标签: test

电视/显示屏幕、投影机与家庭影院音响三大类产品，是构建家用视听环境的主要元素。随着显示技术不断的提升，例如屏幕分辨率越来越高，消费者的焦点也从画面呈现的细致度转向到高水平的音质输出，以追求更好的影音体验。近年来影音规格趋于多元化，形成新的家庭影音生态链以及创新应用趋势，其中又以Dolby及DTS为环绕音效市场的主流。 以Dolby系统音效为例，喇叭声道数从最开始的Dolby Pro Logic 5.1声道，规格持续升级到最高规格的Dolby Atmos 24.1.10 声道。至于什么是Dolby Atmos呢? Dolby Atmos为杜比实验室于2012年4月首度发表的电影环绕音效技术，舍弃声道概念(replaced channel dependency)，将声音混合成音频元素 (audio element)组成一个声音对象(sound object)。因可以布置在3D空间中的任意一点，准确地规划声音来源及其移动的方向和位置，更能让环绕音效从平面进阶到立体环绕，使得视听体验更加逼真。另外，为了完整传递Atmos所带来听觉体验，杜比实验室推出了全新音频编码技术「Dolby ED2」，Dolby ED2是Dolby E的延伸技术，因此可以向下兼容；透过全新的后设数据系统(Professional Metadata, PMD)，Dolby ED2编码技术可以完整传递更有如临现场的听觉享受。 图1：家庭杜比全景声示意图 「 Dolby Atmos for Home 」杜比天空声道 到你家 2014年杜比实验室有了重大宣布，将原本只能在电影院才能享有的Dolby ATMOS技术，带入家庭影院系统，称为「Dolby Atmos for Home」 。家用的Atmos版本目前最多支持24个平面声道与10个天空声道(24.1.10)，可以同步处理多达128个声音对象(sound object)。在今年的WWDC 2018上也宣布最新版的tvOS将支持Dolby Atmos，此版本升级可以让家中的系统更加接近电影院的音效，更让消费者不必出门就能在家享受到这新一代的立体环绕音效，进一步提升家庭影院效果。 然而，在现实生活中，消费者真得能够根据产品规格、挑选出符合自身期待的影音设备吗?不知您是否有过这样经验，在参观影音设备专卖店时，不但听了店员详尽的解说也仔细看了产品规格，兴高采烈地买回家后，却发现喇叭声音不够大、高音不透彻、低音不够力，甚至调高音量却带来超震撼的破音效果？ 影音生态圈验证方案 尽在百佳泰 在音频量测上累积多年经验的百佳泰实验室，深知「音质」是影响用户观感的一大主因，特别是Dolby Atmos主打音质「细腻拟真」为特色，各声道只要出现任何一点异常状况，就会更加影响到观赏影片的兴致。以Dolby Atmos测试为例，在测试过程中我们发现，破音跟杂音是会偶尔发生的，不过也因为Dolby Atmos的声道数多，每个声道都各自负责不同声音表现，要怎么从众多的喇叭中评测出微小的声音异状也是一大课题。因此针对Dolby Atmos测试，我们备齐了市面上所有支持Dolby Atmos功能的影音相关设备，以确保设备的多样性及配置可以符合不同客户的产品规格以及测试需求。 ※关于支持Dolby Atmos功能之AVR可参考Dolby官方网站 https://www.dolby.com/us/en/categories/AVR.pdf 根据百佳泰测试团队的Issue Database的大数据分析，我们发现在家庭影音的兼容性测试中，外围设备在串接使用中所造成的问题，影像与声音的问题大约各占一半。 以下为我们从以往家庭影音测试案件中挑选出几种验证过程中的常见问题： 图2：家庭影音设备串接示意图 1. 声音输出不同步或声道输出不正常 当机顶盒在播放影片中的某特定片段时，发生背景声能够正常输出、人声却突然被消音；另外，影片播放时不同声道（如低重音、左右声道）所输出的声音不同步或不正常，亦或在特定操作如暂停快进、回放、系统休眠之后会发生爆音或无法输出声音的状况。意味着AMP/AVR在译码或系统状态切换时，与播放源头的影片发生了兼容性问题。 2. 影像、字幕或预览窗口无法显示 除了产品功能性测试，百佳泰也会模拟一般用户情境，执行情境测试，例如，透过遥控器模拟用户想要快速得知剧情发展的真实状况，在用户移动时间轴的当下，预览窗口快进至欲观看的片段，但测试团队发现时间轴上的预览窗口没有正常显示、呈现黑屏，或是特定设备连接后在操作时会有影像或字幕不正常显示的状况。 3. 关闭任一串接设备，影音无法跟着连动 将TV与AMP串接、进行影片播放时，您是否有发生过以下状况? 将电视关机之后再开机，却发现影片并没有继续播放，而是回到影片的开头重头播放 TV持续开机状态但关闭AMP后，TV喇叭输出的声音突然间变大声 TV串接soundbar时，TV遥控器还可以调整soundbar声音，然而换成串接AVR时，TV遥控器却无法控制AVR；反之若是先串接AVR、再换成soundbar， TV遥控器不但能控制AVR音量，也可控制soundbar，并没有问题发生 这些非预期效果，在经由我们测试之后，发现可能与影音频号的译码或HDMI CEC兼容性(注1)问题有关，由于不同厂牌影音设备之间多少都会遇到协议沟通上的差异，我们建议厂商在出货前能够进行兼容性测试，以避免造成用户体验不佳等情况发生。 注1：所谓的HDMI CEC（Consumer Electronics Control）兼容性功能，为HDMI传输的规范之一，指的是可以让不同品牌及器材之间的遥控器互通，例如A牌的TV与B牌AMP串接时可以用A牌的TV遥控器控制B牌AMP。 总结 目前家庭影音产品有别于过往并从单一功能逐渐向多功能发展，针对现代家庭拥有多样化娱乐视听设备的趋势，例如Dolby及DTS环绕音效系统，消费者除了对音效质量有日益渐高的要求外，各影音规格是否具备在影音装置有效运作的能力，这将会是接口设备厂商重要课题之一。上述发生的常见问题其背后原因各有不同，有些是AVR音效译码问题，有些则是HDMI CEC兼容性问题等；这些潜在的问题风险，都需要靠多样化的测试情境设计并经过反复验证，才能找出问题所在，进而改善并提升质量。 随着影音设备系统新功能与新应用的开发，拥有全球最齐全影音设备数据库的百佳泰实验室，已随时准备提出在地化的影音客制化测试服务，协助客户找出所有潜在风险危机，以符合厂商在不同市场的测试验证需求。

Picking up where I left off in these test capacity management chronicles, I am reminded of a season of significant growth in semiconductor test outsourcing followed by a tightening of test capacity management strategies after the dot-com bubble had burst. Still at Teradyne during that time, I primarily worked with both Freescale, Qualcomm and their many outsourced semiconductor assembly and test (OSAT) partners.   In the late 1990s, Freescale launched its "asset light" strategy to rein in what had become a large and unwieldy global manufacturing operation fraught with underutilized assets. The new strategy was designed to optimize the balance of internal manufacturing and outsourced manufacturing, leveraging the then very capable and reliable foundry and OSAT ecosystem. The leading foundries such as TSMC had already proven they could achieve profitable economies of scale by aggregating the front-end fabrication requirements of multiple customers, and the OSAT providers were striving to prove the same for backend assembly and test.   There is, however, a fundamental difference in how test capacity is established -- relative to fabrication capacity and assembly or packaging capacity -- that impacts the aggregation efficiencies and economies of scale of the test provider.   For fabrication and packaging, the equipment configurations and available process steps are generally predefined, and users must adhere to published design rules to use the manufacturing capacity. This model creates relatively uniform and predictable capacity. In contrast, for test, the user (e.g., the chip designer) determines the processing "rules" by specifying the configuration and cycle time of the equipment and the process required for testing a specific chip. The test capacity user can therefore be referred to as the test specifier.   Test capacity is "specified" by the chip designer, unlike other capacity in the semiconductor manufacturing process.   With test specifier "rules" often unique for each of the thousands of chip types being tested every day, test capacity is essentially variable and more difficult to manage and keep utilized. The requisite economies-of-scale returns for a profitable outsourcing model are therefore not as readily realized by the test provider as they are for the foundry. These challenges still hold true today.   Still, Freescale eventually trimmed its internal backend capabilities from seven to two facilities, and the OSATs continued to grow. As the new millennium approached, the dot-com bubble caused the growth in semiconductors and everything high tech to soar. Test capacity utilization was therefore at a peak, and the biggest concern related to test capacity management was simply capacity availability. The end of the dot-com era brought test capacity utilization lows -- and an entirely different view of test capacity management -- to the OSATs and other test providers. I'll discuss my introduction to Qualcomm and explore the dot-com impact on test capacity management in my next entry.   Dan Hamling is CTO at Team A.T.E.

Anyone here who still remembers the Heathkit "Stackables"? These were presented with a blue plastic box and a white front panel in build-it-yourself kit form.   As I recall, the Ix-528x series included a multimeter, RF signal generator, audio signal generator, signal tracer, RLC bridge, and -- possibly (I can't remember for sure) -- a power supply. These were a family of low-cost basic test instruments for the electronics experimenter/hobbyist/repair person. Their notable claim to fame was that they were all built into the same plastic cabinet that featured molded feet that interlocked with a molded top ridge so they could be stacked vertically and stably on a benchtop, thus saving a lot of scarce and valuable real-estate.   Think for just a moment about this simple concept, and how it can similarly apply in your food pantry. Lately I've noticed two types of tin cans -- the older style that can be vertically stacked because their bottoms mate with the tops of the cans beneath them (e.g., Campbell's soup tins), and a newer style that was designed by some dimwit who did not think to include the stackability feature (e.g., Kroger-brand veggies). Try to stack these types and they come crashing down like a house of cards. No question as to the preferred type to make the best use of the limited horizontal space in a pantry.   Other than the intentional Heathkit stackable feature, most older styles of test equipment were not designed to be stackable. However, since they typically came in flat-topped cabinet enclosures, this was an inherent attribute. Even units from different manufactures could easily be stacked on a bench into a reasonably stable "tower of power" -- just look at any of illustrator Daniel Guidera's monthly EETimes caption contest cartoons for examples.   Then, along came the aesthetic enclosure designers hired by marketeering managers with no brains. Fancy curves and non-flat tops -- test equipment styling started looking more like sports cars than truly functional items. The result is that many of them can no longer be stacked.   Keeping this in mind, let's look at how some of these non-mating test equipment boxes can be made to fit together on a limited-space benchtop. Consider the DMM sitting on top of a power supply as shown below. The unfolded front tilt-flap of the DMM keeps it from sliding backwards off the tilted-upwards power supply, but it tends to slip forward and hide the power supply's display.     However, when the tilt-flap folded against the DMM bottom as shown below, it prevents the DMM feet from engaging the power supply and it slides off.     One solution is to forcibly remove the annoying tilt-flap from the DMM, thereby allowing its feet to hold it somewhat in place. But the serial number that is on the tilt-flap is no longer part of the DMM, which could raise some issues with the ISO-9000 calibration auditor.   Next, consider the frequency counter sitting on top of a function generator as shown below. The front lip of the frequency counter holds it from slipping off the function generator, but it does make the function generator's button labels hard to see.     Swapping these two devices round and placing the function generator on top of the frequency counter doesn't work; the function generator's tilt-riser holds it from slipping off, but hides the counter's digits.   Even identical equipment made by the same dimwit manufacturer who never considered stackability can be stacked with the aid of series-connected cable tie-wraps as shown below (don't use duct tape because it can cover up the ventilation holes). By the way, if you have to tie-wrap-stack two scopes together to make a 4-channel scope, you (or your corporate fiscal expenditure manager) might be a Redneck (with apologies to Jeff Foxworthy).     Note that these Atten brand "Scopes from Hell" have a couple of functional bugs (among many) that are clearly visible in the above photo. One of these bugs is fairly obvious -- the other is a little more hidden. Can you spot these bugs? If so, please post a comment below. Also, please offer any suggestions you have for stacking these types of devices on your benchtop.   Glen Chenier Engineer

In Part 1 , I left off by discussing the industry shift to proactively managing tester configurations. I'm sure my story triggered memories of a similar season at your company when a more global assessment of your test configurations and capacity became essential to your survival. If so, how did you first start tracking your configurations back then? Maybe your experience and tool set was like mine described below.   Much like the case today, the test systems in the mid-1990s produced an electronic configuration file or "config file" that contained a rich set of detail on the hardware options in the system. The problem was that config files were readable by only a select few in the test community.   As a Field Product Specialist at Teradyne, I was trained to be one of those few. I spent a great deal of time manually checking and translating those files to not only ensure accurate alignment to system orders and device requirements, but to create readable summaries for sales, purchasing, and management. I also had to make sure important information not included in the config file made it into the orders, summaries, and the like. This work was performed using a variety of familiar formats like text files, spreadsheets, and presentation slides, but many of the details in the original config file were inevitably lost in translation.   While many loathed the config file, I embraced it. I considered it part of what allowed me to have "Specialist" in my title. More importantly, working with config files always provided an opportunity for geek humor by making the proverbial, but likely overused, "secret decoder ring" reference ( figure ). I just did it again.   Config files, often written with text editors or spreadsheets, contain information on how ATE systems will be set up for a particular test.   Not everything was, however, done in a text editor. The most innovative related endeavor at the time was the internal development of a customer tester configuration manager in HTML, to be viewed on what was then a nascent Netscape browser. A clever solution for sure, but one that drove perhaps five page views per month, and really had just two unique visitors: I was one, with the other another test engineer in the office with a similar thing for configurations.   When I look back on those times, I don't really see much that has changed in the area of test capacity management tools and methodologies. The system config files are still esoteric and are complicated even further by the addition of floating feature licensing schemes. The tools used to document tester configurations have changed versions but are also largely the same. Unfortunately, there remains a loss of information and efficiency in the translation and communication process. Perhaps now is the time to bring back that web-based configuration manager!   Dan Hamling is CTO at Team A.T.E.

I recently underscored the major stakeholder groups in the test industry that care about test capacity and how it's managed: the test specifier, test provider, test equipment manufacturer, and third-party supplier. Over my long career in the test industry, I've been fortunate to have had the opportunity to think about test capacity and its management challenges from the perspective of each of these groups.   Although I saw significant and exciting innovation in ATE and test techniques over those 27 years, I saw relatively limited development of test capacity management tools and methodologies. My next few posts will provide a chronological review of some of my test capacity management experiences to see if you agree.   My early years as a test engineer at Hewlett-Packard had no test capacity management challenges. As part of a low-volume custom bipolar ASIC design center, we did all our test engineering and production on just one Sentry Series 80 tester. We were essentially both the test specifier and test provider in this case, but with access to only a single fixed unit of test capacity. Our challenge then had more to do with testing a 2 GHz bandwidth, 500 Msps oscilloscope front-end sampling device on a 20 MHz tester. (Answer: rack-n-stack like crazy and develop 3 GHz probecard technology).     When you have more than one ATE station, test management becomes important.   When I joined Teradyne and relocated to Austin, Texas in 1995 to primarily work with Freescale (then Motorola's Semiconductor Products Sector), I saw for the first time the world of large device portfolios and high-volume manufacturing. Along with that world came test capacity management challenges I hadn't experienced before. As Freescale built up its installed base of A5-Series testers and transitioned to the new Catalyst platform for their analog and mixed-signal products, we spent a significant amount of time together planning and managing the ATE configurations that would be used worldwide by this multi-national company.   Proactively developing a set of ATE configurations that aligned with the long-term device roadmap is common test capacity management practice now, but was actually not as prevalent for earlier generations of ATE. The proud owner of hundreds of tester platforms at the time, Freescale, like other large semiconductor companies, got to that point by allowing its various product groups to independently specify ATE based largely on just the technical requirements of their new device or, at best, family of devices. And, test equipment manufacturers such as Teradyne happily provided specific solutions for each device.   This strategy was eventually disrupted by the realization that test capacity utilization was an important cost-of-test lever that must be managed more closely to effectively compete in the growing global semiconductor industry. Coupled with this trend was the advent of architectural innovations in ATE that allowed for a much wider range of configuration options and thus demanded a more careful configuration assessment and plan.   So, what compelled you to first start prioritizing and performing long-term ATE configuration planning? When did it happen for you? In Part 2, I'll continue my discussion of this first major movement in test capacity management, focusing on the tools and methods we used to perform this work.   Dan Hamling is CTO at Team A.T.E.