CN217385580U

CN217385580U - QFN packaging radio frequency chip test fixture

Info

Publication number: CN217385580U
Application number: CN202220459178.2U
Authority: CN
Inventors: 杨雪; 廖强; 张强
Original assignee: Chengdu Guoqiang Yuxing Electronic Technology Co ltd
Current assignee: Chengdu Guoqiang Yuxing Electronic Technology Co ltd
Priority date: 2022-03-04
Filing date: 2022-03-04
Publication date: 2022-09-06
Anticipated expiration: 2032-03-04

Abstract

The utility model relates to a QFN encapsulation radio frequency chip test fixture, including mounting bracket and bottom plate, mounting bracket demountable installation is on the bottom plate, surface mounting has first PCB board on the mounting bracket, mounting bracket internally mounted has the second PCB board, the one side that first PCB board deviates from each other with the second PCB board all is provided with the microstrip line, install the double-end probe in the mounting bracket, the mounting bracket is run through at the double-end probe both ends, and be connected with the microstrip line electricity on first PCB board and the second PCB board respectively, the double-end probe forms 50 ohm coaxial transmission conductors with the microstrip line, the mounting bracket lateral part still is provided with a plurality of connectors, the connector is connected with the terminal electricity of microstrip line, mounting bracket upper surface middle part still is provided with earth probe and spacing frame, earth probe installs in spacing frame. The utility model connects the microstrip line through the double-end probe, matches the radio frequency test link to the standard 50 ohm, obtains the excellent radio frequency index; the double-ended probe and the chip to be tested can not be in direct contact with each other for testing, the probe is protected, and the elasticity of the probe is prevented from being reduced.

Description

QFN packaging radio frequency chip test fixture

Technical Field

The utility model relates to a chip test frock technical field especially relates to QFN encapsulation radio frequency chip test fixture.

Background

QFN is a leadless package, square or rectangular, with a large area of exposed pads at the center of the bottom of the package for heat conduction, and conductive pads surrounding the large pads around the periphery of the package for electrical connection. It is noted that QFN packages are completely different from LCC packages, which still have epitaxial leads, but bend the leads to the bottom, while QFN packages do not have any epitaxial leads at all. Electrode contacts are arranged on four sides of the package, and due to the fact that pins are not arranged, the mounting occupied area is smaller than that of the QFP, and the height of the package is lower than that of the QFP. However, when stress is generated between the printed substrate and the package, the stress cannot be relieved at the electrode contact. The existing QFN test fixture only meets the requirements of a QFN packaging chip with a conventional lower frequency band (the radio frequency is less than or equal to 25 GHz), and the design of a test base platform needs to be changed for a high frequency band to 40G. In addition, during testing, because the detection probe contains a miniature compression spring, metal fatigue is easy to occur in repeated switching use at high and low temperatures, so that the elasticity of the spring is reduced, and the transmission effect of radio frequency signals is deteriorated.

SUMMERY OF THE UTILITY MODEL

Therefore, the QFN packaging radio frequency chip test fixture is needed to be provided for the situation that the elasticity is reduced due to the fact that the existing test tool probe is easy to use and fatigue.

QFN encapsulation radio frequency chip test fixture, including mounting bracket and bottom plate, mounting bracket demountable installation is in on the bottom plate, surface mounting has first PCB board on the mounting bracket, mounting bracket internally mounted has the second PCB board, first PCB board with the one side that the second PCB board deviates from each other all is provided with the microstrip line, install the double-end probe in the mounting bracket, the double-end probe both ends are run through the mounting bracket, and respectively with microstrip line electricity on first PCB board and the second PCB board is connected, the double-end probe with the microstrip line forms 50 ohm coaxial transmission conductors, the mounting bracket lateral part still is provided with a plurality of connectors, the connector with the terminal electricity of microstrip line is connected, mounting bracket upper surface middle part still is provided with earth probe and spacing frame, earth probe installs in the spacing frame.

Preferably, the self-locking pressing assembly comprises a back plate, a crank assembly and a pressing rod, the back plate is perpendicularly installed on the bottom plate, a crank fixing block is arranged at one end, deviating from the bottom plate, of the back plate, the upper end of the crank assembly is movably connected with the crank fixing block, the lower end of the crank assembly is movably connected with the side portion of the back plate, the pressing rod is installed at the lower end of the crank assembly, the crank assembly drives the pressing rod to move up and down, and the pressing rod is located right above the grounding probe.

Preferably, the crank assembly comprises a crank arm, a crank block and an installation part, the crank block is movably connected with the crank fixing block, one end of the crank arm is movably connected with the crank block, the other end of the crank arm is movably connected with the installation part, the side part of the installation part is movably connected with the back plate, and the pressing rod is installed at the lower end of the installation part.

Preferably, the lower end of the pressing rod is provided with a rubber head.

Preferably, the back plate is provided with a guide rail along the vertical direction, and the side part of the mounting piece is provided with a sliding block which is movably connected with the guide rail.

Preferably, the connector is an SMA radio frequency connector and a J30J connector.

The utility model discloses an useful part lies in: 1. the first PCB and the second PCB are respectively arranged on two sides of the mounting rack and connected through a double-head probe, the area of the mounting rack is reduced, and the radio frequency test link is matched with a standard 50 ohm so as to obtain an excellent radio frequency index; 2. the double-end probe can not the direct contact test with the chip that awaits measuring, and is connected through the microstrip line electricity on the first PCB board, avoids chip limit portion pin hard pressing contact probe, and the protection probe prevents that probe elasticity from descending.

Drawings

FIG. 1 is a perspective view of an embodiment of a QFN package RF chip test fixture;

FIG. 2 is an exploded view of a QFN package RF chip test fixture;

fig. 3 is a perspective view of another embodiment of a QFN packaged radio frequency chip testing jig.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1-2, the QFN packaged radio frequency chip testing fixture comprises a mounting rack 1 and a bottom plate 2, wherein the mounting rack 1 is detachably mounted on the bottom plate 2, a first PCB 3 is surface mounted on the mounting rack 1, a second PCB 4 is mounted inside the mounting rack 1, microstrip lines 31 are respectively disposed on the surfaces of the first PCB 3 and the second PCB 4 which are away from each other, a double-headed probe 11 is mounted in the mounting rack 1, two ends of the double-headed probe 11 penetrate through the mounting rack 1 and are respectively electrically connected with the microstrip lines 31 on the first PCB 3 and the second PCB 4, the double-headed probe 11 and the microstrip lines 31 form a 50 ohm coaxial transmission conductor, a plurality of connectors 12 are further disposed on the side of the mounting rack 1, the connectors 12 are electrically connected with the ends of the microstrip lines 31, a grounding probe 13 and a limit frame 14 are further disposed in the middle of the upper surface of the mounting rack 1, the grounding probe 13 is mounted in the limit frame 14. Specifically, in the present embodiment, in use, the chip 100 to be tested is placed on the mounting frame 1, specifically, within the range of the limiting frame 14, so as to prevent the chip 100 to be tested from shifting during the pressure test. Spacing frame 14 is PC plastic material, avoids using the metal, prevents electromagnetic interference, and spacing frame 14 passes through the bolt and can dismantle with mounting bracket 1 and be connected. Furthermore, a grounding probe 13 is arranged in a range encircled by the limit frame 14, and a bonding pad exposed on the lower surface of the chip 100 to be tested is abutted against the grounding probe 13 and is grounded. Be provided with a plurality of pins at the limit portion of chip 100 lower surface that awaits measuring, in order to make pin and the microstrip line 31 butt contact on the first PCB board 3 good, need exert external force when awaiting measuring on chip 100, specifically can push down the subassembly through the auto-lock, perhaps articulated upset lid, mode such as part time pressure such as cylinder, perhaps direct artifical hand press to ensure that chip 100 that awaits measuring contacts well with microstrip line 31. After chip 100 atress that awaits measuring, first PCB board 3 will do all can in step the power on double-end probe 11, make double-end probe 11 atress push down, with install the microstrip line 31 contact on the second PCB board 4 of mounting bracket 1 lower surface, form 50 omega's coaxial transmission conductor, so as to obtain more excellent radio frequency index, and after the external force of exerting on the chip 100 that awaits measuring gets rid of, because first PCB board 1 is connected with mounting bracket 1 through the spring, under the effect of spring and the 11 inside spring forces of double-end probe, first PCB board 1 resets, wait for the test next time. This kind of design can avoid double-end probe 11 direct with the pin contact of chip 100 that awaits measuring, protects double-end probe 11, prevents that the time from having been of a specified duration, and double-end probe 11 elasticity descends, and the test is inaccurate, has improved double-end probe 11's life.

As shown in fig. 2 to 3, the grounding device further comprises a self-locking pressing component 4, the self-locking pressing component 4 comprises a back plate 41, a crank component 42 and a pressing rod 43, the back plate 41 is vertically installed on the bottom plate 2, a crank fixing block 411 is arranged at one end, deviating from the bottom plate 2, of the back plate 41, the upper end of the crank component 42 is movably connected with the crank fixing block 411, the lower end of the crank component 42 is movably connected with the lateral portion of the back plate 41, the pressing rod 43 is installed at the lower end of the crank component 42, the crank component 42 drives the pressing rod 43 to move up and down, and the pressing rod 43 is located right above the grounding probe 13. Specifically, during the use, place the chip 100 that awaits measuring back in spacing frame 14, the artifical crank assembly 42 that drives of operating personnel glides along backplate 41, because crank assembly 42 upper end is articulated with crank fixed block 411 through the round pin axle, and lower extreme and backplate 41 sliding connection can be so that press stick 43 to be used on the chip 100 that awaits measuring, after the test is accomplished, the manual work make crank assembly 42 reset can, it is very simple and convenient to use. Moreover, it should be noted that, the force that prevents pressing rod 43 from acting on chip 100 to be tested is too large, and pressing rod 43 is provided with a stepped structure for cooperating with limit frame 14, and bar 43 is pressed in the joint, prevents that pressing rod 43 from continuously descending, crushes chip 100 to be tested.

As shown in fig. 3, the crank assembly 42 includes a crank arm 421, a crank block 422 and a mounting member 423, the crank block 422 is movably connected to the crank fixing block 411, one end of the crank arm 421 is movably connected to the crank block 422, the other end of the crank arm 421 is movably connected to the mounting member 423, a side portion of the mounting member 423 is movably connected to the back plate 41, and the pressing rod 43 is mounted at a lower end of the mounting member 423. Specifically, the crank block 422 is discoid, with crank fixed block 411 swing joint, and the crank arm 421 of V type passes through the round pin hub connection with crank block 422, constitutes the connecting rod structure to its lower extreme is connected with backplate 41 through installed part 423, makes crank arm 421 can only slide from top to bottom along backplate 41, ensures that the clamp plate 43 is located the chip 100 that awaits measuring directly over all the time, and to its perpendicular decurrent effort of exerting pressure. In order to avoid crushing the chip 100 to be tested, the lower end of the pressing rod 43 is provided with a rubber head.

As shown in fig. 3, a guide rail 412 is installed on the back plate 41 in the vertical direction, and a sliding block is disposed on a side of the mounting member 423, and the sliding block is movably connected to the guide rail 412 to play a role in limiting and prevent the mounting member 423 from deviating when moving up and down.

As shown in FIGS. 1-3, the connector 12 is a SMA radio frequency connector and a J30J connector. Specifically, the radio frequency signal passes through a 50 ohm coaxial transmission structure formed by the double-ended probe 13 and the microstrip line 31, and is connected to the SMA radio frequency connector through the microstrip line 31 on the second PCB 4. When the test device is used, the SMA connector is connected to a test instrument, the J30J connector is correctly connected to an external control board or a stabilized voltage power supply, the self-locking pressing component 4 is used for pressing the chip 100 to be tested, and finally, the control and current are connected to complete the test.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

The QFN packaging radio frequency chip test fixture is characterized in that: including mounting bracket and bottom plate, mounting bracket demountable installation is in on the bottom plate, surface mounting has first PCB board on the mounting bracket, mounting bracket internally mounted has the second PCB board, first PCB board with the one side that the second PCB board deviates from each other all is provided with the microstrip line, install double-end probe in the mounting bracket, the double-end probe both ends run through the mounting bracket, and respectively with microstrip line electricity on first PCB board and the second PCB board is connected, double-end probe with the microstrip line forms 50 ohm coaxial transmission conductors, the mounting bracket lateral part still is provided with a plurality of connectors, the connector with the terminal electricity of microstrip line is connected, mounting bracket upper surface middle part still is provided with earth probe and spacing frame, earth probe installs in the spacing frame.
2. The QFN packaged radio frequency chip test fixture of claim 1, wherein: still including auto-lock push down the subassembly, the auto-lock push down the subassembly includes the backplate, crank assembly and pressure stick, the backplate is installed perpendicularly on the bottom plate, the backplate deviates from the one end of bottom plate is provided with the crank fixed block, crank assembly upper end with crank fixed block swing joint, crank assembly lower extreme with backplate lateral part swing joint, press the stick to install crank assembly lower extreme, crank assembly drives press the stick displacement from top to bottom, press the stick to be located directly over ground probe.
3. The QFN packaged radio frequency chip testing jig of claim 2, wherein: the crank assembly comprises a crank arm, a crank block and an installation piece, the crank block is movably connected with the crank fixing block, one end of the crank arm is movably connected with the crank block, the other end of the crank arm is movably connected with the installation piece, the side portion of the installation piece is movably connected with the back plate, and the pressing rod is installed at the lower end of the installation piece.
4. The QFN packaged radio frequency chip test fixture of claim 3, wherein: the lower end of the pressing rod is provided with a rubber head.
5. The QFN packaged radio frequency chip test fixture of claim 3, wherein: the backplate is installed the guide rail along vertical direction, the installed part lateral part is provided with the slider, the slider with guide rail swing joint.
6. The QFN packaged radio frequency chip test fixture of claim 1, wherein: the connector is an SMA radio frequency connector and a J30J connector.