CN104006999B - Supporting fixture of drop test PCB - Google Patents

Abstract

Belonging to the material test field, the invention relates to a drop test PCB and a supporting fixture thereof. The drop test PCB comprises a cube-shaped PCB (1). Daisy chains (2) are arranged at the middle position of each edge of the square. The lead wire diameter (4) of the daisy chains (2) and the solder ball diameter dimension are approximately identical. Starting and ending solder pads of the lead wires (4) of the daisy chains (2) are located at the middle positions of the PCB (1). Four corners of the PCB (1) are equipped with holes (5) for fixing the PCB (1) on a drop table. The supporting fixture is simple to operate, and can reduce working intensity and ensure test repeatability and stability.

Description

A kind of matched fixture of drop test pcb plate

Technical field

The present invention is that a kind of board-level drop test pcb plate that is used for designs, and grinding and polishing sample preparation and microstructure observation's process In for fixing the matched fixture of pcb plate, belong to testing of materials field it is adaptable to solder joint during access panel level drop test Germinating, extension and disconnection process, are applied to the reliability consideration with regard to drop test in Electronic Packaging.

Background technology

For presently, the update speed of electronic product, considerably beyond the use time of consumer, passes The failure modes such as the creep being caused due to heat, electricity, magnetic etc. of system, fatigue have been no longer the major concern factor of production firm.And Vibration and fall for avoiding completely during transport and use, often in transportation produce vibration and make With during produce accident fall be impact the electronic product life-span key factor.

Drop test is often divided into Product-level, plate level and three kinds of method of testings of joint level.Product-level test is often used for making Make manufacturer and test its anti-dropping capability after the completion of actual electronic product produces, evaluate in the actual life falling aspect, For improving the integrally-built design of electronic product；Plate level and the test of joint level are then primarily intended to laboratory research solder joint not With the inefficacy mechanism and the biometry that fall under environment, but joint level drop test only focuses on the inefficacy mechanism of single solder joint, suddenly Omit the relatedness of actual product, therefore board-level drop test is the main direction of studying of numerous scholars.In order to ensure research knot Fruit to other scholars, there is referential, jcdec formulated detailed fall-down test standard in 2003, for the shape of pcb plate, Size, bga position are described in detail, but its standard has certain limitation to experimentation, are unfavorable for observing The failure mode of solder joint diverse location in falling process, mainly observes the failure procedure of solder joint by the signal of telecommunication, leads to learn Person's undue impact paying close attention to mechanics butt welding point in research process, the performance ignoring material itself to the effect falling the life-span, and And in simulation process, actual experimental verification is relatively fewer.In order to study inefficacy mechanism under plate level level for the solder joint and material Relation between material, is a kind of indispensable direction improved to biometry accuracy.Therefore, design one kind can be observed The pcb plate of solder joint failure process, becomes one of critical problem of board-level drop reliability consideration.Because pcb plate thickness is thin, face Long-pending big feature, is unfavorable for putting in grinding and polishing and Electronic Speculum test process, and the mainly method by inlaying sample solves, and this is just The integrity of pcb plate can be destroyed it is impossible to ensure the home position observation of actual solder joint, a kind of grinding and polishing beneficial to pcb plate of design, observation Matched fixture, is also to need one of key issue of solution.

Content of the invention

The present invention is the technological deficiency that problem to be solved is for overcoming foregoing description, is ensureing that board-level drop test will In the case of asking, design is a kind of can to observe pcb plate and its matched fixture that solder joint observes failure procedure in falling process.

A kind of drop test pcb plate and matched fixture it is characterised in that: pcb plate 1 is square, foursquare each Daisy chain 2 is all arranged in the centre position on individual side, and the diameter of lead 4 in daisy chain 2 is with the diameter dimension of soldered ball close to equal, institute State beginning of lead 4 in daisy chain 2, terminal pad 3 is located at the centre position of pcb plate 1, four angles of pcb plate 1 are disposed with For the hole 5 being fixed on pcb plate 1 on dropping table；The matched fixture of pcb plate includes grinding and polishing fixture and Electronic Speculum detection clamp, mill Throw fixture and include upper face 6 and lower face 7, both are connected by hinge 15；Groove iii9 is located at the left side interposition of lower face 7 Put, groove iv10 is located at the upside centre position of lower face 7, groove iii9 and groove iv10 size and encapsulation on pcb plate 1 Bga is that ball grid array structure is equivalently-sized, and groove i11 is located at the centre position on the right side of lower face, and groove ii12 is located at lower plate The centre position of the downside in face；Groove i11 and groove ii12 is rectangle, the vertical direction size of groove i11 and groove ii12 Less 1 millimeter than encapsulation bga, external part i13 is located at the left side of lower face 7, and external part ii14 is located at the upside of lower face 7, screw 8 Positioned at grinding and polishing fixture lower right, it is screwed connection upper face 6 and lower face 7；

Electronic Speculum detection clamp bottom is made up of cuboid and two circular arcs, is uniformly distributed 10 draw-in grooves above cuboid 16, draw-in groove size disclosure satisfy that the pcb plate of encapsulation bga vertically inserts in draw-in groove.

The size of described pcb plate 1 is 41mm*41mm*0.5mm.

The present invention can obtain following beneficial effect: the pcb plate of present invention design can be used in solder joint on research pcb plate and exists The germinating of crackle in falling process, extension and disconnection, design is simple, beneficial to laboratory science research, its matched fixture, grinding and polishing card Tool ensure that consistent level during grinding and polishing for the entire row solder joint on pcb plate, and the plastic deformation of minimizing pcb, and grinding and polishing is imitated Rate is high, simple to operate, reduces working strength and the repeatability and the stability that ensure experiment, and Electronic Speculum detection clamp can not damage The observation of butt welding point microscopic structure is completed, it is many that it once observes sample size in the case of bad pcb plate.

Brief description

Fig. 1: pcb plate structure schematic diagram；

Fig. 2: grinding and polishing fixture structure schematic diagram；

Fig. 3: grinding and polishing fixture rearview

Fig. 4: Electronic Speculum detection clamp structural representation；

In figure: 1-pcb plate, 2- daisy chain, 3- begins, terminal pad, 4- lead, 5- hole, 6- upper face, 7- lower face, 8- Screw, 9- lower plate groove i, 10- lower plate groove ii, 11- lower plate groove iii, 12- lower plate groove iv, 13- lower plate external part i, 14- lower plate external part ii, 15- hinge, 16- draw-in groove.

Specific embodiment

A kind of drop test pcb plate, it includes pcb plate 1, and described pcb plate 1 is square, a size of 41* 41*0.5mm, all arranges daisy chain 2 in the centre position on each side foursquare, diameter wire 4 and Diameter of Solder Ball in daisy chain 2 It is closely sized to the equal described beginning of daisy chain 2 lead 4, terminal pad 3 is located at the centre position of pcb plate 1, the four of pcb plate 1 Hole 5 for being fixed on pcb plate 1 on dropping table is disposed with individual angle.Matched fixture includes grinding and polishing fixture and Electronic Speculum test card Tool, grinding and polishing fixture includes upper face 6 and lower face 7, and both are connected by hinge 15.Lower plate groove iii9 and lower plate groove iv10 Positioned at left side and the upside of lower face 7, size is equivalently-sized with encapsulation bga ball grid array structure bga on pcb plate 1, lower plate groove I11 and lower plate groove ii12 is located at the right side of lower face 7 and the centre position of downside, is rectangle, the size ratio of vertical direction Bga is little 1 millimeter for encapsulation, and lower plate external part i13 and lower plate external part ii14 is located at left side and the upside of lower face, puts positioned at bottom right Screw 8, be screwed connection upper and lower plate face.Electronic Speculum detection clamp bottom is made up of cuboid and two circular arcs, is growing It is uniformly distributed 10 draw-in grooves 16, draw-in groove size disclosure satisfy that the pcb of encapsulation bga vertically inserts in draw-in groove above cube.

Specific operation process:

Pcb plate 1 as shown in Figure 1 can circuit diagram and size manufacture directly to production firm, by finished product as described above Pcb plate encapsulates bga, is installed according to grinding and polishing fixture shown in Fig. 2, backs out screw, opens upper face 6, lower face 7, allows bga to seal Dress faces down, and puts into it is ensured that pcb plate is fully horizontally placed on lower face 7 in grinding and polishing fixture, bga and lower plate groove i9 lower plate Groove ii-10, lower plate groove iii11, lower plate groove iv12 mate completely, and both sides are stretched with lower plate external part i13 and lower plate Go out to hold ii14 level connection joint, be screwed upper and lower plate face it is ensured that being horizontally arranged in grinding and polishing fixture of pcb plate；Grinding and polishing is complete Cheng Hou, it is ensured that grinding and polishing face is not had with Electronic Speculum test fixture in the Electronic Speculum detection clamp structure that pcb plate is inserted in as shown in Figure 4 There is any contact, Electronic Speculum detection clamp put into and is scanned in sample stage testing, observe the primary morphology of soldered ball microscopic structure, Afterwards, pcb plate is accessed on drop test platform, carry out drop test, in conjunction with the signal of telecommunication, when finding to crack germinating, then Take off pcb plate, put in Electronic Speculum detection clamp, observe the change of crackle in displaing micro tissue topography, and so on, until bga is complete Complete lost efficacy, can thoroughly observe the germinating of solder joint crackle, extension, disconnection during this.

Claims (2)

1. a kind of matched fixture of drop test pcb plate it is characterised in that: pcb plate (1) be square, foursquare each Daisy chain (2) is all arranged in the centre position on side, and the diameter dimension of the diameter of lead (4) in daisy chain (2) and soldered ball is close to phase Deng beginning of lead (4) on described daisy chain (2), terminal pad (3) are located at the centre position of pcb plate (1), in pcb plate (1) Four angles on be disposed with hole (5) for being fixed on pcb plate (1) on dropping table；The matched fixture of pcb plate includes grinding and polishing card Tool and Electronic Speculum detection clamp, grinding and polishing fixture includes upper face (6) and lower face (7), and both pass through hinge (15) and connect；Groove Iii (9) is located at the left side centre position of lower face (7), and groove iv (10) is located at the upside centre position of lower face (7), groove Iii (9) and groove iv (10) size are that ball grid array structure is equivalently-sized with the bga of the upper encapsulation of pcb plate (1), groove i (11) position In the centre position on the right side of lower face, groove ii (12) is located at the centre position of the downside of lower face；Groove i (11) and groove Ii (12) is rectangle, and the vertical direction size of groove i (11) and groove ii (12) is less 1 millimeter than encapsulation bga, external part i (13) it is located at the left side of lower face (7), external part ii (14) is located at the upside of lower face (7), and it is right that screw (8) is located at grinding and polishing fixture Lower section, is screwed connection upper face (6) and lower face (7)；

Electronic Speculum detection clamp bottom is made up of cuboid and two circular arcs, is uniformly distributed 10 draw-in grooves (16) above cuboid, Draw-in groove size disclosure satisfy that the pcb plate of encapsulation bga vertically inserts in draw-in groove.

2. a kind of drop test pcb plate according to claim 1 matched fixture it is characterised in that: described pcb plate (1) Size be 41mm*41mm*0.5mm.