JP3074260B2 - Connector assembly for detachably connecting a printed wiring board to a coaxial transmission line connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to microwave and other high frequency communication systems and, more particularly, to a connector assembly for removably connecting a coaxial transmission line to a printed circuit board housed in a metal enclosure.

[0002]

BACKGROUND OF THE INVENTION Microwave and millimeter wave coaxial connectors are widely used to interconnect components of various communication systems with coaxial cables. These components are typically supported by a housing and printed wiring board housed in a metal enclosure. Connections to and from this enclosure are made by shielded coaxial connections. This results in a continuous border of metal around the entire microwave circuit. The coaxial connector is fixed to the wall of the metal enclosure. A feedthrough system communicates between the coaxial connector and a printed wiring board housed in a metal enclosure.

FIGS. 1 and 2 are simplified representations of a microwave printed wiring board of an enclosure 11 having a coaxial connector 12 according to the prior art. Connector 1
2 is an SMA type connector, but may be another type of coaxial connector, for example, an N type or BNC type connector. A printed wiring board 14 having stripline leads 17 interconnecting various components is supported within enclosure 11. Usually, the feedthrough pins 18 are soldered to the printed wiring board stripline leads 17. Soldering feedthrough pins to a printed wiring board stripline has several significant disadvantages. Solder joints are hard and brittle, and the thermal expansion and shrinkage of the aging causes the solder joint to fatigue and eventually break. In addition, to remove a connector or printed wiring board for repair or replacement,
The solder must be removed, and the process can damage the printed wiring board. Soldering and re-soldering are time consuming operations requiring skill.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a connector assembly for removably connecting a coaxial connector to a printed wiring board. It is yet another object of the present invention to provide a connector assembly that transitions from a coaxial line to a microstrip. A connector assembly that accomplishes these or other objects of the present invention includes a metal housing, a microstrip formed by leads on one side, and a ground, or ground plane, on the other side. The circuit is housed in a metal housing. The housing also includes a low impedance coaxial line section. The coaxial line section is formed by a central conductor supported by a dielectric sleeve in a through hole in one wall of the housing. A connector having leads connected to the microstrip leads and a body having a central insulating socket remote from a ground plane on the surface of the printed wiring board form a transmission line section. Said center conductor is slip fitted into said socket;
As a result, the coaxial connector can be easily attached,
Printed wiring boards can be connected to coaxial transmission lines.

[0005]

BRIEF DESCRIPTION OF THE DRAWINGS Further objects and features of the present invention will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings. Please refer to FIG. 1 and FIG. Printed circuit board circuits are supported on shelves formed at the base of enclosure 11. This printed wiring board includes a microstrip transmission line formed by a conductor 17 and a conductive ground plane 19 formed on the lower surface of the printed wiring board. Cover 21
Completes the housing of the enclosure 11. The outer section 22 of the conventional coaxial connector 12 is locked to the housing wall by screws 23. The central conductor or pin 18 of the connector is connected to the through hole 2 in the housing wall.
7 and is soldered to the microstrip lead 17. Coaxial connector impedance is about 5
0 ohms, which matches the stripline impedance.

Referring to FIG. 3 and FIG. The connector assembly of the present invention is shown, with the same reference numerals assigned to the same components. The ground plane 19 of the printed wiring board is connected to the ground plane section 28 formed on the upper surface of the board via connecting portions 44a and 44b.
The connector assembly 29 includes a socket 32 and a metal body 31 having right-angle pins 33 connected to the microstrip leads 17. Micro strip
Mode 17 is a matching section that creates a matching impedance
And in one embodiment this matching section 3
4 is an enlarged part . Insulation sleeve 3 of metal body 31
6 insulates this body from the ground plane section 28 to form a transmission line section. In this embodiment, the second connector 30, which is the same as the connector 29, is attached to the printed wiring board together with the connector 29 and brazed so that the connector 29 does not rotate during assembly. Dielectric sleeve 3 in housing hole 41
The central lead 42 of the coaxial connector is connected to the coaxial transmission line section formed by the central conductor 38 supported on the central conductor 9. The impedance is reduced by reducing the diameter of the dielectric sleeve. The lead 42 is connected to the center conductor 3
8 extend outwardly from the side holes 32 of the connector assembly 29.
Is slip-fitted.

[0007] The connector assembly of the present invention is 3.8G.
It operates over a wide frequency range up to Hz. The wide frequency range of operation of the present invention is achieved due to the small diameter of the insulating sleeve 36 and the addition of a low impedance matching section on the printed wiring board just behind the right angle header. Together, these two factors eliminate the high inductive effects associated with right angle headers. The inductance associated with this right angle header is minimized by using multiple connections to bring the ground 28 to the surface of the printed wiring board. FIG. 5 shows a block representing the impedance. Z0 is the impedance of the coaxial line,
Z1 is the low feedthrough impedance, Z2 is the impedance of the lead 42 to the housing, Z3
Is a lead 42 to the ground plane of the printed wiring board.
, Z4 is the impedance of the header,
Z5 is the impedance of the right angle header, Z6 is the impedance of the enlarged microstrip section, Z7
Is the impedance between the bent header end and the housing, and Z0 is the same impedance as the input. Therefore, the input coaxial impedance Z0 matches the microstrip impedance Z0.

Other Embodiments One skilled in the art will appreciate that the connector assembly described above removably connects a printed wiring board to various coaxial connectors, including SMA type connectors, N type connectors, BNC type connectors or spark plug type connectors. You will understand that it can be used for FIG. 6 and FIG.
Figure 4 shows an embodiment of the invention used to removably connect a printed wiring board to an SMA spark plug type threaded connector. As shown in FIGS. 6 and 7, the connector 12 is an SMA spark plug type screw connector which is connected to the printed wiring board 14 via the connector assembly of the present invention. Such spark plug types are well known and are commercially available. As described above, the ground surface 19 of the printed wiring board is
a, 44b connected to the ground plane section 28 on the top surface of the board. The metal body 31 included in the connector assembly 29 has a socket 32 and right-angle pins 33 connected to the microstrip leads 17 of the printed wiring board 14. However, in this embodiment, unlike the embodiment shown in FIGS. 3 and 4, the microstrip 17 has a first impedance having a low impedance shunt stub.
It has a matching section 34 consisting of two parts, a part 34a and a second part 34b having a high impedance line. These two elements match the impedance between the impedance of the spark plug type connector assembly and the impedance of the microstrip lead. The insulating sleeve 36 of the body 31 insulates the metal body 31 from the ground plane section 28 to form a transmission line section. Second connector assembly 30
(Same as connector assembly 29) is soldered to connector assembly 29 and attached to a printed wiring board to prevent rotation of connector assembly 29 during assembly.
The center lead of the SMA coaxial connector is a dielectric sleeve 39
Is a 50 ohm transmission line section formed by a center conductor 38 supported on the transmission line. Leads 42 extend outwardly from center conductor 38 and slide fit into side holes 32 of connector assembly 29.

The connector assembly shown in FIGS. 6 and 7 operates over a wide frequency range up to 3.5 GHz. Operation in this wide frequency range is made possible by the two elements 34a, 34b of the impedance matching section 34 located on the printed wiring board just behind the right angle header. The combination of these two elements eliminates the highly inductive effects associated with right angle headers. The inductance associated with the right angle header is minimized by bringing the ground ground 28 to the surface of the printed wiring board by a plurality of connections. FIG.
Indicates the impedance of the components shown in FIGS. Z0 is the impedance of the SMA coaxial connector, Z1
Is the impedance of the lead 42 with respect to the housing, Z
2 is the lead 4 for the ground plane of the printed wiring board
2, Z3 is the impedance of the header, Z4 is the impedance of the right angle header, Z5 is the impedance of the thinned microstrip matching section, Z6 is the impedance of the expanded microstrip matching section, and Z7 is the bent header end and housing. , Z0 is the same impedance as the input. Therefore, the input coaxial impedance Z0 matches the impedance of the SMA coaxial connector Z0.

[0010] An interconnect assembly is provided that allows a printed circuit board circuit in a metal housing to be replaced in the field. The embodiments described herein can be modified in various ways, and therefore the embodiments described here are not intended to be limiting, but merely disclosed for the purpose of understanding the present invention.

[Brief description of the drawings]

FIG. 1 is a plan view of a coaxial connector brazed to a printed wiring board microstrip according to the related art.

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG.

FIG. 3 is a plan view of a preferred embodiment of the coaxial-printed wiring board transition of the present invention.

FIG. 4 is a sectional view taken along lines 4-4 in FIG. 3;

FIG. 5 is an equivalent electric circuit showing impedance characteristics of a portion of the connector assembly of the present invention shown in FIGS.

FIG. 6 is a plan view of another embodiment of the present invention for detachably connecting an SMA spark plug type connector to a printed wiring board.

FIG. 7 is a sectional view taken along lines 7-7 of FIG. 6;

8 is an equivalent electric circuit showing impedance characteristics in the connector assembly of the present invention shown in FIGS. 6 and 7. FIG.

[Explanation of symbols]

12 Connector 14 Printed Wiring Board 17 Transmission Line Lead or Microstrip Lead 19 Ground Plane 28 Ground Plane Section 29 Connector Assembly 30 Connector Assembly 32 Socket 34 Impedance Matching Section 36 Insulation Sleeve 38 Center Conductor 39 Dielectric Sleeve 42 Coaxial Center Lead

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor John Stanislaus Tobias 94089, California, United States Sunnyvale Morse Avenue 1063-7-205 (56) References JP-A-5-109452 (JP, A) JP-A-4- 133276 (JP, A) JP-A-5-326079 (JP, A) JP-A-64-33867 (JP, A) JP-A-6-60943 (JP, A) JP-A-60-97577 (JP, A) JP-A-1-281688 (JP, A) JP-A 2-119362 (JP, U) JP-A-61-158081 (JP, U) JP-A 1-124686 (JP, U) (58) Fields surveyed ( Int.Cl. ⁷ , DB name) H01R 9/05 H01R 9/09 H01R 13/646

Claims (3)

(57) [Claims] 1. A connector assembly for detachably connecting a printed wiring board to a coaxial connector having a coaxial center lead, wherein the coaxial center lead is connected to a center conductor supported by a dielectric sleeve. A section, a first socket slidably receiving the center conductor, a right-angle pin connected to the socket, and a transmission line on the surface of the printed wiring board and connected to the right-angle pin. A lead, a ground plane section on the printed wiring board, and an insulating sleeve surrounding the first socket such that the first socket forms a transmission line with the ground plane section. Impedance matching between the transmission line lead and the coaxial connector A connector assembly, wherein the transmission line lead has a section. 2. A connector assembly for detachably connecting a printed wiring board to a coaxial connector having a coaxial center lead, wherein the coaxial center lead is connected to a center conductor supported by a dielectric sleeve. A section, a first socket slidably receiving the center conductor, a right-angle pin connected to the socket, and a transmission line on the surface of the printed wiring board and connected to the right-angle pin. A lead, a ground plane section on the printed wiring board, and an insulating sleeve surrounding the first socket such that the first socket forms a transmission line with the ground plane section. Impedance matching between the transmission line lead and the coaxial connector The transmission line lead has a section , and the impedance matching section is
At least one enlargement near said right angle pin
A connector assembly comprising a portion . 3. The first socket, the right angle pin, the transmission line lead, the ground plane section, the insulation sleeve, and the transmission line socket.
3. The connector assembly of claim 2, wherein the impedance matching section of the cable is configured to match the impedance of the coaxial connector and the transmission line lead.