JP2007037010A - High frequency circuit module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance a reflection property with simple structure by strengthening connection between an outer conductor of a connector and a GND of a dielectric substrate by connecting, with a chassis, a strip line formed on the substrate and a GND pattern for forming a GSG fixing a conductor spring thereto, in a high frequency circuit module. <P>SOLUTION: A high frequency circuit module comprises: a connector 4 with an outer conductor 4b provided on the outer surface of a conductor chassis 3; a strip line 2 installed inside the conductor chassis 3 and formed on the surface of a dielectric substrate 1; a conductor member 5 for connecting a terminating portion of the strip line 2 with the inner conductor 4a of the connector 4; lands 6 disposed on both sides of the terminating portion of the strip line 2 and electrically connected on the surface of the dielectric substrate 1 via a ground conductor 8 and a through-hole 9 within the dielectric substrate 1; and a conductive elastic member 7 connected with the inner surface of the conductor chassis 3 fixed with the lands 6. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a high-frequency circuit module, and more particularly, to a connection between a coaxial connector fixed to a casing and a microwave circuit board.

  Conventionally, in impedance matching and reflection characteristic improvement of input / output parts of high frequency circuit modules such as microwave band and millimeter wave band, there are various methods for connecting a coaxial connector fixed to a casing (conductor chassis) and a circuit board. Efforts are being made. For example, in FIG. 1 of Japanese Patent Laid-Open No. 6-112707 (see Patent Document 1), the flange 15 of the high-frequency coaxial connector 10 is in close contact with the outer surface for the purpose of reducing the cost without causing a mismatch in characteristic impedance. A plurality of L-shaped metal blocks 30 comprising a vertical plate 31 through which the central conductor portion passes through the axial hole and a horizontal plate 32 having a pair of screw holes 35 into which the machine screws 9 are screwed to the back surface side; A metal base 40 that is sufficiently larger than the circuit board 1 on which the L-shaped metal block 30 is fixedly mounted is provided by screwing the small screw 9 into the screw hole 35 in a state where the bottom surface of the horizontal plate 32 is in close contact with the upper surface. A microwave in which the rear surface of the side edge of the circuit board 1 is closely fixed to the upper surface of the horizontal plate 32 of the L-shaped metal block 30 and the center conductor 11 is closely connected to the upper surface of the stripline 2 and connected. Mounting structure of the road module is described.

  Further, FIG. 2 (see Patent Document 2) of Japanese Patent Laid-Open No. 9-237658 discloses means for reliably connecting the conductive flange constituting the ground connection portion of the high frequency connector and the ground line on the high frequency circuit board through the shortest path. The ground plate 1 is configured by forming a metal plate in a shape in which the high-frequency connector 2 and the surface of the high-frequency circuit board 6 are in contact with each other without any gap, for example, a fork and an L shape. In use, the side surface portion 11 is fastened together with the conductive screw 3 across the flange 10 and the housing 20 of the high frequency connector 2, and the bottom surface portion 12 is conductively joined to the ground line on the high frequency circuit board 6. A method for joining a high-frequency connector and a connector joining component are described.

  In FIG. 1 (see Patent Document 3) of Japanese Patent Laid-Open No. 8-203619, the coaxial connector 1 includes a flange portion 2 and a shell portion 3 as means for connecting the coaxial cable to the substrate without being lifted or displaced by the coaxial connector. A flange portion 2 is provided on the inside of the panel, and a shell portion 3 is provided on the outside of the panel so that the center contact 32 of the coaxial cable 31 extends on the first conductive pattern 6 of the substrate 5. The portion 2 is provided with a conductive attachment portion connected to the second conductive pattern 7 on the substrate 5 in the vicinity of the first conductive pattern 6, and the attachment portion is fixed to the substrate 5 and a coaxial connector A mounting structure with the substrate is described.

JP-A-6-112707 (FIG. 1)

Japanese Patent Laid-Open No. 9-237658 (FIG. 2)

JP-A-8-203619 (FIG. 1)

  However, in the one described in Patent Document 1, the outer conductor 12 of the high-frequency coaxial connector 10 fixed to the L-shaped metal block 30 is connected to the ground conductor 3 of the stripline 2 via the machine screw 8. Although the distance between the outer conductor of the high-frequency coaxial connector 10 and the circuit board 1 is shortened, the reflection characteristics are improved, but the circuit board 1 and the L-shaped metal block 30 are assembled on the metal base 40, and the assembly is complicated. At the same time, the circuit board 1 and the metal base 40 need to be aligned.

  Moreover, in the thing of patent document 2, since it has the structure where the high frequency connector 2 and the housing | casing 20 are directly fixed and the ground is connected with the ground plate 1, alignment with the housing | casing 20 and the high frequency circuit board 6 is carried out. However, there is a problem that heat stress concentrates on the solder 7 installed on the high frequency circuit board 6 side through the ground plate 1 due to the difference in thermal expansion coefficient between the housing 20 and the high frequency circuit board 6. It was.

  Moreover, in the thing of patent document 3, the board | substrate 5 is notched and the flange part 2 of the coaxial connector 1 is screwed directly to the 2nd conductive pattern 7 of the board | substrate 5, and the outer conductor of the coaxial connector 1 is connected. Although the distance between the grounds with the substrate 5 can be shortened, the structure of the substrate 5 becomes complicated and there is a problem in that it takes time and effort to work.

  The present invention has been made to solve the above-described problems, and in particular, a high-frequency module capable of improving the reflection characteristics even when the stripline ground conductor (high-frequency ground) is disposed on the inner layer of the circuit board. The purpose is to provide.

  The high-frequency circuit module according to the invention of claim 1 includes a connector in which an outer conductor is provided on an outer surface of a conductor chassis, a strip line installed inside the conductor chassis and formed on the surface of a dielectric substrate, and the strip. A conductor member connecting the end of the line and the inner conductor of the connector, and disposed on both sides of the end of the strip line, and on the surface of the dielectric substrate via a ground conductor and a through hole in the dielectric substrate; A land to be electrically connected, and a flat portion fixed to the land, and a conductive elastic member extending toward the connector and connected to the inner surface of the conductor chassis.

  According to a second aspect of the present invention, in the high-frequency circuit module, the through hole is a through-hole through hole penetrating the dielectric substrate, a hole is provided at one end of the elastic member, and a fixing member is inserted into the hole. In addition, the other end portion of the fixing member is inserted into a hole portion provided in the conductor chassis through the through-hole through hole.

  The high-frequency circuit module according to a third aspect of the present invention is the high-frequency circuit module according to the first or second aspect, wherein the elastic member is substantially U-shaped and is connected to the conductor chassis at the arc portion. is there.

  A high-frequency circuit module according to a fourth aspect of the present invention is a conductive sheet instead of the elastic member according to the first aspect, wherein one end of the conductive sheet is fixed to the land and the other end is a back surface of the dielectric substrate. 2. The conductive sheet according to claim 1, wherein the conductive sheet is fixed and is in close contact with a side surface end portion of the dielectric substrate orthogonal to the strip line and an inner surface of the conductor chassis.

  As described above, according to the first aspect of the present invention, since the RF / GND (high frequency ground) of the strip line and the conductor chassis are electrically connected using the connection spring having elasticity, the connector, the dielectric substrate, The connection portion is flexible and can be stabilized against temperature change and mechanical stress, and contributes to stabilization of input / output characteristics and reflection characteristics electrically.

  According to the invention of claim 2, since the fixing of the land and the connection spring is screwed, there is a degree of freedom in selecting the pattern material of the connection part of the strip line formed on the dielectric substrate, and the design And the convenience of work can be improved.

  According to the invention which concerns on Claim 3, since a connection spring is made into a substantially U shape and this circular arc part contacts a conductor chassis, the connection by the press of a contact part becomes reliable.

  According to the invention of claim 4, since the RF / GND of the strip line and the conductor chassis are electrically connected using the conductive sheet having elasticity, the connecting portion between the connector and the dielectric substrate is flexible, and the temperature It can be stabilized against changes and mechanical stress, and contributes to stabilization of input / output characteristics and reflection characteristics electrically. Further, since the conductive sheet is connected in the manufacturing process of the dielectric substrate, which is the pre-process, the module assembly in the post-process is simplified and the workability is good.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to FIG. FIG. 1a is a plan view of a main part of the high-frequency circuit module according to the first embodiment. In FIG. 1a, reference numeral 1 denotes an insulating material such as a glass epoxy base material, a fluororesin (polytetrafluoroethylene) base material, or ceramic. A dielectric substrate, 2 is a strip line arranged in a pattern on the dielectric substrate 1, 3 is a conductor chassis (metal housing) that houses and supports the dielectric substrate 1, and 4 is a high-frequency connector that passes a high-frequency signal of the strip line 2 (Connector) comprising a core wire (inner conductor) 4a and a connector ground (outer conductor) 4b. 5 is a conductor ribbon (conductor member) made of gold foil, copper foil, or the like that connects the strip line 2 and the core wire 4a, 6 is a land (GND pattern) disposed opposite to both sides so as to straddle the strip line 2, and 7 Is a substantially U-shaped connection spring (elastic member) made of phosphor bronze, and an enlarged view thereof is shown in FIG. 1b. In the drawings, the same reference numerals indicate the same or corresponding parts.

  2 is a cross-sectional view of the main part of the high-frequency circuit module according to the first embodiment. In FIG. 2, 8 is a ground conductor (high-frequency ground) of the strip line 2 provided on the inner layer of the dielectric substrate 1, and 9 Is a via (through-hole plating hole) that electrically connects the ground conductor 8 and the land 6. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  Next, the operation will be described. 1 and 2, first, a desired stripline 2 pattern and lands 6 on both sides of the stripline 2 near the connector 4 side are formed on the surface of the double-sided metallized substrate by photolithography. Next, a partial region of the land 6 is subjected to through-hole drilling, and then a through-hole plating hole (through-hole) 9 is formed by electroless plating and electrolytic plating. Thereby, the land 6 and the ground conductor 8 are connected in common. In order to form a multilayer substrate, a dielectric substrate 1 is configured by further laminating a base material on the ground conductor 8 side and performing lamination press.

  Next, a through hole is provided in a predetermined portion on the outer surface of the conductor chassis 3 to attach the connector 4, and the inner conductor 4 a of the connector 4 is inserted into the conductive chassis 3. Next, the termination pattern of the strip line 2 of the dielectric substrate 1 and the inner conductor 4 a are connected by thermocompression bonding or soldering with the conductor ribbon 5. Next, the land 6 and the connection spring 7 are fixed with a solder material. Therefore, when the dielectric substrate 1 is a glass epoxy base material or a fluororesin base material, the strip line 2 has a copper foil plated with nickel, and when the dielectric substrate 1 is a ceramic substrate, the strip line 2 The surface pattern is preferably made of molybdenum (Mo) or tungsten (W) plated with nickel.

  Next, the dielectric substrate 1 is finely moved so that the connection spring 7 is pressed against the conductor chassis 3, and then the dielectric substrate 1 and the conductor chassis 3 are fixed by a known means such as adhesion or screwing. Here, the connection spring 7 is connected to the conductor chassis 3 at its arc portion by the elastic force of phosphor bronze.

  From the above, the outer conductor 4b of the connector 4 and the ground conductor 8 of the dielectric substrate 1 are brought into contact (connection) between the lands (GND pattern) 6 provided on both sides in the vicinity of the strip line 2 and the conductor chassis 3 by the elasticity of the connection spring 7. Since the gap between the strip line 2 and the La GND pattern 6 arranged on both sides thereof is GSG (GND-Signal-GND) connection, the impedance matching can be improved and the reflection characteristics can be improved. Improve. Further, since the connection spring 7 is soldered to the dielectric substrate 1 and fixed to the conductor chassis 3 using the flexibility of the conductor ribbon 5, mechanical stress due to changes in the environmental temperature of the module is alleviated and the quality of the module can be ensured.

Embodiment 2. FIG.
The second embodiment of the present invention will be described below with reference to FIG. FIG. 3A is a plan view of a main part of the high-frequency circuit module according to the second embodiment. In FIG. 3A, reference numeral 71 denotes a substantially U-shaped vertical connection spring having a flat (flat) portion made of a phosphor bronze material. FIG. 3B shows an enlarged view of the second connection spring 71b which is an (elastic member) and includes a first connection spring 71a and a second connection spring 71b which are mirror-symmetrical. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  FIG. 4 is a cross-sectional view of a main part of the high-frequency circuit module according to the second embodiment. Depending on the mounting density around the connection portion between the strip line 2 and the connector 4, the inner conductor of the connector 4 can be formed by making the connection spring vertical. Even if the shape such as 4a changes, the design margin of the input / output unit at the time of module design is improved. In the figure, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

Embodiment 3 FIG.
The third embodiment of the present invention will be described below with reference to FIG. FIG. 5a is a plan view of a main part of the high-frequency circuit module according to the third embodiment. In FIG. 5a, reference numeral 72 denotes a flat spring and a substantially U-shaped connecting spring having a flat portion and a hole in the flat portion. (Elastic member), and an enlarged view thereof is shown in FIG. Reference numeral 10 denotes a screw (fixing member) to be inserted into the connection spring 72. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  FIG. 6 is a cross-sectional view of a main part of the high-frequency circuit module according to the third embodiment. Reference numeral 11 denotes a through-hole plating hole (through-hole) that penetrates from the land 6 on the surface of the dielectric substrate 1 to the back surface of the dielectric substrate 1. Through-hole) and passes through the ground conductor 8 of the dielectric substrate 1. Reference numeral 12 denotes a screw hole (hole) of the conductor chassis 3 provided below the through-hole plating hole 11. In the figure, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

  Next, the operation will be described. 5 and 6, the through-hole plating hole 11 provided in the dielectric substrate 1 is subjected to through-hole drilling after laminating and pressing the substrate, and then electrolessly and electrolytically plated to form the land 6 of the dielectric substrate 1. The ground conductor 8 is electrically connected. Thereafter, if necessary, the back surface of the dielectric substrate 1 is etched with a desired pattern. In the third embodiment, the pattern formation of the strip line 2 on the surface of the dielectric substrate 1 is performed before the substrate is laminated as in the first and second embodiments. .

  Next, a through hole is provided in a predetermined portion on the outer surface of the conductor chassis 3 to attach the connector 4, and the inner conductor 4 a of the connector 4 is inserted into the conductive chassis 3. Next, the termination pattern of the strip line 2 of the dielectric substrate 1 and the inner conductor 4 a are connected by thermocompression bonding or soldering with the conductor ribbon 5.

  Next, the screw 10 is inserted into the connection spring 72 and the through-hole plating hole 11 on the land 6, and at the same time, the dielectric substrate 1 is finely moved so as to press the connection spring 72 against the conductor chassis 3. The dielectric substrate 1 and the conductor chassis 3 are fixed with screws 10. Here, the connection spring 72 is connected to the conductor chassis 3 at the arc portion thereof by the elasticity of phosphor bronze. That is, the land 6 and the connection spring 72 are connected, and the dielectric substrate 1 and the conductor chassis 3 are fixed.

  As described above, in the first and second embodiments, the connection between the strip line 2 and the land 6 is performed by soldering. However, by attaching the fixing member 10, the connection spring 72, the land 6 and the dielectric substrate 1 are connected. Since the conductor chassis 3 is fastened together, workability can be improved. In addition, since soldering is not required, there is an advantage that design flexibility can be obtained in selecting a pattern material constituting the strip line 2 and the land 6 of the dielectric substrate 1.

Embodiment 4 FIG.
Embodiment 4 of the present invention will be described below with reference to FIG. FIG. 7 is a plan view of a main part of the high-frequency circuit module according to the fourth embodiment. In FIG. 7, reference numeral 13 denotes a GND conductor (conductive sheet) made of gold foil or copper foil. In the figure, the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

  FIG. 8 is a cross-sectional view of a main part of the high-frequency circuit module according to the fourth embodiment. The GND conductor 13 is connected in contact with the conductor chassis 3 via the side end portion orthogonal to the strip line 2 of the dielectric substrate 1. Is done. In the figure, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

  Next, the operation will be described. 7 and 8, a desired stripline 2 pattern and lands 6 are formed by photoengraving on both sides of the stripline 2 near the connector 4 side on the surface of the double-sided metallized substrate. Next, a part of the land 6 is subjected to through-hole drilling, and then a through-hole plating hole 9 is formed by electroless plating and electrolytic plating. Thereby, the land 6 and the ground conductor 8 are connected in common. In order to form a multilayer substrate, a dielectric substrate 1 is constructed by further laminating a base material on the ground conductor 8 side, performing lamination press, and etching the outer surface of the laminated press substrate with a desired pattern (referred to as S-plane land). To do.

  Next, a through hole is provided in a predetermined portion on the outer surface of the conductor chassis 3 to attach the connector 4, and the inner conductor 4 a of the connector 4 is inserted into the conductive chassis. Next, the termination pattern of the strip line 2 of the dielectric substrate 1 and the inner conductor 4 a are connected by thermocompression bonding or soldering with the conductor ribbon 5.

  Next, a GND conductor 13 (conductive sheet) such as a copper foil that passes through the land 6 of the dielectric substrate 1 and the side edge of the dielectric substrate 1 and is soldered to the opposite land (S surface land) of the dielectric substrate 1. The dielectric substrate 1 is fixed to the conductor chassis 3 so as to be pressed against the conductor chassis 3. Here, the GND conductor 13 is a sheet having a thickness of 1 mil in the case of a gold foil, and a thickness of about 35 μm in the case of a copper foil. When the dielectric substrate 1 is pressed against it, it has a function as an elastic body.

  From the above, by using a conductive sheet as an alternative to the connection spring, the GND connection between the connector 4 and the dielectric substrate 1 is possible, the reflection characteristics at the connector connection portion are stable, and the same reflection as in the first to third embodiments. Characteristics are obtained. Moreover, since the GND conductor 13 can be soldered in the manufacturing process of the dielectric substrate 1, the module assembly for fixing to the conductor chassis 3 is simplified.

  In addition, when a through-hole plating hole or the like is provided in the side surface end portion of the dielectric substrate 1 instead of the GND conductor 13, it has a connection function corresponding to the GND conductor 13 described in the fourth embodiment. poor.

  The connection springs described in the first to third embodiments have a substantially U-shape. However, an elastic body having a flat portion that can be connected to the land 6 is a coil spring or a leaf spring. May be.

  The conductive sheet described in the fourth embodiment is a gold foil or copper foil, but may be a conductive rubber sheet or a soft conductive adhesive sheet as long as it is an elastic body having a flat portion that can be connected to the land 6. .

It is a principal part top view of the high frequency circuit module by Embodiment 1 of this invention. It is principal part sectional drawing of the high frequency circuit module by Embodiment 1 of this invention. It is a principal part top view of the high frequency circuit module by Embodiment 2 of this invention. It is principal part sectional drawing of the high frequency circuit module by Embodiment 2 of this invention. It is a principal part top view of the high frequency circuit module by Embodiment 3 of this invention. It is principal part sectional drawing of the high frequency circuit module by Embodiment 3 of this invention. It is a principal part top view of the high frequency circuit module by Embodiment 4 of this invention. It is principal part sectional drawing of the high frequency circuit module by Embodiment 4 of this invention.

Explanation of symbols

1 dielectric substrate, 2 strip line, 3 conductor chassis, 4 connector, 4a core wire (inner conductor), 4b outer conductor, 5 conductor ribbon (conductor member), 6 land (GND pattern), 7 connection spring (elastic member), 8 ground conductor (high frequency ground), 9 via (through hole), 10 screw (fixing member), 11 through-hole plated hole (through hole through hole), 12 screw hole (hole), 13 GND conductor (conductive sheet) 71 connection spring (elastic member), 72 connection spring (elastic member).

Claims (4)

A connector having an outer conductor provided on the outer surface of the conductor chassis, a strip line installed inside the conductor chassis and formed on the surface of the dielectric substrate, an end portion of the strip line, and an inner conductor of the connector A conductor member to be connected, a land disposed on both sides of the end portion of the strip line, and electrically connected to the ground conductor in the dielectric substrate via a through hole on the surface of the dielectric substrate, and fixed to the land And a conductive elastic member that extends toward the connector and is connected to the inner surface of the conductor chassis. The through-hole is a through-hole through-hole penetrating the dielectric substrate, a hole is provided at one end of the elastic member, a fixing member is inserted into the hole, and the other end of the fixing member is connected to the through-hole. The high-frequency circuit module according to claim 1, wherein the high-frequency circuit module is inserted into a hole provided in the conductor chassis through a hole through hole. The high-frequency circuit module according to claim 1, wherein the elastic member has a substantially U shape, and is connected to the conductor chassis at the arc portion. A conductive sheet is used in place of the elastic member according to claim 1, one end of the conductive sheet is fixed to the land, the other end is fixed to the back surface of the dielectric substrate, and the conductive sheet is connected to the strip line. 2. The high-frequency circuit module according to claim 1, wherein the dielectric substrate is in close contact with a side end portion of the dielectric substrate orthogonal to the inner surface of the conductor chassis.

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