JPH0552918A - Magnetic sensor, two-and three-dimensional magnetic sensors, magnetism measuring instrument, and magnetism measuring semiconductor device - Google Patents

Abstract

PURPOSE:To remove noise and direction dependency including such a case that a two- or three-dimensional sensor is constituted by arranging two magnetism-electricity converting semiconductor pulse sensors, with their directivity opposed to each other. CONSTITUTION:This magnetic sensor 6 is constituted by arranging two magnetism-electricity converting pulse sensors 1, with their directivity opposed to each other, and connected with take-out lines 2-5. A voltage is applied across the lines 2-5 through resistances R1 and R2 and, when a magnetic flux exists in the direction shown by the arrow, a voltage is generated across both ends of the resistance R1 and its frequency is decided by the density of the magnetic flux. On the other hand, no voltage is generated across both ends of the resistance R2 and its frequency is '0'. However, when the magnetic flux is in the opposite direction, the voltage is not generated across both ends of the resistance R1, but across both ends of the resistance R2 and the frequency is decided by the density of the magnetic flux. Thus the direction of the magnetic flux can be recognized from the voltages generated across the resistances R1 and R2 and the density of the magnetic flux can be decided from the frequencies. When such sensor 6 is combined by the number of two or three, a two- or three- dimensional magnetic sensor can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic sensor for measuring a magnetic field using a semiconductor sensor for converting the strength of a magnetic field into a frequency, a two-dimensional magnetic sensor, a three-dimensional magnetic sensor and a direction / strength of a magnetic field. And a method for configuring a magnetic measurement semiconductor device.

[0002]

2. Description of the Related Art A conventional magnetic sensor uses a Hall element and is used by converting magnetism into a voltage to amplify a minute signal.

When a magnetoelectric conversion semiconductor pulse sensor is used, it is used alone.

Further, in the case of the two-dimensional magnetic sensor, the three-dimensional magnetic sensor, the magnetic measuring device, and the magnetic measuring semiconductor device, the Hall element is used to amplify the output.

[0005]

However, in the above-mentioned prior art, when the Hall element is used in the magnetic sensor, the output from the magnetic sensor is small, so that the influence of noise is large. There are problems that the circuit is complicated because it cannot be used and that the voltage applied to the magnetic sensor is small. When a magnetoelectric conversion semiconductor pulse sensor is used as the magnetic sensor, the output of the magnetoelectric conversion pulse sensor 1 becomes as shown in FIG. 1B when the circuit is made as shown in FIG. Here, the magnetic flux density B is positive in the direction from the front side to the back side of the paper. The output is observed at both ends of the resistor R. As can be seen from FIG. 1 (b), although the output appears with respect to the magnetic field in the positive direction, the output frequency is 0 in the case of the negative direction, so there is a problem that measurement can be performed in only one direction.

Further, in the magnetic measuring device and the magnetic measuring semiconductor device, there are problems that the detection circuit is complicated and that an analog / digital (A / D) converter is required, resulting in high cost.

Therefore, the magnetic sensor, the two-dimensional magnetic sensor, and the three-dimensional magnetic sensor of the present invention solve the above-mentioned problems and are strong against noise, and the magnetic measurement can be performed without depending on the direction. A measuring device and a magnetic measuring semiconductor device aim at simplification of a detection circuit, cost reduction, and size reduction of the device.

[0008]

[Means for Solving the Problems]

(1) The magnetic sensor of the present invention is characterized in that two magnetoelectric conversion semiconductor pulse sensors having a directivity by converting the strength of a magnetic field into a frequency are arranged so that the directivities are opposite to each other.

(2) The two-dimensional magnetic sensor of the present invention for measuring two dimensions is characterized by having the above-mentioned magnetoelectric conversion semiconductor pulse sensor.

(3) The three-dimensional magnetic sensor of the present invention is characterized by having at least one of the magnetoelectric conversion semiconductor pulse sensor, the magnetic sensor, or the two-dimensional magnetic sensor.

(4) The magnetic measuring device of the present invention comprises a sensor section having at least one or more magnetic sensors according to (1) to (3), a frequency detecting section for detecting a frequency from a signal from the sensor section, It is characterized by having a magnetic calculation unit for calculating the direction and strength of the magnetic field from the frequency obtained by the frequency detection unit.

(5) In the magnetic measurement semiconductor device of the present invention, at least two or more magnetoelectric conversion semiconductor pulse sensors that convert magnetic field strength into frequency and have directivity are formed on the same semiconductor substrate, or A sensor unit having at least one magnetoelectric conversion semiconductor pulse sensor, a frequency detecting unit for detecting a frequency from a signal from the sensor unit, and a direction and strength of a magnetic field based on the frequency obtained by the frequency detecting unit. Is characterized in that at least one or more of the magnetic calculation sections for calculating are formed on the same semiconductor substrate.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 (a) is a diagram of an embodiment showing the structure of a magnetic sensor according to claim 1, FIG. 2 (b) is a diagram of an embodiment in which a circuit is connected to the magnetic sensor, and 1 is a diagram. Magnetoelectric conversion pulse sensor typified by 1 which converts magnetism to frequency and has directivity, 2 to 5 are extraction lines A, extraction lines B, extraction lines C, extraction lines D, 6 are magnetic sensors, 7 ... Reference numeral 8 is resistors R1 and R2. When a voltage is applied as shown in FIG. 2B and a magnetic flux density B is applied as shown in FIG. 2A (the magnetic field is in the direction from the front side to the back side of the paper), R
A voltage is generated across 1 and its frequency is determined by the magnetic flux density B. In this case, no voltage is generated across R2 and the frequency is zero. However, the magnetic flux density B is shown in FIG.
When it is in the opposite direction, that is, from the back of the paper to the front, R
No voltage is generated at both ends of 1, and at this time a voltage is generated at R2 and the frequency is determined by the magnetic flux density B. From the above, when a frequency change occurs in R1, the magnetic field in the positive direction (the positive direction is the magnetic field from the front side to the back side of the paper, the direction of the magnetic flux density B shown in FIG. 2A), and the frequency changes in R2. When it is generated, it is known that the magnetic field is in the negative direction, and the strength of the magnetic field is determined by the frequency of each. Therefore, it becomes a magnetic sensor for examining the direction and strength of the magnetic field.

FIG. 3 (a) is an embodiment of the two-dimensional magnetic sensor according to claim 2, wherein each magnetic sensor 6 in FIG. 3 (a) has a direction of an arrow written therein. The magnetic sensor according to claim 1 that operates with the positive sign, and has a configuration as shown in FIG. Since the two magnetic sensors are orthogonal to each other, when observing the magnetic flux density B as shown in FIG. 3 (b), by the magnetic sensor on the upper side in FIG. Bx is detected by the magnetic sensor on the side.

Then, B can be obtained by B × B = Bx × Bx + By × By tan θ = Bx / By.

FIG. 4 is a diagram of an embodiment showing the outline of the three-dimensional magnetic sensor according to claim 3, wherein when observing the magnetic flux density B, the characteristics of the directions of the arrows in the X, Y and Z axes are claimed. 1
When the described magnetic sensors are arranged, each magnetic sensor observes the component (Bx · By · Bz) of the magnetic flux density B. Therefore, from this observation value, B × B = Bx × Bx + By × By + Bz × Bz COSφ = Bz / B tan θ = Bx / By, which is calculated from this formula.

FIG. 5 is a diagram showing one embodiment of a three-dimensional magnetic sensor which is a more specific version of FIG.
Reference numerals 1 to 13 are an X-direction magnetic sensor, a Y-direction magnetic sensor, and a Z-direction magnetic sensor, respectively. Each magnetic sensor is Bx ・ By ・ B according to the principle shown in FIG.
z can be observed, and the magnetic field can be calculated.

FIG. 6 is a basic block diagram of the magnetic measuring device according to claim 4, wherein 21 is a sensor section using a magnetoelectric conversion pulse sensor, 22 is a frequency detecting section, and 23 is a magnetic field from the obtained data. A magnetic calculation unit for calculation, 24 is a voltage signal from the sensor unit, and 25 is a frequency signal. The magnetic field can be measured by detecting the frequency by counting the voltage signal that oscillates at the frequency determined by the magnetic flux density in the sensor unit by the frequency detecting unit and calculating based on the frequency.

FIG. 7 is a diagram of an embodiment of the magnetic measuring apparatus according to the present invention, in which 31 is an analog switch, 32 is a counter, 33 is a CPU, 34 is an analog switch switching signal, and 35 is a count start / reset signal. , 36 is a select data signal, 37 is a count data signal, 38
Is the answer signal. Analog switch 31 to CPU
Controlled by 33, one signal is transmitted to the counter 32 for the time Ts. Counter 32 has select signal 36
To count. Then, the count number within the Ts time is output as a count data signal, and the frequency f is calculated by the CPU 33 as f = N / Ts by Ts and the count number N of the count signal. Then, the magnetic flux density B can be determined by the obtained frequency. The above result is output to the answer signal 38.

FIG. 8 is an overall block diagram of the magnetic measurement semiconductor device according to the fifth aspect. 41 is a semiconductor substrate. Sensor unit 21, frequency detection unit 22, magnetic calculation unit 2
3 is an example in which 3 is formed on one semiconductor substrate.

FIG. 9 is a cross-sectional view of a semiconductor substrate showing a specific example of the sensor portion of FIG. Reference numeral 51 is a semiconductor substrate (wafer), and 52 is a takeout wiring.

Further, there is an example in which a three-dimensional magnetic sensor is formed on the same substrate as in the example of FIG. 5 and an example in which it is formed on one semiconductor substrate of the example of FIG.

[0023]

According to the invention as described above, the characteristic of a magnetic sensor has directivity, but by using two in combination, the directivity can be eliminated and the direction and strength of the magnetic field can be measured. In the case of a two-dimensional and three-dimensional magnetic sensor, it is possible to measure the two-dimensional magnetic strength and direction and the three-dimensional magnetic strength and direction by configuring the two-dimensional and three-dimensional magnetic sensors at right angles.

Further, when the magnetoelectric conversion semiconductor pulse sensor is used in the magnetic measuring device, there is no need to amplify the signal or perform analog-digital conversion as in the case of using the Hall element, and the magnetic flux density can be measured by using the counter. By using a magnetic measurement semiconductor device, it is possible to produce a space-saving, low-cost, high-precision measurement device.

Further, since the pulse signal can be used as it is as the input of the counter, there is an effect that it becomes very strong against noise.

[Brief description of drawings]

FIG. 1 is a diagram showing a usage example and output characteristics of a magnetoelectric conversion element.

FIG. 2 is a diagram of an embodiment of a magnetic sensor of the present invention.

FIG. 3 is a diagram of an embodiment of a two-dimensional magnetic sensor of the present invention.

FIG. 4 is a diagram of an embodiment of a three-dimensional magnetic sensor of the present invention.

FIG. 5 is a diagram of an embodiment of a three-dimensional magnetic sensor of the present invention.

FIG. 6 is a diagram of an embodiment of a magnetic measurement apparatus of the present invention.

FIG. 7 is a diagram of an embodiment of a magnetic measurement apparatus of the present invention.

FIG. 8 is a diagram of an embodiment of a magnetic measurement semiconductor device of the present invention.

FIG. 9 is a diagram of an embodiment of a magnetic measurement semiconductor device of the present invention.

[Explanation of symbols]

 1 Magnetoelectric conversion pulse sensor 2 Extraction line A 3 Extraction line B 4 Extraction line C 5 Extraction line D 6 Magnetic sensor 7 Resistor R1 8 Resistor R2 10, 41, 51 Semiconductor substrate 11 X direction magnetic sensor 12 Y direction magnetic sensor 13 Z direction Magnetic sensor 21 Sensor part 22 Frequency detection part 23 Magnetic calculation part 24 Voltage signal 25 Frequency signal 31 Analog switch 32 Counter 33 CPU 34 Analog switch switching signal 35 Count start / reset signal 36 Select data signal 37 Count data signal 38 Answer signal 52 Extraction wiring

Claims (5)

[Claims] 1. A magnetic sensor for measuring magnetism, comprising:
A magnetic sensor comprising: two magnetic-electric conversion semiconductor pulse sensors, which have a directivity by converting the strength of a magnetic field into a frequency, arranged so that the directivities are opposite to each other. 2. A two-dimensional magnetic sensor for measuring a two-dimensional magnetic field, comprising the above-mentioned magnetoelectric conversion semiconductor pulse sensor. 3. A magnetic sensor for measuring a three-dimensional magnetic field, comprising at least one of the above-mentioned magnetoelectric conversion semiconductor pulse sensor, the magnetic sensor according to claim 1, or the magnetic sensor according to claim 2.
Dimensional magnetic sensor. 4. A magnetic measuring device for measuring the direction / strength of a magnetic field, comprising a sensor unit having at least one magnetic sensor according to claim 1 or 2 and detecting a frequency from a signal from the sensor unit. A magnetic measurement device comprising: a frequency detection unit; and a magnetic calculation unit that calculates the direction and strength of a magnetic field from the frequency obtained by the frequency detection unit. 5. In a magnetic measurement semiconductor device for measuring the direction and strength of a magnetic field, at least two or more magnetoelectric conversion semiconductor pulse sensors for converting magnetic field strength into frequency and having directivity are formed on the same semiconductor substrate. Or a sensor section in which the magnetoelectric conversion semiconductor pulse sensor is composed of at least one, a frequency detecting section for detecting a frequency from a signal from the sensor section, and a magnetic field based on the frequency obtained by the frequency detecting section. 2. A magnetic measurement semiconductor device, wherein at least one or more magnetic calculation units for calculating the direction and strength of a magnetic field are formed on the same semiconductor substrate.