor

#188
20110127999
2011-06-02

PIPELINE INSPECTION APPARATUS AND METHOD

#189
20110118999
2011-05-19

MEASUREMENT POSITION AND TIME RECORDING TYPE MAGNETOMETER AND METHOD OF MEASURING MAGNETIC FIELD USING THE SAME

#190
20110095754
2011-04-28

METHOD FOR MAKING A MAGNETIC FIELD SENSOR AND MAGNETIC FIELD SENSOR THUS OBTAINED

#191
20110074408
2011-03-31

Proton precession magnetometer sensor measurable in all direction

#192
20110050221
2011-03-03

Coil design for miniaturized fluxgate sensors

#193
20110050217
2011-03-03

Magnetic flux detection apparatus

#194
20110006779
2011-01-13

FLUX-GATE LEAKAGE CURRENT SENSOR

#195
20100271017
2010-10-28

Thin film fluxgate sensor

#196
20100231222
2010-09-16

Very low noise magnetometer

#197
20100213935
2010-08-26

MAGNETIC DETECTION ELEMENT AND DETECTION METHOD

#198
20100187916
2010-07-29

Magnetic flux measuring device and magnetic flux measuring method for stationary induction electrical apparatus, and synchronous switching control gear for circuit breaker

#199
20100161084
2010-06-24

Magnetic sensor for use with hand-held devices

#200
20100100202
2010-04-22

Method and Related Apparatus for Controlling Operating Mode of a Portable Electronic Device

#201
20100097058
2010-04-22

STRAIN-BASED CARBON NANOTUBE MAGNETOMETER

#202
20100090691
2010-04-15

Detecting device having viscoelastic magnet

#203
20090315555
2009-12-24

Power cable magnetic field sensor

#204
20090295384
2009-12-03

Magnetic field sensor and electrical current sensor therewith

#205
20090295379
2009-12-03

Electromagnetic field measuring apparatus and method therefor

#206
20090293294
2009-12-03

Sensor chip, detection device and method of manufacturing detection device

#207
20090284255
2009-11-19

Magnetic interference detection system and method

#208
20090278533
2009-11-12

Thin film 3 axis fluxgate and the implementation method thereof

#209
20090243609
2009-10-01

Magnetic sensor element and magnetic sensor using the same

#210
20090230955
2009-09-17

Orthogonal fluxgate magnetic field sensor

#211
20090195245
2009-08-06

Coupled fluxgate magnetometers for DC and time-varying target magnetic field detection

#212
20090190264
2009-07-30

Magnetoresistive element and method of manufacturing the same

#213
20090178488
2009-07-16

Mechanical amplification of small dimensional changes using bowing

#214
20090143665
2009-06-04

Magnetic detection coil and apparatus for magnetic field measurement

#215
20090072969
2009-03-19

Baggage management gate

#216
20090058410
2009-03-05

Reed relay for magnetic field measurement

#217
20090049931
2009-02-26

Magnetostrictive torque sensor

#218
20090030646
2009-01-29

AC magnetic tracking system with phase locking

#219
20090015240
2009-01-15

Detection circuit

#220
20080292044
2008-11-27

Signal detection circuit

#221
20080252289
2008-10-16

Current and magnetic field sensors, control method and magnetic core for said sensors

#222
20080246485
2008-10-09

Compact underwater electromagnetic measurement system using magnetic sensors and electrical sensors having capacitive electrodes

#223
20080094057
2008-04-24

Position measurement system employing total transmitted flux quantization

#224
20080068010
2008-03-20

FLUXGATE

#225
20080048643
2008-02-28

Current sensor with alternating magnetic excitation

#226
20080036456
2008-02-14

Device and method for detecting deformation of the viscoelastic magnet

#227
20070257669
2007-11-08

Micromagnetometer of the fluxgate type with improved excitation coil

#228
20070222441
2007-09-27

Magnetic sensor element and electronic directional measuring device

#229
20070188170
2007-08-16

Fluxgate and fluxgate magnetometers

#230
20070170916
2007-07-26

Pulsed excitation and sampled detection fluxgate type magnetometer

#231
20070151943
2007-07-05

Fluxgate sensor integrated in printed circuit board and method for manufacturing the same

#232
20070121249
2007-05-31

Electrical signal-processing device integrating a flux sensor with a flux generator in a magnetic circuit

#233
20070115585
2007-05-24

Method of manufacturing a micro flux gate sensor

#234
20070114995
2007-05-24

Magentometer circuit

#235
20070103152
2007-05-10

Digital fluxgate magnetometer

#236
20070069723
2007-03-29

Solenoid magentometer

#237
20070063699
2007-03-22

Reduced power sensing apparatus having fluxgate and control method thereof

#238
20070057670
2007-03-15

Magnetic sensor signal detection circuit using a counter

#239
20070057669
2007-03-15

Exciting coil drive circuit of magnetic sensor

#240
20060276850
2006-12-07

Detector for magnetic hazards to implanted medical device

#241
20060226826
2006-10-12

Magnetic field sensor and electrical current sensor therewith

#242
20060181272
2006-08-17

Integrated fluxgate-induction sensor

#243
20060164080
2006-07-27

Magnetic field sensor and method for operating the magnetic field sensor

#244
20060115918
2006-06-01

Method for manufacturing a magnetic field detecting element

#245
20060066292
2006-03-30

Magnetic bridge type current sensor, magnetic bridge type current detecting method, and magnetic bridge for use in that sensor and detecting method

#246
20060017435
2006-01-26

Printed circuit board having weak magnetic field sensor and method of manufacturing the same

#247
20060001422
2006-01-05

Printed circuit board with weak magnetic field sensor

#248
20050218891
2005-10-06

Digital signal conditioning solution for a magnetometer circuit

#249
20050194972
2005-09-08

Method of adjusting a fluxgate magnetometer apparatus

#250
20050172480
2005-08-11

Fabricating method for a fluxgate sensor integrated in printed circuit board

#251
20050146326
2005-07-07

Multi-conductive ferromagnetic core, variable permeability field sensor and method

#252
20050114076
2005-05-26

Fluxgate sensor for calibrating azimuth at slope and calibration method thereof

#253
20050035761
2005-02-17

Fluxgate sensor integrated in a semiconductor substrate and method for manufacturing the same

#254
20050017714
2005-01-27

Magnetic field sensor device

#255
20050006713
2005-01-13

Magnetic field detecting element and method for manufacturing the same

#256
19261530
2026-01-06

Method for estimating noise of soft magnetic core

#257
18124145
2024-09-24

Dynamic magnetic vector fluxgate magnetometer and methods of using

#258
17844101
2023-05-02

Dynamic magnetic vector fluxgate magnetometer and methods of using

#259
17120731
2022-07-26

Dynamic magnetic vector fluxgate magnetometer and methods of using

#260
16357916
2021-01-19

Self-calibrating fluxgate magnetometer and methods of using

#261
15141003
2017-02-21

Fluxgate device with low fluxgate noise

#262
14609796
2015-09-22

Injection locked nonlinear dynamic system

#263
13804097
2015-05-12

Active compensation for ambient, external magnetic fields penetrating closed loop magnetic cores particularly for a fluxgate current sensor