JPH0651823U - Holder for holding magnetic sensor - Google Patents

Abstract

(57) [Abstract] [Purpose] The sensor chip of the magnetic sensor is connected to the lead frame of the holder on the surface opposite to the magnetic sensitive surface and the magnetic sensor holding Get the holder. [Structure] A notch 7 is formed in a holder 5 so that the vicinity of a joint where a terminal of a sensor chip and a connecting portion of a lead frame are connected to each other penetrates. Half of the lead frames 6a to 6b integrally formed with the holder 5 are embedded in the sensor mounting portion vertical to the mounting surface of the holder, and the end portion on the connection portion side is taken out in parallel with the holder mounting surface. You may make it take out vertically from the part parallel to a holder attachment surface. Lead frame 6a
The sensor chips soldered to 6d may be bonded to the holder 5 and the lead frames 6a to 6d from the back. The lead frames 6a to 6d may be pulled out to the rear of the holder 5 at a position higher than the mounting surface of the holder 5.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a magnetic sensor, and more particularly to a holder that holds a sensor chip.

[0002]

[Prior art]

 For example, there is known a magnetic sensor that detects the rotational position and the rotational speed of a rotating body by disposing it near a capstan motor such as a video tape recorder (VTR) and an audio tape recorder, and other various motors. FIG. 15 shows an example of a conventional magnetic sensor, which is composed of a sensor chip 34 and a holder 35. The holder 35 has fixing portions 35a and 35b for fixing to a circuit board or the like at the bottoms of the left and right ends, and the portion sandwiched between the fixing portions 35a and 35b is higher than the bottom surface of the fixing portions 35a and 35b. An attachment surface 38 to which the sensor chip 34 is attached is formed on the front surface of the holder 35, and four lead frames 36a, 36b, 36c, 36d are formed below the attachment surface 38 by penetrating the holder 35 in the front-rear direction. Are attached together. The front ends of the lead frames 36a to 36d slightly project forward of the holder 35 and are bent upward, and the other parts penetrate the lower part of the holder 35 and project rearward, and are bent downward.

Next, an example of attaching the sensor chip 34 to the holder 35 having the above configuration will be described. The surface of the sensor chip 34 opposite to the magnetically sensitive surface 31 contacts the mounting surface 38 formed on the holder 35, and the lower end of the sensor chip 34 is bent above the front end of the lead frame 36. It is caught in the open part. Since four terminals 37a to 37d corresponding to the lead frames 36a to 36d are formed at the lower end portion of the sensor chip 34, the respective terminals 37a to 37d and the respective lead frames 36a to 36d overlap each other, and their overlapping portions The terminals 37a to 37d and the lead frames 36a to 36d can be connected to each other by soldering. After the sensor chip 34 is attached to the holder 35, a resin or the like is applied to the connecting portions of the lead frames 36a to 36d and the terminals 37a to 37d and sealed. An example of such a magnetic sensor is described in Japanese Utility Model Laid-Open No. 62-20313.

[0004]

[Problems to be solved by the device]

 According to the conventional holder for holding the magnetic sensor as described above, the magnetic sensor 31 is connected to the end of the lead frame 36 on the magnetic sensitive surface 31 side, so that a protrusion is generated on the entire surface of the magnetic sensor. As a result, this protruding portion obstructs the magnetic sensitive surface 31 of the magnetic sensor and cannot be brought close to the motor and other rotating bodies. To solve such a problem, as described in Japanese Patent Laid-Open No. 63-34986, the connecting portion between the lead frame and the terminal of the sensor chip may be formed on the back surface side of the sensor chip.

To connect to the lead frame on the back side of the sensor chip, as described in JP-A-1-262488, the sensor chips wired on both sides are connected to the lead frame and then integrated. The magnetic sensor may be formed by molding. However, when the magnetic sensor is formed by such a method, there is a drawback that it is difficult to assemble the magnetic sensitive surface of the sensor chip with high accuracy.

In order to solve the above-mentioned problems, the present invention connects the sensor chip of the magnetic sensor to the lead frame of the holder on the surface opposite to the magnetic sensitive surface, and attaches the magnetic sensitive surface. The purpose is to provide a holder for holding a magnetic sensor with improved accuracy.

[0007]

[Means for Solving the Problems]

 According to another aspect of the invention, there is provided a magnetic sensor chip having a terminal formed on a back surface opposite to a magnetically sensitive surface, and a lead frame having a connecting portion electrically connected to the terminal of the magnetic sensor chip. A holder for holding the sensor chip together with the lead frame being integrally attached, and a notch formed in the holder so that a vicinity of a joint connecting the terminal and the connecting portion is penetrated. Was formed.

According to a second aspect of the present invention, in the first aspect of the present invention, half of the plurality of lead frames integrally formed with the holder are embedded in a sensor mounting portion perpendicular to the mounting surface of the holder. The end of the connecting part was taken out parallel to the holder mounting surface, and the other half was taken out vertically from the part parallel to the holder mounting surface.

According to a third aspect of the present invention, in the first aspect of the invention, the sensor chip soldered to the lead frame is bonded to the holder and the lead frame from the back side.

According to a fourth aspect of the invention, in the first aspect of the invention, the lead frame is pulled out to the rear of the holder at a position higher than the mounting surface of the holder on the circuit board.

[0011]

[Action]

 Align the terminals of the sensor chip with the connection parts of the lead frame attached to the holder, and press the soldering iron against the connection parts from the notches near the connection parts of these terminals to the connection parts. Can be electrically connected to the connection part. By mounting the sensor chip in the notch of the lead frame, the sensor chip mounting accuracy is improved.

[0012]

【Example】

 Hereinafter, an embodiment of a holder for holding a magnetic sensor according to the present invention will be described with reference to the drawings. In FIG. 1, the holder 5 has fixing portions 5a and 5b for the circuit board and the like on both left and right sides. The bottom surfaces of the fixing portions 5a and 5b are mounting surfaces 5f and 5f for the circuit board and the like, and the sensor mounting portions 5c and 5c perpendicular to the mounting surfaces 5f and 5f extend from the fixing portions 5a and 5b. . A rectangular cutout 7 is formed between the sensor mounting portions 5c and 5c from the upper side to the substantially central portion in the upward direction, whereby the holder 5 has a concave front shape. The notch 7 is formed so as to penetrate from the front side where the sensor chip (not shown) is attached to the rear side. In the sensor mounting portions 5c, 5c, a step portion is formed on the cutout 7 side substantially at the center in the thickness direction, and the lateral width dimension from the front side of the cutout 7 to the step portion is equal to that of the cutout 7. It is larger than the width from the rear side to the step. The stepped portion serves as a chip receiving portion 5d to which a sensor chip described later is attached.

To the holder 5, four lead frames 6a, 6b, 6c, 6d for connecting with a plurality of terminals formed on a sensor chip (not shown) are attached by integral molding. One end of each of the lead frames 6a to 6d is inserted from a lower surface side into a bridge 5g connecting the fixing portions 5a and 5b of the holder 5 and extends upward. Of the four lead frames 6a to 6d, the ends of the lead frames 6a and 6d at both ends are embedded in the sensor mounting portions 5c and 5c along the sensor mounting portions 5c and 5c, and the sensor mounting portion 5c. The upper part of 5c is bent in a direction parallel to the mounting surfaces 5f, 5f of the holder 5, and the ends are opposed to each other, and protrudes from the inner wall of the notch 7. The lead frames 6b and 6c in the center penetrate the bridge 5g in a direction perpendicular to the mounting surfaces 5f and 5f of the holder 5 as they are, and project from the bottom surface of the notch 7, and the ends thereof are the lead frames 6a, It is located below the end of 6d.

The holder 5 having the above-described structure is made by stacking two molds and integrally molding resin. The boundary between the two molds remains as a partition line as indicated by reference numeral 12 in FIG. The aforementioned chip receiving portion 5d is formed closer to the sensor chip side than the partition line 12 by 0.1 to 0.2 mm. Further, the surfaces of the lead frames 6a to 6d on the sensor chip side are arranged so as to coincide with the partition lines 12.

Next, a procedure for fixing the sensor chip 4 to the holder 5 will be described. In FIG. 2, the sensor chip 4 is brought into contact with the chip receiving portion 5d inside the notch 7. Terminals are formed on the surface of the sensor chip 4 opposite to the magnetically sensitive surface 1 at positions corresponding to the connecting portions 6a, 6b, 6c, 6d of the lead frame 6, and each terminal has a solid shape. Solder 9 is put. The height L of the solder 9 is set in the range of 0.1 to 0.2 mm in consideration of the distance between the lead frames 6a to 6d and the sensor chip 4 when the sensor chip 4 is attached. . When the sensor chip 4 is positioned with respect to the holder 5, the solder 9 is interposed between the terminals of the sensor chip 4 and the lead frames 6a, 6b, 6c, 6d.

Next, as shown in FIG. 3, a soldering iron 8 is inserted into the notch 7 from the back surface side of the sensor chip 4, and the soldering iron 8 is brought into contact with the lead frames 6a to 6d to fix it. Melt the shaped solder 9. Since the solder 9 contracts when it solidifies, the sensor chip 4 is pulled toward the chip receiving portion 5d, and the assembling accuracy can be improved. The cross-sectional shape of the tip of the soldering iron 8 is almost the same as the shape of the notch 7, and by pressing the soldering iron 8 once, the lead frames 6a to 6d and the corresponding sensor chip 4 can be pressed. Each terminal can be soldered.

FIG. 4 shows a state in which the sensor chip 4 is attached to the holder 5 as described above from the back surface side. As shown in FIG. 4, almost the entire portion of the holder 5 to which the sensor chip 4 is fixed by soldering, where the lead frames 6a to 6d and the sensor chip 4 are connected by soldering, that is, the magnetically sensitive surface of the sensor chip 4 As shown in FIG. 5, the adhesive 9 is applied to the entire surface on the opposite side to the magnetic sensor to complete the magnetic sensor. By applying the adhesive 9 over almost the entire surface of the sensor chip 4 connected to the lead frames 6a to 6d, the fixed strength of the sensor chip 4 with respect to the holder 3 can be further improved, and the leads 3 It is possible to protect the connection parts of the frames 6a to 6d and the terminals. Normally, when an adhesive is used, the problem is that the adhesive flows out and affects other members, but in this embodiment, the wall inside the cutout 7 serves as a flow stop for the adhesive 9. In addition, since the adhesive 9 is prevented from flowing out of the holder 3, the adhesive 9 has no influence on other members.

As described above, the terminals are formed on the surface of the sensor chip 4 opposite to the magnetically sensitive surface 1, and the notch of the holder 5 is formed so that the vicinity of the joint to which the lead frames 6a to 6d are connected penetrates. By forming 7 into a concave shape, the soldering connection of the sensor chip 4 to the holder 5 can be facilitated and the workability can be improved, and each terminal of the sensor chip 4 can be passed through the notch 7. It is possible to observe the connection portions of the lead frames 6a to 6d with each other, and it is possible to easily confirm the quality of the connectivity of these connection portions. Further, when connecting the terminals of the sensor chip 4 to the lead frames 6a to 6d, the lead frames 6a to 6d are arranged at positions displaced from the chip receiving surface 5d. Even if is attached, the lead frames 6a to 6d are not bent by being pressed by the solder. After the sensor chip 4 and the lead frames 6a to 6d are soldered, the sensor chip 4 is attracted to the chip receiving portion 5d due to the solidification and contraction of the solder, so that the assembling accuracy of the sensor chip 4 to the holder 5 should be improved. You can Further, of the four lead frames 5a to 5d integrally formed with the holder 5, the lead frames 6a and 6d at both ends are embedded in this portion by utilizing the sensor mounting portions 5c and 5c of the holder 5, and the tip ends thereof. The parts are bent in directions facing each other so as to be parallel to the mounting surfaces 5f and 5f of the holder 5, and taken out into the notches 7 of the holder 5, and the central lead frames 6b and 6c are mounted on the mounting surfaces 5f and 5f of the holder 5. Since the bridge 5g parallel to the above is extended as it is so as to be perpendicular to the mounting surfaces 5f, 5f of the holder 5, the width of the holder 5 can be reduced and the sensor chip can be made small. It is possible to downsize the physique of the holder 5 in order to deal with making into a mold.

The structure of the connecting portion of the lead frame is not limited to the above. Various patterns can be considered according to the size of the sensor chip 4 to be attached and the arrangement of terminals. For example, when four terminals of the sensor chip are lined up in the lateral direction, the four lead frames 10a, 10b, 10c, 10d formed integrally with the holder 5 are arranged as shown in FIG. All of the holders 5 may be arranged side by side in the lateral direction on the portion of the bridge 5g parallel to the mounting surfaces 5f, 5f on the circuit board so as to be perpendicular to the mounting surfaces 5f, 5f. If the sensor chip terminals are formed at the vertices of a quadrangle, as shown in FIG. 7, of the four lead frames 11a, 11b, 11c, and 11d, two lead frames 11a, 11b are used. Is embedded in one sensor mounting portion 5c of the holder 5, the other two lead frames 11c and 11d are embedded in the other sensor mounting portion 5c, and the leading end portions of the lead frames 11a and 11d at both ends are opposed to each other. Bend it so that it is parallel to the holder mounting surface so that it projects from the inside of the notch 7, and the center lead frames 11b and 11c face each other at a position lower than the bending position of the lead frames 11a and 11d. It may be bent so as to be parallel to the mounting surface and projected from the inner wall of the notch 7.

Further, in the above embodiment, as shown in FIG. 2, the chip receiving portion 5d is formed closer to the sensor chip 4 side than the partition line 12 in which the lead frames 6a to 6d are arranged. However, as shown in FIG. 8, the chip receiving portion 5d is formed on the partition line 12 of the holder 5, the lead frame 13 is arranged on the chip receiving portion 5d, and the tip end portion of the lead frame 13 is attached to the chip receiving portion 5d. It may be bent inside the portion 5d, and further may be bent so that the ends thereof face each other at a position of about 0.1 to 0.2 mm from the bent portion. According to this example, since the lead frame 13 connected to the sensor chip 4 is displaced rearward from the chip receiving portion 5d, even if the sensor chip on which the solid solder is mounted is attached, The solder is settled in a portion displaced by about 0.2 mm, and the lead frame 13 is not deformed by the solder.

Next, the embodiment shown in FIGS. 9 to 11 will be described. 9 to 11, the holder 14 integrally formed with the four lead frames 16a, 16b, 16c, and 16d has a rectangular cutout 22 as in the above embodiment, and has a concave shape. Has become. Lower portions on both left and right sides of the holder 14 are fixing portions 14a and 14b to a circuit board or the like, and lower surfaces of the fixing portions 14a and 14b are mounting surfaces 14f and 14f. The fixed portions 14a and 14b are connected by a bridge 14g, and a gap 20 is formed between the bridge 14g and the extended surface of the mounting surfaces 14f and 14f. From the gap 20, the base end portions of the lead frames 16a to 16d bent into appropriate shapes are drawn out to the outside. Of the four lead frames 16a, 16b, 16c, 16d, the tip ends of the lead frames 16a, 16d at both ends are bent to be parallel to the holder mounting surfaces 14f, 14f, and protrude from the inner wall portion of the notch 22. , Facing each other. The leading ends of the other lead frames 16b and 16c project upward from the bridge 14g of the holder 14 and are bent in parallel to the holder mounting surfaces 14f and 14f and in opposite directions.

As shown in FIG. 10, the lead frames 16 a to 16 d drawn out from the gap 20 to the outside are rounded upward in a hairpin shape at the rear of the holder 14 and then attached to the holder 14. At a lower position, the holder 14 is bent so as to be parallel to the mounting surfaces 14f and 14f of the holder 14 and is drawn out of the holder 14. Further, as shown in FIG. 11, the portions of the lead frames 16a to 16d that are drawn out of the holder 14 are bent so as to spread outward when viewed from above. In this way, the lead frame 16 is rolled out so as to form a hairpin shape at a position higher than the mounting surfaces 14f, 14f of the holder 14, and is pulled out at a position lower than the mounting surfaces 14f, 14f. It is possible to stabilize the mounting on the board.

Next, still another embodiment shown in FIGS. 12 and 13 will be described. In FIG. 12 and FIG. 13, the holder 17 has a notch 21 formed in the central portion to have a concave shape. Fixed parts 17a and 17b are provided on both sides of the holder 17, and the fixed parts 17a and 17b are connected by a bridge 17g. The lower end surfaces of the fixing portions 17a and 17b are mounting surfaces 17f and 17f to a circuit board or the like. Four lead frames 18a, 18b, 18c and 18d extend upward from the bridge 17g. The lead frames 18a and 18d at both ends extend along the sensor mounting portions 17c and 17c following the fixing portions 17a and 17b, and the tips of the lead frames 18a and 18d face each other from the upper portions on both sides of the inner wall of the notch 21, and the mounting surface 17f of the holder 17 is It projects in a direction parallel to 17f. On the other hand, the center lead frames 18b and 18c project upward from the bottom of the notch 21 and extend upward so as to be perpendicular to the holder mounting surface, and the tips are located below the lead frames 18a and 18d. . As shown in FIG. 13, groove portions 21 a, 21 b, 21 c, and 21 d are formed on the back surface side of the holder 17 around the roots of the lead frames 18 a to 18 d protruding from the notch 21. By forming the grooves 21a to 21d around the lead frames 18a to 18d in this manner, the fulcrum when the lead frame 18a is bent by being pressed by the sensor chip as shown in FIG. 14 is the lead frame 18a. Since the sensor chip comes into contact with the sensor chip and becomes farther than the point where the force is applied, the bending angle can be reduced and the deformation of the lead frame 18a can be minimized.

On the other hand, seven protrusions 19 a to 19 d are formed inside the notch 21 formed in the holder 17. Of these, the protrusions 19a, 19c, 19e, and 19g are formed at the vertices of the rectangular cutout 21, and the protrusions 19b, 19d, and 19f are formed at the portions between the vertices. These protruding portions 19a to 19b serve as a chip receiving portion when the sensor chip is attached to the holder. In this way, the shape of the chip receiving portion may be a protruding portion.

[0025]

[Effect of device]

 According to the first aspect of the present invention, the holder is cut out so that the vicinity of the joint where the terminal of the sensor chip and the connecting portion of the lead frame are connected penetrates. Since it can be connected to the lead frame, the process of connecting the sensor chip is facilitated and workability can be improved.

According to the second aspect of the invention, half of the plurality of lead frames integrally formed with the holder are embedded in the sensor mounting portion perpendicular to the mounting surface of the holder, and the end portion on the side of the connecting portion. Since the holder is parallel to the holder mounting surface and the other half is taken out vertically from the part parallel to the holder mounting surface, the width of the holder can be reduced and the size of the sensor chip mounted on the holder can be reduced. You can

According to the third aspect of the present invention, since the sensor chip soldered to the lead frame is adhered to the holder and the lead frame from the back side, the effect of adhering the sensor chip to the lead frame is improved and the sensor chip The electrode formed on the back side of the magnetically sensitive surface can be protected.

According to the invention of claim 4, since the lead frame is pulled out to the rear of the holder at a position higher than the mounting surface of the holder, the mounting of the holder can be made more stable.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a holder for holding a magnetic sensor according to the present invention.

FIG. 2 is a plan sectional view showing an example of a process of attaching the sensor chip to the holder.

FIG. 3 is a plan sectional view showing an example of another step of attaching the sensor chip to the holder.

FIG. 4 is a perspective view showing an example of still another step of attaching the sensor chip to the holder.

FIG. 5 is a perspective view showing an example of still another step of attaching the sensor chip to the holder.

FIG. 6 is a front view showing another embodiment of a holder for holding a magnetic sensor according to the present invention.

FIG. 7 is a front view showing still another embodiment of a holder for holding a magnetic sensor according to the present invention.

FIG. 8 is a plan sectional view showing still another embodiment of a holder for holding a magnetic sensor according to the present invention.

FIG. 9 is a front view showing yet another embodiment of a holder for holding a magnetic sensor according to the present invention.

FIG. 10 is a side sectional view of the same.

FIG. 11 is a plan view of the same.

FIG. 12 is a front view showing yet another embodiment of a holder for holding a magnetic sensor according to the present invention.

FIG. 13 is a rear view showing an enlarged main part of the embodiment.

FIG. 14 is a plan cross-sectional view showing an enlarged leading end portion of the lead frame of the embodiment.

FIG. 15 is an exploded perspective view showing an example of a conventional holder for holding a magnetic sensor.

[Explanation of symbols]

 1 magnetic sensitive surface 4 sensor chip 5 holder 6 lead frame 7 notch 5f holder mounting surface 5c sensor mounting surface 5g part parallel to holder mounting surface

Claims (4)

[Scope of utility model registration request] 1. A magnetic sensor chip having a terminal formed on a back surface opposite to a magnetically sensitive surface, a lead frame having a connecting portion electrically connected to a terminal of the magnetic sensor chip, and the lead. A magnetic sensor having a frame integrally mounted and a holder for holding the sensor chip, which is cut into the holder so that the vicinity of a joint where the terminal and the connection are connected is penetrated. A holder for holding a magnetic sensor, characterized in that a notch is formed. 2. A half of a plurality of lead frames integrally formed with the holder is embedded in a sensor mounting portion perpendicular to a mounting surface of the holder, and an end portion on a connecting portion side is taken out in parallel with the mounting surface of the holder. The holder for holding a magnetic sensor according to claim 1, wherein the remaining half is taken out in a vertical direction from a portion parallel to the holder mounting surface. 3. The holder for holding a magnetic sensor according to claim 1, wherein the sensor chip soldered to the lead frame is adhered from the back to the holder and the lead frame. 4. The holder for holding a magnetic sensor according to claim 1, wherein the lead frame is pulled out to the rear of the holder at a position higher than a mounting surface of the holder.