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1. How you inspect the issue of void in PTH mainly associated with PCB fabrication?

Generally in nowadays, most of PTH is processed by laser drilling techniques in which during its process can easily generate the skew surface to the barrel of the PTH which in turn can furthermore affect the quality of copper plating being adhered upon the barrel of the PTH in resulting that is so called “void in PTH (Plated Throu Hole)”. In addition, the quality of E-test continuity associated with PTH is determined by the tiny variation of resistance contained within of it, only by enforcing the criteria of micro-ohm in testing the quality of E-test continuity associated with PTH is must and has to meet the variation of resistance of the PTH as good as lower than 0.01Ω no doubt. There is another method approach which can prevent those PCB having void in PTH hole, leaking to your customer end that can jeopardize the product quality reputation of your company. That is by using the experimental feasible application of power energy proposed by ANPS in which can break open to any PTH having void condition due to the poor hole laser drilling process that in turn creating the uneven surface effecting the accuracy of copper plating. That way your customers would never have to deal with those PCB contained of void in PTH hole which is doomed of having bad E-test continuity issue later on.      Go (1)      Go (2)

 

2. How you inspect the slightly differentiation associated to the thickness of copper plating of a pattern on PCB?

"Micro-Open" issue associated to circuit patterns or P.T.H. is not merely caused by the cut on or among the circuit patterns on the PCB it also can be occurred due to the poor manufacturing process in resulting to insufficient thickness of copper plating applied upon circuit patterns on PCB. As we all know PCB Open/Short testing (E-Test) is targeted in inspection to the resistance of circuit patterns upon whole PCB therefore the minor variation of the increasing to the resistance of circuit patterns occurred due to the insufficient thickness of copper plating can only be found out by 4W PCB Open/Short approach.      Go

 

3. Why some PCB got passed at the manufacturing line but found open circuit pattern at customer side?

There are several facts associated with the PCB manufacturing process in which can come up poor continuity quality in regarding to the circuit patterns and PTH on PCB. This kind of PCB with bad quality of continuity to circuit patterns and PTH on PCB can later on fail at the PCB assembly house simply due to cracking phenomenon appeared and found on the circuit patterns or PTH after heat-up re-flow process. Normally general O/S tester that you can simply pick up from the general market now cannot prevent or detect out those weak circuit patterns or PTH during normal the E-test process it functions. However there is where ANPS come in the picture proposing the theory which is quite simple. Pleaser just try to imagine that it is like you pull harder on both end of a thread in attempting to make sure is the thread firmly enough to withstand any possible stronger pulling? Same ideal applied to the circuit patterns and PTH on PCB, we intend to test out the reliability of the circuit patterns and PTH on PCB as well as by applying stronger power energy, which is designed in 10 different levels, to have it run thru circuit patterns and PTH just to further determining that fact that can we possible bust it out chances are if we can then it proves that some circuit patterns and PTH are weak and this PCB is categorized as defective one and shouldnt be delivered to the PCB assembly house as you can possible guess here.      Go

 

4. How you find out those circuit patterns having open phenomenon experienced by theGalvanic Effect?

Technically, the particular characteristics associated with of electroplating process applied with PCB manufacturing fabrication process the connecting junction between PAD and RING would easily produce a tiny cut-open gape this phenomenon is well known as of the so-called Galvanic Effect. While conducting electroplating process unless the cut-open gape maintaining a certain length of gap otherwise there is no way that a general common Open/Short tester can have it disclosed out and put it in the defective spot light. The only way out of it is to apply the technical application of conducting power energy run thru those connecting junction where is between PAD or RING and circuit patterns to see can this applied technical approach bust out those weak connecting junctions in order to assure the reliability of this area.      Go

 

5. Do you know the void in annular rings on the PCB often causing PCB tester failed on circuitry continuity testing?

Due to the nature of copper it is in lack of the needed extensive stretching capability while the manufacturing process of electro-copper-plating associated to PCB fabrication. The void in annular rings is expected and often found on the inner barrel of via holes (PTH) on PCB. Normally as we all know that there is up-down compressing machine movement associated with any BBT (Bare Board Tester) machine while conducting Open/Short E-test therefore it causes those voids (broken) in annular rings to be pushed together again which in resulting of putting those once disconnected area back to be connected again and get pass condition from the later on E-test procedure since most of BBT machine only apply 10Ω circuit resistance criteria for continuity test . As you can possible guess those are too weak to withstand in the hit-up re-flow process to be disconnected back to square onethat was supposed to be detected out at first place that we often see in PCB Assembly house. This kind of issue should only be dealt with ANPS-2B which is by applying power energy run thru to break up the weak connecting resulted from up-down compressing movement associated with BBT (Bare Board Tester) machine.      Go

 

6. How do we effectively reduce the rate of reimbursement payment to the your depressed customers?

ANPS-2B can send energy power, which is designed and adjustable into 10 different levels, thru circuit patterns and via holes (PTH) on PCB in order to insure the withstanding reliability of patterns and PTH associated with PCB. The ideal is wed exam every PCB, before that PCB is tested for circuit Open/Short by any type and brand of BBT machine that you commonly find in the market , by doing so we can then pick up those PCB with possible suspected micro-open phenomenon and mark them as defective PCB before E-test that way we can guarantee to reduce the defective PPM rate low than whatever the prior defective PPM rate was because once when a PCB is passed by ANPS-2B for good circuit withstanding reliability it can pretty much be assured that the withstanding capability of circuit patterns and PTH on the PCB has met its strict standard. Simply by doing the math for your good sake, supposed every month your company will have to reimburse your customer US$6,000 because of micro-open issue occurred to circuit patterns or PTH later on found out at the PCB assembly house after the components being populated after re-flow process. The whole year you will end up paying up the grand total of US$ 72,000 of reimbursement to your unhappy customers not to mention the invisible damage of business reputation. Actually this is our goal of making sure every PCB delivered to your customers as less possible defected as we can possible offer you.      Go (1)      Go (2)      Go (3)

 

7. What are the BBT that ANPS carries in line equipped with the capability of low-ΩOpen/Short testing criteria?

Among ANPS BBT machine series either Universal-Type or Dedicate-type all equipped with the capability of 4-W open/short micro-Ω spec. both types are all capable of reaching circuit resistance as low as 0.1Ω for continuity in addition to the dedicate-type BBT can even reach the circuit resistance as lower as of 0.001Ω for continuity testing, this is break-thru technology for PCB Open/Short testing around the world.      Go (1)      Go (2)      Go (3)     

 

8. Why we see the trend of strong demanding for micro-Ωtesting spec requested to have it equipped with BBT machines either dedicated-type or universal-type from the customers in the PCB mess manufacturing fabrication industry?

As we all are aware of that 3C electronic consuming products are getting smaller each time we check, getting smaller for a 3C final product will mean the smaller circuit designing of patterns and PTH on the PCB as well. In the old time the sizing of 3C final product was not the major and sensitive concerning as the marketing strategy pitch to the end users, therefore most of PCB manufacturing fabricators would not mind as well as not intend to adopt as high as 50Ω circuit resistance as criteria for continuity testing for they concern as long as the circuit resistance stays as low as 50Ω a PCB should be considered as possessing good qualify in respect to continuity condition for patterns and PTH associated with a PCB. However, since now a tiny variation of circuit resistance associated with patterns and PTH on PCB is far importance considered than ever before due to the rising demanding and requirement for new designing trend of 3C final products as you can see listed below:

Speed of CPU has to be fastening than ever Promoting the clock circle of pulse frequency Reducing the working voltage associated with CUP (Before 5V 3.3V 2.8V 1.5V) Low down power energy demanding Reducing quantity of consumed power being wasted .      Go (1)      Go (2)      Go (3)

 

9. Why Black-out zone area is shown after O/S testing?

Due to the insulation circuit testing procedure that it would generate the carbonization phenomenon which is so-called of the Black-out zone appearance.

 

10. Why once the PCB is tested and received PASS condition and then immediately test the same PCB again but receiving FAIL condition instead?

That's because the carbonization phenomenon, which is the common phenomenon usually right after insulation circuit testing, got in the way, ANPS has successfully developed the new techniques and had it equipped into all type of BBT machines, either dedicate or universal type, that ANPS currently carries in-line which can effectively prevent this kind of carbonization phenomenon from happening.      Go (1)      Go (2)      Go (3)     

 

11. Based on your professional advice what will be the appropriate pin base design, the card -type and soldered- type?

Card-type designed-pin base is more convenient to be manufactured on the view of BBT machine suppliers and also the cost is far more lower if you compared the cost in respect to soldered-type designed-pin base BBT machines. Card-type pin base designing has less advantage to end users in fact end users would end up spending more money for maintenance for example if there is a single probe pin among the IO card being found affected with oxidized appearance, the end users would have to replace the whole IO card, even the rest of probe pins are considered in fine condition with a brand new one. Furthermore, in some cases, end users would be required to send the whole IO card back to the original BBT supplier for replacement. Also since there is more contact points in respect to the whole IO card therefore the more contact resistance are considered it will be on a single IO card which in turn can't satisfy the 4-W micro-ohm circuit resistance specs. Likewise, the soldered-type pin-base designing is easy to be maintained, for the end users there is no need to replace the whole IO card simple replace a single defected probe pin if found defective with whatsoever reasons and in addition soldered-type designed pin-base can satisfy 4-W micro-ohm continuity testing since there is less contact resistance involved with it.      Go (1)      

 

12. Can ANPS support this kind of PCB Open/short mechanism assuming customers prefer to have several different circuit resistance sets and which are targeted to some unique particular designed pattern net-works?

Due to there are more and more demanding from PCB Assembly house upon requesting even lower circuit resistance targeted to some particular pattern net-works among general pattern net-works on PCB, therefore youll need to have a BBT designed in committing to complete the Open/Short testing, in which having general Open/Short and 4-W Micro-Ohm Open/Short testing performed all together as same time, that way youd never have go thru twice Open/Short testing procedures, one is for those general pattern net-works and another is aimed for those special pattern net-works that can only be detected out by 4-W Micro-Ohm Open/Short testing approach.      Go (1)      Go (2)      Go (3)     

 

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