|
| Subscribe to the SMTnet Express |
|
|
|
| Link to SMTnet |
| Tell everyone you know about SMTnet! You can add this small image to your Web site and provide a link to us. Click here to learn how. |
 |
|
|
|
 |
bga Electronics Forums search results
4373 results found for bga in 4s.
Showing matching items 1 - 50
- 99%
Re: BGA Repair Problems - 8/17/98 -
- ... the surface should be allowed to cool for a couple of minutes. Re Balling BGA Devices To replace solder balls on to a BGA first all the uneven solder or solder balls should be removed using a conventional de soldering tool. When the surface of all the pads is flat either solder paste may be applied to the part, a liquid flux dispensed or flux paste stencil printed on to the BGA. A clean stencil is then placed on to the BGA and solder balls placed in the stencil. The over sized apertures allow ...
- 98%
BGA ball crack at pad/solder ball interface - 11/29/06 -
- BGA ball crack at pad/solder ball interface Dear all, Recently, we run 2 models with heat sink attachment on top of this BGA(on top of this BGA, there is flip chip attached at the center of the BGA). Hence, the center of the BGA is higher than corner/side. We used conventional way to attach heat sink to the BGA. Heat sink anchor pullout is a retention spring that press across the BGA package top surface and locks on both sides at the 2 hooks soldered to the board next to the edge of the BGA ...
- 98%
Number of thermal excursions per componet - 6/27/01 -
- ... product with reworked BGA. Others routinely replace the balls and re-use the BGA. [Here?s a take on Motorola?s thinking on repairing BGA. As a minimum => BGA Cycle 1: solder ball attach. BGA Cycle 2: BGA attach to board. BGA Cycle 3: BGA removal from board. BGA Cycle 4: BGA pad dress. BGA Cycle 5: BGA ball replacement. BGA Cycle 6: BGA re-attach to board. Board Cycle 1: BGA attach to board. Board Cycle 2: BGA removal from board. Board Cycle 3: board pad dress. Board 4: BGA re-attach to board ...
- 97%
Re: BGA's - Re-ball -- How thick? - 5/18/99 -
- ... BGA experiences... 1. REMOVE BGA, reball BGA, remove a ball from the BGA and replace it with a 30awg wire and protected using hi-temp solder and adhessive. Drill the pad all the way through the PWB, screen print solder paste using micro-stencil and placing BGA with the 30awg wire coming through the pwb. Reflow BGA using CONCEPTRONICS Freedom 2000 rework station. Attached 30awg wire to a via on solder side. X-ray and Ship. 2.Used the actual stencil to print solder paste on top of the balls of BGA ...
- 97%
BGA Reliability - 7/24/02 -
- ... or even the BGA substrate itself. We find many BGA's that look acceptable visually and through X ray inspection. Black pad contamination is not visually or X ray detectable. It causes the connection to appear as an open during electrical test. Many people misdiagnose it as a defective BGA component. You can only diagnose this problem by removing the BGA and inspecting the PCB & BGA substrates. I suggest that if you can use a QFP rather than a BGA, then do so. If you must use a BGA and have ...
- 97%
Re: BGA problem: open after reflow - 1/18/01 -
- ... Dave, The BGA substrate surface finish is NiAu, while the PCBA pad surface is HASL. The solder ball composition is SnPb 63/37 and the solder paste used on the PCBA is also the same but with 2% Silver.>>> Dave, sorry I don't have the picture with me now to post. After sodering the BGA on to the PCBA, we peeled off the BGA's subsrate which left the ball well in tact on the PCBA, and we analysed the surface left on the peeled BGA's subsrate pad. That was smoother than a raw BGA's removed ball by ...
- 96%
Water Soluble for No Clean BGA Balls - 4/13/04 -
- ... Soluble for No Clean BGA Balls Hi DaveF, To explain. The BGA that we have is from Motorola. The solder balls of these BGA's are Eutectic Solder and processed using a NC flux (as per info from supplier). So this means that the BGA pad and solder connections had NC flux process. We are applying WS paste on our PCB's then place the BGA's from Motorola with a NC processes bonding between the ball and bga pad. Though we are getting good solder joint and drop on our BGA's after reflow soldering, I'm ...
- 96%
Package on Package BGA Components any issue in SMT? - 3/14/07 -
- ... Package BGA Components any issue in SMT? Hi Muhammad thanks for the reply. However, this is my current situation. We are currently using some BGA's with this kind of packaging BGA over BGA. I have verified solderability of the main BGA (below Bga the one w/c will be soldered to PCB) using Ersascope inspection, X-ray inspection rotated 90 degree and also profile data's all is fine. However, during testing our ICT encounter's testing failures they simple use hot air to blow-up the BGA and retest ...
- 96%
Re:OK BGA-REWORK MACHINES OLD AND NEW - 1/31/00 -
- Re:OK BGA-REWORK MACHINES OLD AND NEW HELLO CUSTOMERS OF OK LATEST INFORMATION UPDATE WITH REFERENCE TO OLD BGA 2000 MACHINES WHICH ARE NOW 6YEARS OLD MANY NEW INVENTIONS WHICH HAVE TAKEN PLACE CAN BE PURCHASED FROM METCAL TO BRING YOU TO THE FOREFRONT OF TECHNOLOGY.(PATENTED TO ) BGA 3000 MACHINES HAVE BEEN REPLACED BY BGA 3500 SERIES, THESE DO GREAT SOLDER PASTE PREPARATION BY ALIGNING THE STENCIL ON THE MACHINE TO DO EFFORTLESS SOLDER PASTE APPLICATION FOR BGA AND CSP PRINTING. THE STENCILS ...
- 96%
Re: MicroBGA qualification process - 3/30/00 -
- ... plugged via under pad may also create a void in molten ball. Typically most voids are detected in the middle to top (ball / BGA interface) of the reflowed solder joint. This is expected because the entrapped air bubble and the vaporized flux, which is applied to the PCB BGA pads, rises during the reflow profile. This occurs when the applied solder paste and the BGA's collapsible eutectic solder ball(s) melt together during the reflow profile (typically 235 to 240 *C peak temperature). If the ...
- 96%
Bga reballing - 7/22/99 -
- Bga reballing Does anyone have any experiences with bga reballing. When I had reworked failed bga part with new part It was good. So I tried to reball bga detached but failed . I guess the cause of fail is thermal shock. IS IT OK TO REBALL BGA PARTS DETACHED ? I wonder. Before an experiment I'm sured that bga parts can stand thermal shock.The result was different as I expected THE PROCESS I DID IS AS BELOW ?? Detach an bga part failed with bga rework machine?? add heat ?? Remove residues with ...
- 96%
Solder reflow temperatures too high - 1/14/07 -
- ... BGA. * Using a syringe to dispense lots of a low melting point solder under the BGA. [Use an alloy with a MUCH lower than the near eutectic solder that you commonly use. Ask your paste supplier for suggestions. Try to avoid using alloys containing bismuth, because of potential reliability issues with high operating temperature equipment.] Then doing BGA removal. OR Remove the BGA by cutting the board, the dunking the BGA in a solder pot of near eutectic solder. ----> Pre-heating the board is now ...
- 96%
Functional Test Faulure due to BGA ICs - 7/21/06 -
- ... Test Faulure due to BGA ICs Does replacing the BGA fix the problem? To be a little more blunt, is the BGA or is it the tech says it's the BGA. Beleive none of what you hear and only half of what you see. What kind of BGA is it? If it is one of those BGA's with a built in heatsink, then the center balls may not be getting complete reflow. If it is a BGA with a flange, maybe the cool down is too fast and the BGA is warped during cool down. If you can sacrifice a PCB and BGA for profiling that ...
- 96%
Re-Balling BGA and BGA sockets - 1/15/99 -
- Re-Balling BGA and BGA sockets Does anyone have information pertaining to re-balling BGA components using balls that are preformed onto disolable paper waffers (mini BGA reballing kit)? The paper containing the specific BGA device/pattern would be placed onto the BGA then processed through a reflow (oven). After reflow, the BGA is placed in water and the paper containing the balls is pulled away from the component, resulting in a reballed BGA. Is this product available on the market or is it a ...
- 95%
BGA soldering & BGA ball formation - 11/17/08 -
- BGA soldering & BGA ball formation I would not recommend doing BGA soldering with only a hot air gun. I have done it in the past, but the boards would eventually come back from the field because the solder joints did not form correctly and the BGA would have to be reworked again. In the event that I had to solder a BGA without a BGA rework station, I would at least want to have a bottomside board preheater so that I could preheat the PCB before I applied topside heat with a hot air gun. When I ...
- 95%
BGA rework with unplugged vias PCB - 12/7/06 -
- BGA rework with unplugged vias PCB As you are aware the common method to rework BGA is : 1. Remove BGA with hot air reflow machine ( SRT as current practice) 2. Clean the BGA pad using solder iron and solder wick. 3. Replace BGA with SRT rework machine. The problem we have with unplug via is when we clean the BGA pad, the solder resist cover the trace between pads and vias will be removed. During the solder removal process certain amount of solder will also get into the unplug vias as well ...
- 95%
Re: BGA problem: open after reflow - 1/17/01 -
- ... from the BGA? Which reflow? What kind of balls? What pads? What pad solderability preservative? What solder? Hel-low-oh!!! When soldering the balls of a BGA to the assembly, I expect the ball to remain wetted to the [nickel plate over???] the copper pad on the BGA interposer. With a PBGA, like yours, I expect the ball will melt, collapse, and wet to the solderable surface on the assembly PCB. If you find the balls separating from the BGA, something is wrong, either with the BGA fabrication ...
- 95%
Need Expert Support - 3/13/01 -
- ... you generalities .did anyone do a DFM/DFT analisys?Are the bga's on topside only?Is it a mixed technology board?(SMTtop/smtbot/th/wave?)how many reflow cycles?In what order?Are the vias under the bga's tented ? (on both sides if boards are going over the wave)Are the bga pads isolated with solder mask? If this is a subcontractor you worked with before with good results do a quality run to find out where the trouble spot is. The bga's pitch and other mechanical caracteristics are available on ...
- 95%
Crystalized Flux under BGA - 8/4/04 -
- ... under BGA Hi, Thanks for your reply. I run 2 boards, using the same paste, thermal profile and the same method of aqueous cleaning, 1st is a Topline test board with topline BGA (BGA 272 with 1.27 Pitch) and the 2nd is our product PCB with our BGA from Motorola (BGA 272 with 1.27 Pitch). The test board BGA seems to be fine, clean and without any milky looking Joint. Our product's BGA looked milky and the white residue is noticeable below the solder joint as if there's a gap between the BGA ball ...
- 95%
Why is NC the prefer process for BGA mounting? why not WS? - 8/21/01 -
- ... process for BGA mounting? why not WS? 1) why is No-clean (NC) the preferred process, for BGA mounting by SMT? Probably the same reason NC is the preferred process for mounting non-area array SMT components. 2) why is water-soluble (WS) not a hot choice? There?s not reason not to use WS. Cleaning of assemblies featuring BGA devices may seem at first consideration to be fairly easy due to the large standoff height achieved by the balls. The difference between fine pitch QFP and BGA devices is that ...
- 95%
Re: BGA ball missing. - 8/30/98 -
- Re: BGA ball missing. Hi Kc! I went to Surface Mount International last week, and had a chance to see a way to reball BGA's that is very simple, and not expensive at all. I've seen the advertisements in a few magazines, but this was the first time I've seen it live. It's from a company called Solderquik, and they were re-balling BGA's at the show. It's a pre-formed array of balls that match the pattern of the device that you're "re-emasculating" (sorry, couldn't help myself...hehe ...
- 95%
Bridge on BGA - 8/18/99 -
- Bridge on BGA Yesterday as I was creating a profile on a plastic BGA using Conceptronics freedom 2000 rework station, I happend to discover that I was able to remove solder bridging from a plastic BGA. This is what I did. Created a removal profile, I had a board that had 3 bridges on the BGA. Run the profile and as soon as saw the BGA that was ready for removal, I brought down the nossle Picked up the BGA and came up almost 20mils than dropped back the BGA. I X-Ray the BGA, no bridging. The ...
- 94%
BGA flux dipping process - 6/2/09 -
- BGA flux dipping process We have been doing BGA's for years now, and I would suggest updating your profile and place a thermal couple on the BGA, keep in mind the bigger the part the more heat it will need, We stencil print all of BGA's from simple bga's to complex ones, your stencil provider if they know what they ware doing will be able to work with you on the stencil thickness. (DEK Rules), I also place BGA's without solder paste. Heres the most important trick to BGA's BAKE them first, they ...
- 94%
BGA inspection microscope - 12/6/05 -
- BGA inspection microscope There are quite a lot out there now: http://www.sapltd.co.uk/electronic_production/bga_scope/bga_scope.htm http://www.ocwhite.com/bga/ http://www.hirox-usa.com/bga.html BGA Reworking on the cheap? - 5/12/08 -
- BGA Reworking on the cheap? Hi, there are different BGA packages, it's not same to rework LFBGA with 0.5 mm step and BGA with 1.27 mm step for instance basically you will be able to de-solder the BGA with hot air and proper nozzle which distributes the heat even on the BGA package, your problem will be later to may place and solder the new BGA on the board to place precisely BGA part you will need machine with split vision or some tool which to allow you to place the chip on it's board location ...
- 94%
s Storage - 11/7/01 -
- BGA,s Storage 1 CAN WAVE SOLDER AFFECT OR DAMAGE BGA? Sure. Since you are vague, assuming: * Partially assembled board was not stored to prevent moisture absorption. * BGA is in a plastic package. * Partially assembled board was stored long enough to exceed the moisture absorption allowance of the BGA. * BGA is on the topside when waving. * Vias near the BGA pads are not plugged. So, here are a couple of possibilities: * Topside [and bottom side] temperature is ~200?F out of the preheater. Maybe ...
- 94%
BGA USAGE IN THE INDUSTRY? - 3/23/99 -
- BGA USAGE IN THE INDUSTRY? I WORK FOR A SMALL TO MID-SIZE CONTRACT ASSEMBLY HOUSE. WE ARE TRYING TO FIND ANY SURVEYS OR STUDIES DONE ON THE USE OF BGA'S BY COMPANIES ON NEW DESIGNS. THE WAY EVERYBODY'S ALWAYS TALKING ABOUT BGA'S YOU WOULD THINK THAT THERE WILL BE NOTHING EXCEPT BGA'S ON BOARDS 10 YEARS FROM NOW. NONE OF OUR CUSTOMERS AT THE TIME ARE USING ANY BGA'S. ANYWAY, MY MAIN QUESTION HERE IS IF ANYBODY OUT THERE KNOWS OF ANY STUDIES OR SURVEYS THAT BREAK DOWN THE MARKET ON PCB DESIGNS AND ...
- 94%
Re: Top Side BGA Reflowing @ Wave Solder - 10/11/99 -
- Re: Top Side BGA Reflowing @ Wave Solder | | | We've recently encountered this problem where one of our .050" pitch BGA's were reflowing at the wave thus causing shorts... The board was profiled with probes stuck to a QFP solder joint, an 0603, and one of the BGA joints. There was an almost 70 degree difference in peak temperature between the QFP and BGA solder joints!! The BGA joint was actually at liquidus for almost 10 seconds! | | | | | | What we needed to do was speed the wave conveyor up ...
- 94%
Re: Bga reballing - 7/26/99 -
- ... Does anyone have any experiences with bga reballing. | When I had reworked failed bga part with new part It was good. | So I tried to reball bga detached but failed . | I guess the cause of fail is thermal shock. | IS IT OK TO REBALL BGA PARTS DETACHED ? I wonder. | Before an experiment I'm sured that bga parts can stand thermal shock.The result was different as I expected | THE PROCESS I DID IS AS BELOW | ?? Detach an bga part failed with bga rework machine?? add heat | ?? Remove residues with ...
- 94%
BGA ball vs land design problem?? - 5/25/09 -
- BGA ball vs land design problem?? Hello, recently we changed supplier of the LF BGA, we did corossection and now have doubts... previous BGA specs : pitch 1mm, ball diameter 0.6mm future BGA specs : pitch 1mm, ball diameter 0.4mm on the crossecrion we found that one of the ball seems cracking from the package - under x-ray we saw void in other ball but this one seem quite normal, checking more BGA under x-rays show more voiding that on the opponent (previous) parts land pad on the PCB is 0.45 ...
- 94%
Stencil for BGA re-balling - 11/11/08 -
- ... Alternatives are: * BGA Reballing Preforms from SolderQuik [www.solderquik.com] Winslow Automation says it's fast, easy, and cost effective * Photo Stencil offers a universal BGA repair tool [www.photostencil.com/productlist.htm]. The tool holds the BGA package in place with a ball stencil registered to the holding tool. The entire tool, with balls in place, is sent through the reflow oven. * SMT Sales Associates [www.smtassociates.com] sells a fixture for reballing BGA one at a time. You apply ...
- 94%
BGA Tilt - 2/9/07 -
- BGA Tilt 0.25mm tilt? That's pretty small depending on you BGA size. Is it failing? Or just your Q.E. being anal? What size BGA we talking about? What ball count? Just one board? Maybe cheaper to just repair. Now assuming there is NO part under the BGA: First check your board. Are all pads the same size? Most board houses will cheat on pad openings. If not check your Gerber to be sure you are asking for same size on all pads. Next, check your part. Missing balls can cause tilt. Check your balls ...
- 94%
Very Low Volume BGA Assembly - 5/23/06 -
- ... We have seen little to no BGA scrap and we run 5000 units per year. I have worked for two other much larger companies in the 90s and we placed BGAs by the body. We even had a nice Air Vac BGA rework station. Never had to use it for BGA rework. We did not have an Xray machine and we used IR ovens back then. We used Dek 265s and Fuji IPs. It is my opinion that you do not need Xray or BGA rework equipment and you can still build a high quality product that uses BGA technology. Yes, when you run ...
- 94%
BGA Rework - 4/21/06 -
- ... the component and possibly damage it. If your BGA volume is very low, here is an alternative: Remove the BGA with hot air. Clean the pads. Purchase a small BGA stencil and squeegee. (google/yahooo for them, I can't remember off the top of my head) Squeegee the paste onto the board. Use your pick and place to put the BGA at the correct location and reflow. You could also remove the BGA with hot air, clean the pads. Apply tack flux, place the BGA by hand and reflow. Leaded BGAs will self-center ...
- 94%
Solid Solder Deposit - 8/10/04 -
- ... I agree 100% What kind of parts do you use for SSD? More specifically does your company use 0402, 0201, BGA's, etc? Also are the results of using SSD better than the normal process of applying soder paste? Also if anyone else uses SSD, what are your experiences with it? Thanks a lot. Check out the emails below from NASA concerning SIPAD BGA thermal cycleing as it relates to reliabilty of BGA's. A formal report is due out soon and will be available at Water Soluble for No Clean BGA Balls - 4/13/04 -
- ... for No Clean BGA Balls Q1: Can anyone explain to me about the effect of their mixture. A1: What is their ?mixture?? Q2: What enhancement does my BGA will have when using a WS paste flux with regards to corrosion, 25 years life cycle of the solder joint. A2: Tough to say, which board has the lower level of harmful contaminants? Q3: What's the benefit in using a WS paste flux on a BGA with No Clean solder joint process? A4: Assuming you solder NC / paste, reflow water washable BGA / wash, you get ...
- 94%
Pinhole Solder Joint Reliability - 7/22/03 -
- ... solder connection more often than other areas for two reasons - lower surface tension and largest area. BGA voiding is fairly well documented: * Google => bga void doe * Dr. Lee at Indium Corp. has conducted a number of investigations concerning solder joint voiding and BGA components. Check Indium's site. [As an aside, Lee's book "Reflow Soldering Processing and Troubleshooting SMT, BGA, CSP and Flip Chip Technologies" (Dr. Ning-Cheng Lee; Butterworth - Heinemann; 2002; ISBN: 0750672188) is ...
- 94%
BGA Rework - 4/9/03 -
- BGA Rework We've encountered a little problem with BGA's. There was a process problem in the build of the boards which has ment the BGA are failing open circuit due to the lack of solder paste. Any-one else had this problem? Any suggestions on solutions? We've tried replacing one BGA, but when the unit has been rebuilt and tested another BGA open circuit has been found on a different BGA. We also have the added problem of the boards being difficult in the sense we have to reflow the rework ...
- 94%
Help! BGA Socket / BGA Direct Placement - 11/14/02 -
- Help! BGA Socket / BGA Direct Placement Kevin, I have done the following process to a similar problem: 1. Plug holes (even to both sides of the board) 2. Clean any flux left on the surface, especially on bottom side. 3. Apply Kapton tape to the bottom side, you mite want to apply 3 layers. 4. Apply a small layer of paste flux to the top side. 5. Apply BGA and Reflow. Note: Applying paste flux will only work if attaching a plastic BGA with SN63/37. If you are applying a Ceramic BGA with SN 90/10 ...
- 94%
Re: BGA repair/rework - 3/7/99 -
- Re: BGA repair/rework | | | | | | | | I'm having a fun time between BGA rework/repair using an SRT 1000 and SPC efforts (much easier) using DEK stencil printing processes and BTU reflow with 6 Fuji lines in between. | | | | | | | | Concerning the BGA stuff, I'm getting about 60% success using this rework capability as being able to remove, place, and reflow 432 perimeter BGA's and others. This is unacceptable. I can remove or place and reflow two parts in sequence while the third does not budge ...
- 94%
Re: BGA's - Re-ball -- How thick? - 5/18/99 -
- ... you must end up with a 25-30mil balls when screen printing solder paste on your BGA component. Also I would recomend once removing the BGA from the boards, to cover vias with solder mask on the opposite side. This will ovoid for any solder migrating down to the VIA's. Also make sure to preheat your board since it will cause your BGA to colapse un-even. I have done the most amazing re-work on BGA's. BGA's ain't nothing THE AIN'T intimidated. | | Good luck... | | Tony | Wow, 25-30 mills can't be ...
- 94%
Re: Bga reballing - 7/26/99 -
- Re: Bga reballing | Does anyone have any experiences with bga reballing. | When I had reworked failed bga part with new part It was good. | So I tried to reball bga detached but failed . | I guess the cause of fail is thermal shock. | IS IT OK TO REBALL BGA PARTS DETACHED ? I wonder. | Before an experiment I'm sured that bga parts can stand thermal shock.The result was different as I expected | THE PROCESS I DID IS AS BELOW | ?? Detach an bga part failed with bga rework machine?? add heat ...
- 94%
Re: Bga reballing - 7/22/99 -
- Re: Bga reballing | Does anyone have any experiences with bga reballing. | When I had reworked failed bga part with new part It was good. | So I tried to reball bga detached but failed . | I guess the cause of fail is thermal shock. | IS IT OK TO REBALL BGA PARTS DETACHED ? I wonder. | Before an experiment I'm sured that bga parts can stand thermal shock.The result was different as I expected | THE PROCESS I DID IS AS BELOW | ?? Detach an bga part failed with bga rework machine?? add heat ...
- 93%
BGA Information Needed - 7/14/98 -
- BGA Information Needed I am looking for some general information with respect to BGA devices on circuit boards. I work for an automation company and am curious to know who's doing what with BGA placements, specifically the heat - sink application to the BGA device. Generally, are heat sinks added to the bga prior to or after assembly on to the board? How many bga devices are there typically on a board? What through-put (production) rate is typically reqired; i.e. boards produced per hour? I ...
- 93%
BGA soldering Problem - 11/24/08 -
- ... reflow profile is peaking at 245 but we are seeing around a 10% failure rate with the BGA package with dry joints. The PCB has a very large unbroken ground plane on the outer layers, though not under the BGA. Will this affect the BGA soldering? Should I cut it back around the BGA. All the Atmel BGA packages listed on the Atmel website specify that the ball composition is 95.5% Tin, 4% Silver & 0.5% Copper
- 93%
BGA soldering problems - 11/24/08 -
- ... reflow profile is peaking at 245 but we are seeing around a 10% failure rate with the BGA package with dry joints. The PCB has a very large unbroken ground plane on the outer layers, though not under the BGA. Will this affect the BGA soldering? Should I cut it back around the BGA. All the Atmel BGA packages listed on the Atmel website specify that the ball composition is 95.5% Tin, 4% Silver & 0.5% Copper
- 93%
Lead-Free BGA Rework - 6/26/07 -
- Lead-Free BGA Rework I have been trying to rework a lead-free BGA. For some reason, when I remove the BGA the corner pads on the board come off and the board must be scrapped. If I do manage to remove the BGA successfully, when I solder the BGA, the corners of the BGA warp up and doesn't allow me to get a good connection on the pads. I have tried using a larger nozzle, increased temperature, and nothing seems to work. the board is ENIG and it does contain a large ground plane ...
- 93%
BGA opens / cracks - 1/24/07 -
- BGA opens / cracks Hello, we are facing some troubles with BGA opens in our production. PCB are both side popolated with BGA. BGA is array of 26*26, with some 6*6 center balls. PCB has 2 reflow processes, 4 pcs of BGA on each side. Now we are partly observing opens on the center balls on those BGA which have seen 2nd reflow process. Cross section analysis have shown micro cracks between ball and BGA pad. No crack between ball and PCB pad. Ball itselfs looks good, and also was soldered before on ...
- 93%
Solder reflow temperatures too high - 1/11/07 -
- ... melting point solder? R: Not that we know of. J: We would like to re-use the component some of these hard to find BGA, but the high reflow temperatures are damaging the BGA during the removal process. R: Try doing both of the following: * Preheating the board at 125*C prior to considering removing the BGA. * Using a syringe to dispense lots of a low melting point solder under the BGA. [Use an alloy with a MUCH lower than the near eutectic solder that you commonly use. Ask your paste supplier for ...
- 93%
BGA adapter boad? - 1/5/07 -
- BGA adapter boad? I have a customer working on a new design of a rather large board that needs to use a micro BGA that will require 8 layers. He needs to use that BGA and it does not come in any other package. He asked me about making the BGA an adapter or daughter board so he could make the rest of the board 2 or 4 layer to keep the cost down. This would also eliminate the need to do micro-BGA level rework. The part would be attached to a small board with a grid of round pads on the bottom side ...
Results
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
|
|
Back to the Top
