Rotation angle detection device
By using a spin valve type giant magnetoresistance effect film and a bridge circuit in the magnetic sensor, the difference and sum of the output voltages are calculated and corrected, and the rotation angle is obtained by inverse tangent operation, which solves the angle error caused by the manufacturing deviation of the magnetic sensor. problem and improve detection accuracy.
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Examples
example 1
[0113] Figure 16 An example of a magnetic sensor having a bridge circuit X and a bridge circuit Y including SVGMR elements is shown. The illustrated element arrangement corresponds to samples 1-3 in Table 1 described later. In the bridge circuit X, four rectangular SVGMR elements 201a to 201b are formed on the substrate, the elements 201b and 201c are connected to the power supply terminal Vcc, the elements 201a and 201d are connected to the ground terminal GND, and the elements 201a and 201b are connected to one output terminal V x1 , elements 201c and 201d are connected to the other output terminal V x2. With respect to the axis 202 parallel to the magnetization direction of the pinned layer indicated by the arrow, the long-side directions of the elements 201a to 201d are inclined by an angle θ dip-R1 ~θ dip-R4 . In the bridge circuit Y, four rectangular SVGMR elements 203a to 203d are formed on the substrate, perpendicular to the corresponding elements 201a to 201d o...
example 2
[0134] In order to increase the resistance of the SVGMR element and suppress the power consumption of the magnetic sensor, the dimension in the longitudinal direction of the element may be set to about several tens to 100 μm. As described above, when the device is made longer, the shape anisotropy of the free layer of the SVGMR film increases, and the AMR effect of the free layer cannot be ignored. Therefore, in the magnetic sensor with the same element configuration as Example 1, according to Table 3 ("+" indicates the counterclockwise angle of the element, and the brackets indicate θ dip A value of -180°) shows a change in θ dip , the Δθ when the AMR effect is added and when it is not added is obtained by simulation err . Figure 25 Indicates the result. In Equation (8), the dR ' is 22.5Ω. Sample 2-5 is an element arrangement described in Japanese Patent Application Publication No. 2003-502876 and Japanese Unexamined Patent Application Publication No. 2005-024287.
[0...
example 3
[0155] The most variable magnetic property in the SVMGR film is H int (a magnetic field acting between the fixed layer and the free layer via the intermediate layer). h int It tends to fluctuate with changes in the film thickness of the intermediate layer, the so-called "orange peel effect" caused by the surface roughness of the intermediate layer, and temperature fluctuations such as operating temperature and ambient temperature. Therefore, in order to obtain H under the most suitable component arrangement conditions (sample 3-4) int and Δθ err the relationship between Figure 26 shown in the magnetic sensor, the H int-R1 In the case of 0kA / m, 0.08kA / m, 0.16kA / m, 0.40kA / m, and 0.80kA / m, H int (H int-R5 ) Δθ when changing from -0.8kA / m to +0.8kA / m err . Figure 31 Indicates its result.
[0156] H of element 211a int-R1 = H of element 211d int-R4
[0157] Element 211b H int-R2 = H of element 211c int-R3
[0158] h int-R1 =-H int-R2
[0159] Element 213a H int...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More