WO2014115765A1 - 磁気検出装置 - Google Patents
磁気検出装置 Download PDFInfo
- Publication number
- WO2014115765A1 WO2014115765A1 PCT/JP2014/051261 JP2014051261W WO2014115765A1 WO 2014115765 A1 WO2014115765 A1 WO 2014115765A1 JP 2014051261 W JP2014051261 W JP 2014051261W WO 2014115765 A1 WO2014115765 A1 WO 2014115765A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- magnetic
- pulse
- electronic switch
- detection coil
- voltage
- Prior art date
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
- G01R33/09—Magnetoresistive devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/0023—Electronic aspects, e.g. circuits for stimulation, evaluation, control; Treating the measured signals; calibration
Definitions
- the present invention relates to a magnetic detection device capable of high sensitivity, low noise, and power saving.
- Magnetic detectors are used for foreign object detection, geomagnetism detection, posture grasp, etc. Recently, ultra-small magnetic detection devices are mounted on mobile terminals such as mobile phones and smartphones.
- a typical example of such a magnetic detection apparatus is a MEMS (Micro Electro Mechanical Systems) pulse-driven detection coil magnetic impedance sensor.
- the magneto-impedance sensor is a magneto-impedance effect (MI effect) in which when a high-frequency current is passed through a magnetosensitive wire (particularly an amorphous wire) made of a CoFeSiB alloy or the like, the impedance changes according to the external magnetic field due to the skin effect. ).
- the detection coil type is a method in which the impedance change is detected by an induced voltage generated in a detection coil wound around the magnetic sensing wire.
- the pulse drive type is a type in which a pulse current is supplied as a high-frequency current to be supplied to the magnetosensitive wire.
- MI sensor not only the magnetic impedance sensor but also the pulse drive type detection coil type magnetic impedance sensor will be simply referred to as “MI sensor” as appropriate. The description relating to such an MI sensor can be found in the following patent document, for example.
- the detection coil is directly connected to the hold capacitor via the electronic switch.
- the current flowing through the circuit including the detection coil by the induced voltage is directly charged to the hold capacitor, and the voltage across the hold capacitor (hold voltage) is amplified to be the output voltage.
- the voltage drop (IR drop) caused by the current (I) flowing through the circuit including the detection coil becomes larger based on the induced voltage than the increase in the induced voltage generated in the detection coil, and the hold voltage is reduced. A phenomenon occurs. Therefore, even if the fine pitch is made as in the conventional analog signal detection circuit, the high sensitivity of the MI sensor cannot be achieved.
- the capacitance of the hold capacitor mounted on the currently sold MI sensor is 6 pF. If this can be increased to at least about 10 pF, the noise can be reduced by about 10 to 30%. However, if the capacitance is increased with the conventional analog type signal detection circuit, the hold capacitor is not sufficiently charged within a very short time corresponding to the pulse current, and the hold voltage is lowered. Sensitivity is reduced.
- the drive current supplied to the magnetosensitive wire for example, narrowing the pulse width or reducing the number of pulses.
- the hold capacitor is still insufficiently charged, and it is difficult to save power while maintaining the sensitivity of the MI sensor.
- the present invention has been made in view of such circumstances, and an object thereof is to provide a magnetic detection device including a new type of signal detection circuit capable of achieving high sensitivity, low noise, power saving, and the like. To do.
- the present inventor has made a buffer circuit interposed between the detection coil and the hold capacitor of the pulse-driven detection coil type MI sensor, and only the detection coil side circuit.
- the hold capacitor side circuit By increasing the impedance of the hold capacitor side circuit, it has been devised that an output signal voltage following the input signal voltage of a high frequency (converted frequency) generated on the detection coil side is generated in the hold capacitor side circuit.
- the digital signal detection circuit that transmits the signal voltage from the detection coil to the hold capacitor via the buffer circuit in this way, it is possible to greatly improve the sensitivity and noise reduction of the MI sensor. I found it.
- the present invention described below has been completed.
- a magnetic detection device includes a magnetic sensing section including a magnetic sensing body and a detection coil wound around the magnetic sensing body, a pulse transmission circuit section for transmitting a pulse current to be supplied to the magnetic sensing body, and the pulse
- a sample-and-hold circuit unit comprising an electronic switch that is turned on and off at a timing according to the transmission of current, a hold capacitor that is charged when the electronic switch is turned on, and a hold voltage that is held by the hold capacitor when the electronic switch is turned off
- a magnetic detection device comprising an amplification circuit unit for amplifying and outputting Further, an input side is connected to the detection coil side and an output side is connected to the electronic switch side, and an output signal voltage that follows an input signal voltage composed of a pulsed induced voltage generated in the detection coil is generated.
- a buffer circuit unit for transmitting a signal voltage from the input side to the output side is provided.
- the input side (detection coil side) of the buffer circuit unit according to the present invention has high impedance, even if an induced voltage is generated in the detection coil, almost no current flows on the detection coil side. For this reason, even if the resistance value of the detection coil increases due to fine pitch, etc., there is almost no voltage drop (even if a slight voltage drop occurs), and the high induced voltage generated in the detection coil is almost unchanged as the input signal voltage. Is input to the buffer circuit section.
- the output side of the buffer circuit itself is generally low impedance.
- a hold capacitor (several to several tens of pF level) having a very small capacitance is connected to the output side.
- the capacitive reactance (1 / j ⁇ C, j: imaginary unit, ⁇ : angular frequency of the transmitted signal) of the circuit formed on the output side of the buffer circuit unit becomes very large, As a result, the impedance of the circuit formed on the output side of the buffer circuit section also becomes very large.
- the signal detection circuit digital type signal detection circuit
- a buffer circuit having a high frequency band of about 100 MHz has a capability of transferring a pulse voltage having a conversion frequency of about 3 GHz from the input side to the output side.
- a high-frequency signal is transmitted, if a delay of about 1 ns (10 ⁇ 9 seconds) occurs in the signal voltage transmitted between the input side and the output side, transmission of the high-frequency signal corresponding to 0.2 GHz is performed. It becomes difficult.
- a pulse signal is transmitted, even if a delay of about 1 ns occurs in the pulse voltage transmitted between the input side and the output side, the pulse voltage is transmitted and the delay is fatal. This is not a problem.
- the present invention has been embodied and completed based on the idea and discovery based on such a pulse frequency band.
- a current flows from the output side of the buffer circuit section to the hold capacitor in an instant immediately after turning on the electronic switch, and the hold capacitor is charged. Except for this moment, when the electronic switch is in the ON state, the voltage across the hold capacitor can change according to the induced voltage generated in the detection coil. When the electronic switch is turned off in the vicinity of the peak of the induced voltage generated in the detection coil, the voltage across the hold capacitor at that time is held as the hold voltage.
- the hold capacitor according to the present invention is not directly charged by the current flowing through the detection coil based on the induced voltage, but is charged by the current supplied from the buffer circuit unit. As long as the circuit is maintained, the capacitance of the hold capacitor can be increased as compared with the conventional case. As a result, in the magnetic detection device of the present invention, it is possible to reduce noise by increasing the capacitance of the hold capacitor while maintaining and improving sensitivity and the like.
- the conversion frequency of the pulse current according to the present invention is preferably 0.3 to 3 GHz, and more preferably 0.4 to 2 GHz.
- the pulse frequency band that is the frequency band of the pulsed signal voltage transmitted through the buffer circuit unit is also within the range corresponding to the converted frequency (specifically Is preferably 0.3 to 3 GHz).
- the hold capacitor has a capacitance of 10 to 100 pF, more preferably 12 to 30 pF. If the capacitance is too small, sufficient noise reduction cannot be achieved. If the capacitance is excessive, the impedance formed on the output side of the buffer circuit portion becomes small, making it difficult to form the digital signal detection circuit described above, leading to a decrease in the pulse frequency band.
- x to y in this specification includes a lower limit value x and an upper limit value y.
- a range such as “a to b” can be newly established with any numerical value included in various numerical values or numerical ranges described in the present specification as a new lower limit value or upper limit value.
- the magnetic sensing part is composed of a magnetic sensing body and a detection coil.
- their specific form, material, etc. are not limited.
- the magnetic sensitive body is made of a magnetic sensitive wire made of an amorphous soft magnetic alloy having zero magnetostriction, it is easy to realize miniaturization and high sensitivity.
- MI element magneto-impedance element
- one MI element is provided for each external magnetism detection direction (coordinate axis direction) that is basically a detection target. Therefore, for example, when detecting a magnetic component in each axial direction in a three-axis orthogonal coordinate system, three MI elements in which magnetosensitive wires are arranged in parallel in the x-axis direction, the y-axis direction, and the z-axis direction are necessary. It becomes. However, as disclosed in WO 2005/19851, a part of the MI element can be omitted.
- the magnetic detection device of the present invention may, for example, detect only the magnetic components in the specific axis direction or detect independent three-axis direction magnetic components. You may do it.
- the magnetic detection device of the present invention may be used for any purpose, for example, a mobile phone, a smartphone, a tablet terminal, which requires detection of orientation, orientation, etc., and is required to be downsized, highly sensitive, power-saving, etc. It is built into electronic devices such as car navigation systems, digital cameras, 3D mice, motion capture, and remote controller controllers for games.
- FIG. 1 shows a circuit diagram of a magnetic detection device 1 according to an embodiment of the present invention.
- the magnetic detection device 1 includes a magnetic sensing unit 10, a pulse transmission circuit unit 20, a buffer circuit unit 30, a sample hold circuit unit 40, and an amplification circuit unit 50.
- the magnetosensitive part 10 is composed of an MI element having a magnetosensitive wire 11 (magnetic body) made of an amorphous wire of a CoFeSiB alloy and a detection coil 12 wound around the magnetosensitive wire 11.
- a pulse current which will be described later
- a pulsed magnetic field is generated in the circumferential direction of the magnetic sensing wire 11, and a rising portion or falling portion of the pulse current (a portion where di / dt changes greatly).
- a pulse-like induced voltage corresponding to is also generated in the detection coil 12.
- the magnetic field generated around the magnetic sensing wire 11 changes under the influence of external magnetism, and the change appears as a change in the induced voltage detected by the detection coil 12.
- the external magnetism generated around the magnetosensitive wire 11 can be accurately grasped.
- the pulse transmission circuit unit 20 includes a pulse transmitter 21 and supplies a predetermined pulse current to the magnetosensitive wire 11. Further, the pulse transmission circuit unit 20 supplies a control signal (voltage) substantially synchronized with the timing of transmitting the pulse current to an electronic switch 41 described later.
- the buffer circuit unit 30 includes an amplifier 31 and is a feedback (negative feedback) circuit.
- the impedance of the input side of the amplifier 31 is substantially infinite. For this reason, the induced voltage generated in the detection coil 12 hardly enters a voltage drop and is input to the amplifier 31 almost as it is.
- the impedance of the output side of the amplifier 31 is small, the impedance of a circuit connected to the output side is very large because the capacitance of a hold capacitor 42 described later is very small.
- the sample and hold circuit unit 40 includes an electronic switch 41 and a hold capacitor 42.
- the electronic switch 41 opens and closes based on a control signal from the pulse transmitter 21. For example, the electronic switch 41 is turned on for a predetermined time when the pulse current rises, and is turned off so that the induced voltage has a peak value. When the electronic switch is turned off, the voltage generated at both ends of the hold capacitor 42 is held as a hold voltage.
- the amplification circuit unit 50 includes a differential amplifier 51, and amplifies and outputs the hold voltage of the hold capacitor 42 with respect to the ground voltage.
- a high frequency filter circuit may be provided on the input side of the amplifier circuit unit 50, or a low frequency filter circuit may be provided on the output side thereof.
- test An example of measuring the sensitivity and noise of a magnetic detection device (hereinafter referred to as an example) provided with a buffer circuit unit as described above and a magnetic detection device (hereinafter referred to as a comparative example) not provided with the buffer circuit unit is shown below. .
- an amorphous wire made of a CoFeSiB alloy having a diameter of 10 ⁇ m and a length of 0.6 mm was used as the magnetosensitive wire.
- the pulse current was a rectangular wave with a pulse width of 10 ns, a rise time or a fall time of 0.5 ns, and a current value of 150 mA, and the pulse frequency was 50 Hz.
- the conversion frequency of this pulse current (frequency when 4 ⁇ t shown in FIG. 2B is one cycle) is 500 MHz (0.5 GHz) as can be seen from the rise time or fall time.
- the sensitivity of the comparative example was 16 mV / G. Rose significantly to 26 mV / G. Under the same conditions, the noise of the comparative example was 2 mG, but the sensitivity of the example was significantly reduced to 1 mG.
Landscapes
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Measuring Magnetic Variables (AREA)
- Hall/Mr Elements (AREA)
Abstract
Description
本発明の磁気検出装置は、感磁体と該感磁体の周囲に巻回された検出コイルとからなる感磁部と、該感磁体へ供給するパルス電流を発信するパルス発信回路部と、該パルス電流の発信に応じたタイミングでON-OFFする電子スイッチと該電子スイッチのON時に充電されるホールドコンデンサとからなるサンプルホールド回路部と、該電子スイッチのOFF時に該ホールドコンデンサにより保持されたホールド電圧を増幅して出力する増幅回路部とを備えた磁気検出装置であって、
さらに、前記検出コイル側に入力側が接続されると共に前記電子スイッチ側に出力側が接続されており、該検出コイルに生じたパルス状の誘起電圧からなる入力信号電圧に追従した出力信号電圧を生じて、該入力側から該出力側へ信号電圧を伝達するバッファー回路部を設けたことを特徴とする。
特に断らない限り本明細書でいう「x~y」は下限値xおよび上限値yを含む。本明細書に記載した種々の数値または数値範囲に含まれる任意の数値を新たな下限値または上限値として「a~b」のような範囲を新設し得る。
感磁部は感磁体と検出コイルとからなるが、本発明ではそれらの具体的な形態や材質等は問わない。もっとも感磁体が、零磁歪となる軟磁性合金のアモルファスからなる感磁ワイヤからなると、小型化と高感度化を実現し易く好適である。このような感磁部を構成する磁気インピーダンス素子(MI素子)に関する出願は多数されており、例えば、WO2005/19851号公報、WO2009/119081号公報、日本特許4655247号公報などに詳しく記載されている。
本発明の磁気検出装置は、その用途を問わないが、例えば、方位や姿勢等の検知を必要とし、小型化、高感度化、省電力化等が要求される携帯電話、スマートフォン、タブレット端末、カーナビゲーション、デジタルカメラ、三次元マウス、モーションキャプチャ、ゲーム用リモコンコンコントローラ等の電子器機に組み込まれる。
上述したようなバッファー回路部を設けた磁気検出装置(以下、実施例という。)とそれを設けない磁気検出装置(以下、比較例という。)とによる感度およびノイズを測定した一例を以下に示す。この際、感磁ワイヤには、直径:10μm、長さ:0.6mmのCoFeSiB系合金からなるアモルファスワイヤを用いた。パルス電流は、パルス幅:10ns、立上り時間若しくは立下り時間:0.5ns、電流値:150mAの矩形波とし、パルス周波数は50Hzとした。ちなみに、このパルス電流の換算周波数(図2Bに示す4Δtを1周期としたときの周波数)は、上記の立上り時間若しくは立下り時間からわかるように500MHz(0.5GHz)となる。
20 パルス発信回路部
30 バッファー回路部
40 サンプルホールド回路部
50 増幅回路部
Claims (4)
- 感磁体と該感磁体の周囲に巻回された検出コイルとからなる感磁部と、
該感磁体へ供給するパルス電流を発信するパルス発信回路部と、
該パルス電流の発信に応じたタイミングでON-OFFする電子スイッチと該電子スイッチのON時に充電されるホールドコンデンサとからなるサンプルホールド回路部と、
該電子スイッチのOFF時に該ホールドコンデンサにより保持されたホールド電圧を増幅して出力する増幅回路部とを備えた磁気検出装置であって、
さらに、前記検出コイル側に入力側が接続されると共に前記電子スイッチ側に出力側が接続されており、該検出コイルに生じたパルス状の誘起電圧からなる入力信号電圧に追従した出力信号電圧を生じて、該入力側から該出力側へ信号電圧を伝達するバッファー回路部を設けたことを特徴とする磁気検出装置。 - 前記パルス電流の換算周波数は0.3~3GHzであり、
前記バッファー回路部を伝達するパルス状の信号電圧の周波数帯域であるパルス周波数帯域内に該換算周波数が含まれる請求項1に記載の磁気検出装置。 - 前記ホールドコンデンサは、静電容量が10~100pFである請求項1または2に記載の磁気検出装置。
- 前記感磁体は、軟磁性合金のアモルファスからなる感磁ワイヤである請求項1~3のいずれかに記載の磁気検出装置。
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/763,221 US9404980B2 (en) | 2013-01-25 | 2014-01-22 | Magnetometers |
JP2014509967A JP5678358B2 (ja) | 2013-01-25 | 2014-01-22 | 磁気検出装置 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2013-012698 | 2013-01-25 | ||
JP2013012698 | 2013-01-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2014115765A1 true WO2014115765A1 (ja) | 2014-07-31 |
Family
ID=51227556
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2014/051261 WO2014115765A1 (ja) | 2013-01-25 | 2014-01-22 | 磁気検出装置 |
Country Status (3)
Country | Link |
---|---|
US (1) | US9404980B2 (ja) |
JP (1) | JP5678358B2 (ja) |
WO (1) | WO2014115765A1 (ja) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20170176547A1 (en) * | 2015-12-18 | 2017-06-22 | Magnedesign Corporation | Magnetometer with a differential type integrated circuit |
US9857436B2 (en) | 2015-02-16 | 2018-01-02 | Magnedesign Corporation | High sensitive micro sized magnetometer |
WO2018230262A1 (ja) * | 2017-06-16 | 2018-12-20 | 朝日インテック株式会社 | 超高感度マイクロ磁気センサ |
JP2020183878A (ja) * | 2019-04-30 | 2020-11-12 | マグネデザイン株式会社 | 高速高感度磁気センサ |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9607907B2 (en) * | 2014-12-01 | 2017-03-28 | Industrial Technology Research Institute | Electric-programmable magnetic module and picking-up and placement process for electronic devices |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000258517A (ja) * | 1999-03-10 | 2000-09-22 | Japan Science & Technology Corp | 磁気インピーダンス効果マイクロ磁気センサ |
JP2003329745A (ja) * | 2002-05-08 | 2003-11-19 | Canon Electronics Inc | 磁界強度検出装置 |
JP2010256109A (ja) * | 2009-04-23 | 2010-11-11 | Aichi Steel Works Ltd | 超高感度マグネトインピーダンスセンサ |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0762709B2 (ja) * | 1986-12-05 | 1995-07-05 | シチズン時計株式会社 | 方位センサ付き電子機器 |
JPH1164475A (ja) * | 1997-08-15 | 1999-03-05 | Alps Electric Co Ltd | フラックスゲートセンサー用の磁心及びフラックスゲートセンサー用の磁心の製造方法 |
JP2001221839A (ja) * | 2000-02-09 | 2001-08-17 | Tdk Corp | 磁界センサ |
AU2003211249A1 (en) * | 2002-02-19 | 2003-09-09 | Aichi Steel Corporation | Magnet with electromagnetic coil/impedance/sensor element |
KR100666292B1 (ko) | 2003-08-25 | 2007-01-11 | 아이치 세이코우 가부시키가이샤 | 자기 센서 |
JP5116433B2 (ja) | 2006-10-25 | 2013-01-09 | 愛知製鋼株式会社 | 変動磁場検出用磁気検出器 |
JP4961623B2 (ja) | 2007-07-23 | 2012-06-27 | アイチ・マイクロ・インテリジェント株式会社 | 磁気センサ |
JP2009145074A (ja) * | 2007-12-11 | 2009-07-02 | Fujikura Ltd | フラックスゲートセンサおよびその製造方法 |
JP4650591B2 (ja) | 2008-03-28 | 2011-03-16 | 愛知製鋼株式会社 | 感磁ワイヤ、マグネトインピーダンス素子およびマグネトインピーダンスセンサ |
US8063634B2 (en) * | 2008-07-31 | 2011-11-22 | Allegro Microsystems, Inc. | Electronic circuit and method for resetting a magnetoresistance element |
-
2014
- 2014-01-22 WO PCT/JP2014/051261 patent/WO2014115765A1/ja active Application Filing
- 2014-01-22 US US14/763,221 patent/US9404980B2/en active Active
- 2014-01-22 JP JP2014509967A patent/JP5678358B2/ja active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000258517A (ja) * | 1999-03-10 | 2000-09-22 | Japan Science & Technology Corp | 磁気インピーダンス効果マイクロ磁気センサ |
JP2003329745A (ja) * | 2002-05-08 | 2003-11-19 | Canon Electronics Inc | 磁界強度検出装置 |
JP2010256109A (ja) * | 2009-04-23 | 2010-11-11 | Aichi Steel Works Ltd | 超高感度マグネトインピーダンスセンサ |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9857436B2 (en) | 2015-02-16 | 2018-01-02 | Magnedesign Corporation | High sensitive micro sized magnetometer |
US20170176547A1 (en) * | 2015-12-18 | 2017-06-22 | Magnedesign Corporation | Magnetometer with a differential type integrated circuit |
US10473732B2 (en) * | 2015-12-18 | 2019-11-12 | Magnedesign Corporation | Magnetometer with a differential-type integrated circuit for MI sensor and GSR |
WO2018230262A1 (ja) * | 2017-06-16 | 2018-12-20 | 朝日インテック株式会社 | 超高感度マイクロ磁気センサ |
JP2019002851A (ja) * | 2017-06-16 | 2019-01-10 | 朝日インテック株式会社 | 超高感度マイクロ磁気センサ |
JP2020183878A (ja) * | 2019-04-30 | 2020-11-12 | マグネデザイン株式会社 | 高速高感度磁気センサ |
Also Published As
Publication number | Publication date |
---|---|
JPWO2014115765A1 (ja) | 2017-01-26 |
US20150355294A1 (en) | 2015-12-10 |
US9404980B2 (en) | 2016-08-02 |
JP5678358B2 (ja) | 2015-03-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5678358B2 (ja) | 磁気検出装置 | |
CN103492895B (zh) | 磁检测装置 | |
US20160116551A1 (en) | Magneto-impedance sensor element with electromagnetic coil and magneto-impedance sensor with electromagnetic coil | |
US9442143B2 (en) | Capacitive proximity sensor as well as method for capacitive approximation detection | |
US10473732B2 (en) | Magnetometer with a differential-type integrated circuit for MI sensor and GSR | |
JP6348573B2 (ja) | 圧力検出装置 | |
WO2018225454A1 (ja) | Gsrセンサ素子 | |
JP6240994B1 (ja) | 3次元磁界検出素子および3次元磁界検出装置 | |
JP6474883B2 (ja) | 磁気抵抗オーディオピックアップ | |
EP2878945A1 (en) | Conductive foreign material detecting apparatus | |
JP5116433B2 (ja) | 変動磁場検出用磁気検出器 | |
JP2015090351A5 (ja) | ||
US9461635B2 (en) | Signal processing circuit | |
AU2018284779B2 (en) | Ultra high-sensitivity micro magnetic sensor | |
MD3961G2 (ro) | Dispozitiv pentru măsurarea rezistenţei liniare a microconductorului cu izolaţie de sticlă în proces de turnare | |
CN106788327B (zh) | 一种接触与非接触检测兼用的传感器电路 | |
JP6414498B2 (ja) | 差動型磁気センサ | |
JP5948105B2 (ja) | 信号検出回路、及び電子方位計、電流センサ | |
JP6422012B2 (ja) | 磁気検出装置 | |
JP2007085824A (ja) | 磁気検出装置 | |
JP5758229B2 (ja) | 磁界検出装置 | |
US20140152293A1 (en) | Sensing circuit | |
JP2020183878A (ja) | 高速高感度磁気センサ | |
JP3197412U (ja) | 位置検知装置および無線電力伝送装置 | |
WO2013014321A3 (es) | Métodos y sistemas para dispositivos mems (sistemas microelectromecánicos) cmos (semiconductor complementario de óxido metálico) que incluyen una brújula de múltiples hilos |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
ENP | Entry into the national phase |
Ref document number: 2014509967 Country of ref document: JP Kind code of ref document: A |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 14743506 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 14763221 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 14743506 Country of ref document: EP Kind code of ref document: A1 |