JPH09297038A - Hall element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the detection sensitivity while preventing scaling up. SOLUTION: This element is provided with a resin mold 4 around a via chip 2 and its periphery, and it is of surface mounting type where leads 8a and 8b, etc., are led from the mold 4. The plane of the chip 2 and the end part of the lead 8 are arranged in a manner that they are at a right angle against the fitting surface of a printed board 5. By such a structure, after the chip 2 is mounted on the board 5, it becomes orthogonal to the fitting surface of the board 5, that is, it faces a magnet, so that the density of magnetic flux from the magnet can be made high and the sensitivity of magnetism of a Hall element be also improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor device, and more particularly to a sensor device having a vertical Hall element.

[0002]

2. Description of the Related Art A surface mount semiconductor Hall element (or Hall sensor) is used for detecting the position of a motor (specifically, a brushless motor) serving as a drive source of a drive mechanism of equipment such as a compact disk and a floppy disk. Is used as a magnetic sensor.

FIG. 4 shows a conventional semiconductor Hall element (hereinafter,
A plan view showing the configuration of the main part of the "Hall element",
FIG. 5 is a plan view showing a positional relationship between a chip portion and a magnet in a conventional Hall element, and FIG. 6 is a front view showing a mounted state of the conventional Hall element. As shown in FIG. 4, in the Hall element, bar-shaped lead frames 1b, 1c, 1d are arranged in parallel with each other with respect to the L-shaped lead frame 1a,
A bare chip 2 is mounted at the center of the tip of an L-shaped lead frame 1a, and the electrode portion of the bare chip 2 and each of the lead frames 1a, 1b, 1c, 1d are connected by a gold wire 3 (bonding wire). ing. Furthermore,
As shown in FIG. 5, the mounting portion of the bare chip 2 is sealed by the resin mold 4. After that, the excess portion of the lead frame is cut and removed, and the portion left on the resin mold 4 side is bent or the like.

When the Hall element having the above-described structure is mounted on a device, the Hall element is mounted on the printed circuit board 5 by using solder or the like, as shown in FIGS.
In this way, the bare chip 2 is a horizontal Hall sensor arranged horizontally with respect to the printed circuit board 5. The bare chip 2 in the hall element on the printed circuit board 5
A magnet 6 (which is one component forming the magnet rotor of the motor and rotates together with the rotating body of the motor) is arranged at a distance L from the side surface of the motor. Magnetic field 7 generated from magnet 6
Is detected by the bare chip 2 as shown in FIG. 6, and an output voltage corresponding to the strength of the magnetic field 7 is generated from the output terminal of the bare chip 2.

[0005]

However, according to the conventional Hall element, the distance L between the magnet and the bare chip tends to be long, and there is a limit to downsizing the drive mechanism. Further, since the magnetic fields of the bare chip and the magnet are parallel to each other, the magnetic flux density received by the magnetically sensitive portion of the bare chip cannot be increased. The sensitivity of the Hall element is proportional to the magnetic flux density received by the bare chip.
Therefore, it is desirable to place the Hall element as close to the magnet as possible so that the direction of the magnetic field is also orthogonal to the bare chip. However, as described above, it is difficult to achieve any of the conventional configurations.

Therefore, an object of the present invention is to provide a sensor device capable of increasing detection sensitivity while preventing an increase in size.

[0007]

In order to achieve the above object, the present invention provides a sensor device for detecting the position or speed of an object which generates a magnetic field or an electric field extending parallel to a mounting surface, wherein the magnetic field or the magnetic field is used. A sensor device comprising: a detection element having a detection surface for detecting an electric field; and a lead for supporting the detection element on the mounting surface with the detection surface orthogonal to the direction of the magnetic field or the electric field. I will provide a.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a mounted state of the Hall element in the present invention. FIG. 2 is a plan view showing a configuration of a main part of the Hall element according to the present invention during manufacturing, and a plan view showing a state after completion of the Hall element of the present invention.

First, the manufacturing process will be described. As shown in FIG. 2, a lead frame 8a for mounting a bare chip 2 (semiconductor chip) is punched into a U-shape, and a portion of the lead frame 8a where an inner lead is formed is formed. A cross-shaped bare chip 2 is mounted (the electrode surface is upward) using an adhesive or the like in the central portion. Inside the lead frame 8a, an L-shaped lead frame 8b (the right end of the horizontal portion in FIG. 2 is an inner lead) is arranged adjacently, and the L-shaped inner lead is provided at a symmetrical position with respect to the bare chip mounting portion. A lead frame 8c having a left end of the horizontal portion of FIG. 2 as an inner lead is arranged. Further, a lead frame 8d having an L-shaped inner lead (the left end of the horizontal portion in FIG. 2 is the inner lead) is arranged at a position symmetrical with the lead frame 8a except the bare chip mounting portion. An electrode of the bare chip 2 and each of the lead frames 8a, 8b, 8c, 8d are electrically connected by a gold wire 3.

Further, as shown in FIG. 3, a resin mold 4 for sealing is applied to a portion including the bare chip 2 and the gold wire 3. Since this resin mold 4 follows the shape of the bare chip 2, it is thin in the thickness direction. Then, the lead frames 8a, 8b, 8c, 8d
The excess portion on the outer lead side is cut by a cutting machine, and the outer lead portion left on the resin mold 4 side is bent at an angle of 90 degrees so as to be orthogonal to the plane of the bare chip 2. At this time, as shown in FIGS. 1 and 3, the lead frames 8a and 8b are bent in mutually opposite directions, and similarly, the lead frames 8c and 8d are also bent in mutually opposite directions. With such a lead structure,
When mounted on the printed circuit board 5, the bare chip 2 can be positioned vertically.

That is, the Hall element is mounted on the printed board 5 by soldering or the like in an upright state as shown in FIG. Since the mounting surface of each outer lead is orthogonal to the plane of the bare chip 2, it is arranged so that the detection surface of the bare chip 2 faces the direction of the magnetic field 7 of the magnet 6, and the Hall element is vertical. are doing. Since the thickness direction of the bare chip 2 faces the magnet 6, the distance L between the bare chip 2 and the magnet 6 is significantly smaller than in the conventional case. As a result, the change in the magnetic flux density that the bare chip 2 receives from the magnet 6 increases, and the sensitivity of the Hall element increases. Further, since the distance L between the bare chip 2 and the magnet 6 is reduced, the bare chip 2 also serves as a surface resistance for the magnet rotor.

[0012]

As described above, according to the present invention, since the plane of the semiconductor chip and the ends of the leads are arranged so as to be orthogonal to the mounting surface of the printed circuit board or the like, the magnetic sensitivity of the Hall element is increased. Can be made. Further, by arranging the semiconductor chip in the vertical position, the distance between the semiconductor chip and the magnet can be shortened, and the device can be downsized.

[Brief description of drawings]

FIG. 1 is a front view showing a mounted state of a Hall element according to the present invention.

FIG. 2 is a plan view showing the configuration of the main part of the Hall element of the present invention during manufacturing.

FIG. 3 is a plan view showing a state after completion of the Hall element of the present invention.

FIG. 4 is a plan view showing a configuration of a main part of a conventional Hall element.

FIG. 5 is a plan view showing a positional relationship between a tip portion and a magnet in a conventional Hall element.

FIG. 6 is a front view showing a mounted state of a conventional Hall element.

[Explanation of symbols]

 2 Bare chip 4 Resin mold 5 Printed circuit board 6 Magnet 7 Magnetic field 8a, 8b, 8c, 8d Lead frame 10 Hall element

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display area H01L 43/06 G01R 33/06 H

Claims (2)

[Claims] 1. A sensor device for detecting the position or speed of an object that generates a magnetic field or an electric field extending parallel to a mounting surface, comprising: a detection element having a detection surface for detecting the magnetic field or the electric field; A sensor device comprising a lead for supporting the detection element on the mounting surface at right angles to the direction of the magnetic field or the electric field. 2. The sensor device according to claim 1, wherein the detection element is a Hall element, and the lead is connected to the Hall element by a bonding wire and supports the Hall element in a state of being sealed with resin. .