ICT夹具故障处理.doc

Troubleshooting, repairing, and maintaining fixtures夹具的故障解决，修理和维护 This chapter contain information about troubleshooting fixtures for the most common problems encountered. Repair procedures follow troubleshooting tactics. This chapter also describes the recommended maintenance procedures to keep your fixtures operating properly over their full lifetime. 此章包括了在夹具上遇到的大多数普通的问题的解决。在故障发现之后就是修理过程。本章也描述了推荐的维护程序，以保持夹具在整个使用过程中工作顺利。14.1 TROUBLESHOOTIING AND REPAIRING YOUR FIXTURES 发现夹具问题并修理夹具 The information presented here will help you solve most fixture problems whether they occur when the fixture first built or after the fixture has been in use for some time. First the problem is listed in the section heading, followed by possible causes and ways to fix the problem. 在这里介绍的情况将帮助你解决大多数的夹具问题，不论是在第一次做夹具的时候还是夹具已经使用了一段时间。 首先问题在每段开头列出了问题， 接着是可能的原因，以及解决问题的方法。14.1.1 The Board Does Not Sit Flat On The Gasket 主板在垫圈上不能平放 1.This can be caused by components or component leads on the bottom side of the circuit board contacting spacers, gasket material, or the support plate itself. To fix this, you can move the spacers or gasket material, trim the leads, or cut a relief slot into the support plate. 这可能是由于在电路板底边的元件或元件引脚接触到了隔板，衬垫材料，或者是支撑板本身。为了解决它，你可以移动隔板或衬垫材料，修整引脚，或在支撑板上切割一个减压槽。 2. This can also be caused by uneven placement of probe; that is , more probes on one side of the board than the other. This can be especially true when connectors or high density components are probed. You can fix the problem by putting low force probes in these high probe density areas. Fixturing software takes probe density into consideration on the HP SimPlate Express fixture and recommends the use of low force probes in high density areas. However , the software doesnt know probe locations on an HP SimPlate fixture; therefore, you will have to determine when and where to use low force probes. If the problem persists, you can also add HP PreLoaded Springs near the problem area as explained in chapter 8. 这也可能是由于探针的不平整的放置，也就是说，在主板上一边的探针比另一边的多。当连接器或者高密度的元件被探测的时候尤其可能发生。你可以在那些高密度的探针区域放置低压力的探针来解决问题。夹具软件在HP SimPlate Express夹具上考虑到探针密度，推荐在高密度区域使用低压力探针。但是，软件不知道在一个 HP SimPlate夹具上的探针排列。因此 ，你不得不决定何时何地使用低压力探针。如果这个问题还存在，你也可以象在第8章说的那样在问题区域增加HP PreLoaded弹簧。 3. Another cause could be lack of vacuum pressure or air-flow capacity. See chapter 11 for these requirements. 另一个原因可能是缺乏真空压力或气流容量。查看11章解决问题。4. Improper positioning or not enough spacers can also cause this problem. To fix it, add more spacers to the low areas of the circuit board. Also, be sure that the spacers are not placed so that they interfere with components or component leads. 不恰当的放置或没有足够的空间间隔也可能导致这个问题。为解决它，在电路板的底部区域增加更多的隔板。同时，确定那些隔板并没有放置在影响元件或元件引脚的地方。5. Excess gasket material under the circuit board can also cause this problem. Only 3.2 millimeters (0.125 in.) of gasket material should underlap the board. 在线路板下有过多的垫圈材料也会导致这个问题。只能有3.2毫米（0.125英寸）的垫圈材料能从板底露出。14.1.2 The Board Will Not Pull Down Far Enough电路板下拉不充分1. This can be caused by insufficient vacuum pressure or air-flow capacity. Be sure that your vacuum system meets the requirements specified in chapter 11. 这可能由真空压力或者气流容量不够引起。确保你的真空系统达到了11章需要的标准。2. This can also be caused by a vacuum leak due to a worn or improperly installed circuit board gasket or HP Spring Seal. The leak is usually very noisy and can be located by running your fingers around the edge of the board and support plate after vacuum is applied. You will be able to either feel the suction or hear a change in the noise made by the leak when your fingers contact the leak area. To repair these kinds of problems, refer to chapter 8.这可能的原因是，由于用旧的或不正确安放的电路板垫圈或HP弹簧封口导致的真空泄漏。泄漏经常噪声很大。在真空加上后，可以通过将你的手指在板和支撑板的周围移动来确定泄漏的位置。当你的手指接触到泄漏区域的时候，你将能感受到由于泄漏产生的吸力或听到声音的改变。要修理这些问题，参考第8章。3. An obstruction on the underside of the support plate or between the board and support plate can also cause this problem.在支撑板的下面有堵塞物或在支撑板和电路板间有堵塞物也可能导致这个问题。4. Tooling pins binding on either the support plate or the circuit board can also cause this problem by not allowing the board or the support plate to travel down far enough to seal properly. Using a small tri-square, inspect the fixture for bent or crooked (non-vertical) tooling pins, and straighten or replace them as necessary. If you must straighten tooling pins, be sure to bend them at the base, not in the middle.在支撑板或者电路板上装订的加工插脚，由于不允许电路板和支撑板下压足够深来吻合完全，也可能导致这个问题。使用小的曲尺检查夹具上的弯曲或扭曲的加工插脚，必要时弄直它或替换它。如果你必须弄直加工插脚，要在他们的基部弯曲，不要在中间弯曲。5. If the probes push the board off the gasket on the way down (as vacuum is applied), this is an indication of improperly placed or lack of HP PreLoaded Springs. See chapter 8 for more information about the use of springs.如果探针在下降时（当真空加上时）将板推离垫圈，这就说明HP PreLoaded弹簧的放置不正确或缺少HP PreLoaded弹簧。查看第8 章，获得更多使用弹簧的资料。6. A concentration of high-force probes could also cause the problem. To fix this you could add HP PreLoaded Springs, or you could also replace some of the high-force probes with low-force probes.高压力探针的集中也可能导致这个问题。要解决它，你可以增加HP PreLoaded 弹簧，或者你也可以用一些低压力探针代替高压力探针。14.1.3 The Board “Pops Off” When Vacuum is Released当真空释放的时候，电路板弹离夹具This happens because the circuit board is pushed upward by the probe forces faster than the support plate moves upward. You can solve the problem by adding HP PreLoaded Springs, low force probes in high density areas, or both. HP DuraDam material can sometimes keep this problem from occurring in the first place. 发生的原因是：线路板被支撑板向上推，而探针的上推的压力比支撑板更快 . 要解决它，你可以在高密度区域增加HP PreLoaded 弹簧，或低压力弹簧，或同时使用两者。HP DuraDam 材料在问题第一次发生的时候有时可以阻止它发生。14.1.4 HP Spring Seal is Pulled Under the Support Plate HP Spring Seal 被支撑板拉下来1. This can be caused by contamination of the low-tack adhesive. Replace the adhesive with Hi/Lo Tack tape supplied in the HP 44200K Spare Parts Kit.可能由于少量附加的粘合剂的污染。用HP 44200K空余零件箱中的Hi/Lo Tack tape替换粘合剂。2. This can also be caused by an obstruction holding the support plate up.也可能由于阻塞物阻挡了支撑板3. Too much vacuum pressure can also be the source of this problem. Either regulate or reduce the vacuum pressure into the system.真空压力过多也可能导致这个原因。增加或减小系统真空压力。4. If the Hi/Lo Tack tape was replaced without removing the adhesive residue left behind by the previous tape, then this residue can act as a lubricant to the new adhesive. When replacing tape, always remove the old adhesive residue, if there is any, before attaching the new tape.如果没有清除掉前面一条带子残留的粘合剂就替换Hi/Lo Tack tape，那么残渣将会象润滑剂一样对粘合剂作用。替换带子的时候，贴上新的带子之前，如果有任何的的粘合剂残渣，要把它清除。14.1.5 Probe Contact is Unreliable or Intermittent 探针接触不可靠或断断续续1. This could be caused by the board not pulling down far enough as described earlier in this chapter.可能原因：与这章前面说的一样，线路板没有下拉充分。 2. The probes might need to be cleaned or replaced.探针也许需要清洁或替换。3. There might be corrosion or flux on the circuit board.在线路板上也许有腐蚀或助焊剂。4. The probe head style might be incorrect for the type of contact encountered on the board. Use the following guidelines for determining which probe head style to use.针头类型也许与板上的接触点类型不一致。利用下面的指南决定使用哪种针头类型。Single Point - Used for penetrating moderate concentrations of surface contaminations such as oxides and flux. You can also use this head style for contacting eyelets, clean flat surfaces, and noble metal plated-through holes.单个针尖- 用于穿透表面污染的中等程度的集中，象氧化物和助焊剂。Spear Point - Used for penetrating heavy concentrations of surface contaminations. It can also be used to probe flat surfaces. These probes should not be used to probe unsoldered eyelets because sometimes an eyelet will “capture” the probe and pull it form its receptacle when vacuum is released.矛型尖端 - 用于穿透表面污染严重的板子。它也可以用来探测平的表面。这种探针不用于探测没有上锡的针眼，因为有时针眼会“抓住”探针，在真空释放的时候将把它拉离插座。Serrated Tip - Used for probing surfaces that are not flat; for example, short component leads, either straight or bent, such as those protruding from a solder fillet.锯齿状针尖 - 用于探测不平的表面，例如，短的元件引脚，或直或弯，比如焊接带的突出。Star Tip - Used for probing most component leads, either short or long. This head style is “self-cleaning” and does not require as much maintenance as the serrated tip probes. 星型针尖 - 用来探测大多数元件引脚，或长或短。这种针头类型是“自清洁”的，不需要象锯齿 针尖那样多的维护。5. The probe-to-circuit board registration might be inaccurate. This could be caused by not using entry material during the drilling process. If this is the cause, you will have to re-drill the plates. Poor registration can also be caused by bent or improper installation (non-vertical) of tooling pins. Either replace or straighten the tooling pins if this is the problem. Registration problems can usually be detected by placing the support plate on the fixture and sighting through the holes on the plate looking for misaligned probes. Ifas in the case of a cassette you do not have a support plate, you can use an unsoldered, blank circuit board as a registration guide. Another way to check probe alignment is to install all single point or spear point probes in the fixture. Then place a freshly soldered, blank circuit board on the fixture and activate the vacuum ( or the press, in the case of a cassette). Remove the board and examine the probe indentations in the solder under magnification.针到板的配合可能是错的。这有可能是由于在钻孔过程中没有使用进入材料。如果是这个原因，你要重新钻孔。不好的配合可能是由于弯曲的或不正确的加工针的安装。如果有问题，替换或弄直加工针。配合问题可以这样检测，将支撑板放到夹具上，通过支撑板上的孔找不重合的探针。假如，象一盒磁带一样，你没有一块支撑板，你可以使用一个没上锡的空白的线路板作为配合指导。检查探针排列的另外一个方法是，在夹具上安装所有的单针尖或矛尖的针。接着放一块刚上锡的，空白的线路板在夹具上，启动真空压力。拿下板，在放大情况下检查探针的缺口。14.1.6 The Fixture is Excessively Noisy夹具非常吵杂Some air-flow noise is normal. However, if the fixture is unacceptably noisy, one of the following four things could be at fault.一些空气流动的噪音是正常的。然而，如果夹具噪音不能接受，可能就是下面四个原因中的一个。1. The HP Spring Seal could be leaking. To determine if this is the problem, with vacuum applied, run your fingers along the perimeter of the support plate while listening for a change in the noise level or tone. Solve the problem by repositioning the seal, replacing the seal, replacing the Hi/Lo Tack adhesive, or sealing the corners of the seat as explained in chapter 8. HP Spring Seal正在泄露。为确定是否这个问题，施加真空，将你的手指沿着支撑板的周边移动，听噪声或声调的改变。要解决这个问题，重新放置密封条，替换密封条，替换Hi/Lo Tack粘合剂，或如第8章写的那样密封座垫的边角。2. The circuit board gasket could be defective or improperly installed. To check for this, press on the board after vacuum is applied. If the noise disappears or changes, the gasket might very well be at fault. Refer to chapter 8 for more information about gasketing. 整个线路板的衬垫可能有问题或被错误的安装。要检查它，在真空加上后检查板子。如果噪声消失或改变，衬垫就有故障。第8章有很多关于衬垫的信息。3. Air can also enter through unsoldered vias or holes in the circuit board. Place gasket material on the support plate beneath these holes or vias. For large numbers of unsoldered vias, you might want to construct a vacuum cover to seal the board.空气也能通过线路板上没有上锡的通孔或洞眼。将支撑板上的衬垫材料放在这些通孔或洞眼下。对大量的没有锡的通孔来说，你也许要做一个真空盖子来密封板子。4. If the fixture leaks between the gasket and the circuit board, this could be caused by a local area of dense probes near the edge of the board not allowing the board to pull down far enough onto the gasket material. This can usually be fixed with the addition of HP PrdLoaded springs near the high density area. 如果夹具在衬垫和板之间泄露，原因可能是在板的边缘的高密度的探针引起，它们阻止线路板下拉到衬垫材料上。这一般可以在高密度区域增加HP PrdLoaded 弹簧来解决。14.2 MAINTAINING YOUR FIXTURES维护你的夹具Regularly scheduled fixture maintenance is not noly recommended, but is required if you are to have an efficient board test operation. Gasket and probes wear out and can cause significant production delays if left to fail on their own. 有规律的，预先计划好的夹具维护不仅是个建议，如果你需要一个有效率的电路板测试操作平台，你就必须这样做。衬垫和探针会损耗，如果任它们这样下去，将导致重要的生产的延迟。 In fact, high volume board test process should consider building spare, fully functional, tested, support plates for their fixtures. A spare plate can be quickly swapped with a defective support plate, which eliminates significant fixture down time. 事实上，大量的电路板测试过程应考虑为夹具制作备用的，完整功能的，测试过的支撑板。一块备用板能快速与有问题的板交换，可以消除重要的夹具的停机问题。 The following paragraphs describe those things that can , and probably should, be checked in a periodic fixture maintenance program. Also included are some recommended maintenance methods and fixture storage considerations. The amount and frequency of scheduled maintenance depends on fixture usage and your departments maintenance philosophy, so these are not specified in this chapter. 接下来的段落讲述了一些在定期维护夹具过程中能够做的，应该做的一些事情。也包含了一些被推荐的维护办法和夹具保存的建议。定期维护的数量和频率要根据夹具的使用和你的部门的维护体系来定，所以在这章中没有提及。14.2.1 Maintaining Support Plates维护支撑板 Support plate assemblies require more maintenance than any other fixture element. The following items should routinely be inspected as a part of any fixture maintenance or repair procedure. 支撑板装配与其他的夹具部件相比需要更多的维护。接下来的项目将作为任何夹具维护的一部分或维修过程来检查。 Circuit Board Gasket - Check he gasket for wear, and adhesive integrity, and replace any questionable sections. 电路板衬垫-检查衬垫的磨损，胶粘的完整性，并替换任何有问题的部分。 HP DuraDam - Check for wear and adhesive integrity and replace any damaged pieces. HP DuraDam -检查衬垫的磨损，胶粘的完整性，并替换任何损坏的板片。 HP Spring Seal - Check the seal for adhesive integrity, especially the low-tack adhesive. You can replace the low-tack adhesive by removing the adhesive tape from the seal and replacing it with the Hi/Lo-Tack tape provided in the HP 44200K Spare Parts Kit.Check all splices and corner seals. Replace any damaged sections. HP 弹簧密封 - 检查密封的胶粘完整性，特别是low-tack adhesive.你可以拿掉密封上的胶带，用HP 44200K备件箱里的Hi/Lo-Tack 带替换low-tack胶带。 Spacers - Make sure that all the top- and bottom-side spacers are firmly attached to the support plate; replace any that are not, or have fallen off. 隔离片 - 确认所有的顶边和底边隔离片都牢固的粘贴在支撑板上，替换任何没有的或掉下来的隔离片。 To complete the maintenance, you should perform a vacuum seal check with the support plate on the probe plate. Make sure that the board pulls down evenly and completely without excessive air-flow noise or flexing of the circuit board. 要结束维护，你应该对在探针板上的支撑板进行一次真空密封检查。确保板放平了，而且完全没有多余的气流噪声或电路板的弯曲。14.2.2 Maintaining Probe Plates 维护探针板 Probe plate inspection should also be a part of any regularly scheduled maintenance program. Check for the following discrepancies. 探针板检察也应该是任何规律定时维护程序的一部分。检查下面的差异。 Probes - Check for bent or damaged probes. Ensure that all probes spring back when compressed. Sight across the top of the probes to see that all probes are seated properly in their receptacles (note that different probe types-50-mil, 100-mil, etc.are seated to different heights). Clean probes as necessary (see “Cleaning Probes” below). Replace any probes whose tips are black or have black spots on them. These black marks are indicative of the gold plating being worn through, which allows the base metal to oxidize. 探针 - 检查弯曲或损坏的探针。确保所有的探针在受压的时候能缩回去。从探针的顶部看所有的探针是否正确的安装在他们的插座上（注意不同类型的探针- 50-mil, 100-mil,等。- 都有不同的高度。有需要的话清洁探针（看下面的“清洁探针”）。当针尖是黑的时候或有黑色斑点在针上的时候，替换探针。这些黑色痕迹表示表示着镀金层磨损坏了，里面的金属会被氧化。 Receptacles - Check for receptacles that are not seated at the correct height. Receptacle set height depends on its usage-e.g., 50-mil, 100-mil, or dual-stage probes-and whether it is installed in the top or bottom probe plate. Receptacle set heights are earlier in this manual. 插座 - 检查那些不在正确高度安装的插座。插座高度依赖于它的使用- 例如，50-mil, 100-mil, 或双节探针-不管它是安装在探针板顶部还是底部。插座高度设置在这个指南之前。14.2.2.1 Cleaning Probes清洁探针Multi-point probes can collect foreign material such as dirt and flux; you should clean these probes periodically so that they continue to maintain good electrical contact with the circuit board being tested. 多头探针能聚集外来的物质，例如，灰尘和助焊剂；你应该定期清洁这些探针，以使它们与被测的电路板继续保持良好的电气接触。 Use a short-bristle, stiff, plastic or nylon brush to lightly brush the probe heads. Be careful not to brush the probes so vigorously that you bend them. Replace any probes that do not clean up with just a light brushing. 使用短毛的，硬的，塑料的或尼龙的刷子轻轻的刷探针头。不要很用力的刷探针，你会弄弯它们。如果轻刷不能清洁的探针，替换之。 CAUTION Do not use solvent to clean probe tips. The probe mechanism contains lubricant which can be diluted or washed away by solvent. Without this lubricant, probe life will be significantly reduced. 警告 不要使用溶剂清洁探针尖端。探针机构包含有润滑剂，而熔剂能冲淡或冲掉润滑剂。没有这个润滑剂，探针寿命将被严重的缩减。 As a result of wear between the probe barrel and plunger, black oxidized metal particles can accumulate. A certain amount of this residue is normal and by itself is not cause for replacing the probe. 由于探针圆筒和探针杆之间的磨损，黑色的氧化金属碎屑会聚集起来。一定数量的这种残渣是正常的，单凭这一点不是换针的理由。14.2.3 Maitaining Alignment Plates and Pin Blocks维护板队列和针块Alignment plates and pin-block assemblies normally need very little maintenance. Just inspect them for foreign material and bent pins, and then blow them off with non-oiled compressed air. 板队列和针块的集合一般需要很少的维护。只要察看是否有异物和弯曲的针，接着用不含有油的压缩空气吹掉它们。NOTEWe recommend that you do not routinely remove and replace the alignment plate for inspection or cleaning. This should only need to be done to replace a receptacle or a personality pin, or when rewiring for an engineering change. 注意我们建议你不用为了检查和清洁移开和替换板队列。这个只有在替换插座或personality pin时，或为了工程转换重新接线时才需要做。14.2.4 Rotating “KnownGood” Boards A known-good board is the circuit board that stays with the fixture and is used by the board test operator and developer to determine test system/program integrity. If the test program passes the known-good board, then the opera