Prática de Shadowing: PCBs | Electronic Goods Reliability Testing - Aprenda a falar inglês com vídeo

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Welcome to this next video in the series for PCBs.
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Here we're going to be looking at electronic goods and the reliability testing.
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Let's start with reliability and durability.
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New product development is a complex process and takes time and a key step in the processes
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testing your product for reliability and durability.
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The main reason for reliability testing is to find out what the performance is over a long period of time.
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Reliability test results may be categorized using the bathtub curve shown on the right here.
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The bathtub curve shows the decreasing failure rate during the early infant mortality days of the product,
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leading to the normal life of product population and finally the onset of the end-of-life wear out.
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You can see here the decreasing failure rate section, the constant failure rate and the increasing failure rate.
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The blue curve is the bathtub shape.
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Let's switch over to temperature and humidity.
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Temperature and humidity testing determines
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how a system behaves in extreme conditions where the product is operated in high and low temperatures
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as well as cycling the temperature between high and low.
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Among other things, temperature
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and humidity test studies the effects of climate changes on electronic components such as failures due to parameter shifts,
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mechanical failures due to rapid water or frost formation, optical failures as in fogging,
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water tightness in packaging and looking at the failures,
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and material degradation or epoxy coatings etc and much more.
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The table on the right here shows an example of shipping
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environmental tests where it goes from step one to five and the humidity and temperature starts at low,
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raising to high and then back down to low again.
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On the right hand side it shows the duration for each of these tests.
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RH just stands for relative humidity.
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Vibration testing.
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The applications of vibration testing form a major part of quality assurance for everything from printed circuit boards to completed products.
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With specifically designed equipment such as mechanical,
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electro-hydraulic and electromagnetic shakers, test samples are typically subjected to varying degrees of controlled vibration stresses.
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Products are vibration tested to determine limits and tolerances.
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Every product is vulnerable to vibration loads and potential breakage or failure.
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You can see here, typical vibration test machine.
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Mechanical shock testing.
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The ability to withstand mechanical shock is both a key design consideration
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and an important selling point for certain types of consumer goods.
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For this reason, a dynamic mechanical analysis is a required component of quality control and product testing.
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A shock test will measure the impact of sudden acceleration or de-acceleration using precise tools such as strain gauges,
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load cells, and piezo sensors.
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Here we can see a mechanical shock testing equipment and the setup.
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Now I want to talk about the highly exaggerated life test or the HALT process.
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HALT is applied to the initial product testing stages prior to production
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and its primary objective is to highlight failure modes
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and weaknesses in the design so the design can be modified and improved to eliminate any weaknesses found.
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In HALT, temperature and vibration stress conditions
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are used during product development to find weak spots in the product design and its planned fabrication processes.
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Other test stimuli may include humidity, thermal cycling, burn-in for a specified period of time,
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overvoltage, voltage cycling and anything else that could logically expose defects.
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This test requires only a few units and a short testing period to identify the fundamental limits of the technology being used.
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Generally every weak point must be identified and fixed or redesigned if it does not meet the product's specified limits.
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This is a typical flow process for the whole process.
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We can see at the top here we've got start we
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then drop down into the first test cycle here we're looking at temperature operation limits with voltage limits.
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We can see then if we've got the decision point, failure occurs or not.
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If it does not occur, then it just drops into the next test cycle.
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And here we've got the thermal cycle.
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And again, the decision point there, if it does not fail, it completes the cycle with a vibration test.
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If however, at any point during these tests,
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the failure does occur, then you can see it drops down to the bottom, leading the requirement to analyze what that root cause was,
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then moving into manufacturing process improvements, improvements from the design features,
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improved component choice etc and then coming back through that complete cycle until everything has passed this process.
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Next let's have a look at the highly accelerated stress screening or HAS.
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HAS is implemented at the production stage where the production samples
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are subjected to stress testing beyond the product specification limits but not up to the extreme levels used in the HALT test.
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The objective of HAS is to ensure products from production meet the life expectancy without showing any signs of failure modes.
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Early production failures on a new product are often attributed to
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variability within the manufacturing process therefore identifying these potential production failure
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modes as early as possible is paramount to the success of a product launch and this is where has comes into play.
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A random set of production items will be selected for the production line
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and then placed under different stress tests that can highlight production faults
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that are not only obvious but will also identify any of the latent faults that are not detectable in normal production testing.
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This reliability screening allows potential faults to be identified that are normally associated with early production failure in the field.
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This provides the engineering team to work on corrective actions
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and process improvements thus creating a more robust and reliable product that would otherwise lead to potential product failures for the customer.
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In summary, this process is ideally suited to all electronic
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and electromechanical assemblies so that a more reliable and robust product can be released into the marketplace.
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Let's have a look at a quick graph for HAS.
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On the extreme ends of the graph we have the lower and upper destruction limits.
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The next set of limits in are the lower operational and the upper operational limits.
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In the center here we have the has section and the production specification limits.
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We can see that the manufacturing defects removed by the has testing highlighted in red.
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This is the objective of the has testing to remove these poor products.
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Let's have a look at the HALT and the has summary with a timeline.
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We can see in In the table, across the top we have the typical test profile for both HALT and HALT,
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the defects being addressed, development phase being applied and the stress levels.
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From a timing point of view across the bottom, the HALT test is clearly shown in the design phase,
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whereas the HALT test is highlighted at the end of the manufacturing phase.
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The importance of product reliability.
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You never get a second chance to make a first impression.
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So making sure your products are reliable before you bring them to market can prevent problems that can doom your business.
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Understanding some of the basic benefits of reliability testing will help
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you make sure you're ready to sell with minimal problems from day one.
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Making sure your product is reliable can also help you spot design
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and production flaws that can cause failure and potential injuries to users.
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Just one successful lawsuit can put you out of business.
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Remember, put reliability first.
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Don't forget to check out our other videos in this series
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and you can contact us if you need any help with your projects at all in China.
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Don't forget to like, share and subscribe to our channel.
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For more information you can always visit our website and go to the solutions page.
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Thanks for listening, my name is Paul Adams from South East and I shall see you in the next video.

Sobre esta lição

Nesta lição, você vai praticar o inglês técnico sobre testes de confiabilidade de componentes eletrônicos, como PCBs. Através do vídeo, você aprenderá a falar sobre processos de teste, termos específicos de engenharia e estruturas de frases usadas em contextos profissionais. O foco é melhorar a compreensão auditiva e a pronúncia, usando técnicas de shadowing para se adaptar ao ritmo e ao tom do diálogo.

Palavras-chave e frases úteis

  • Reliability testing (Teste de confiabilidade): Processo para avaliar o desempenho de um produto ao longo do tempo.
  • Bathtub curve (Curva de banheira): Gráfico que mostra a taxa de falhas de um produto ao longo de sua vida útil.
  • Vibration testing (Teste de vibração): Método para verificar a resistência de componentes a movimentos oscilatórios.
  • HALT (Teste de vida exagerada): Processo de teste de design para identificar falhas antes da produção.
  • Thermal cycling (Ciclo térmico): Teste que varia a temperatura para avaliar a resistência de materiais.

Dicas de prática

Para dominar o conteúdo do vídeo, use a técnica de shadow speak: reproduza pequenos trechos (5-10 segundos) e repita imediatamente após o falante, imitando a pronúncia, o ritmo e a entonação. O vídeo tem um tom claro e um ritmo médio, ideal para iniciantes e intermediários. Aproveite para pausar e repetir trechos com termos técnicos, como "bathtub curve" ou "mechanical shock testing", até que a pronúncia fique natural.

Um shadowing site pode ajudar a organizar seus treinos, mas mesmo sem ferramentas, basta usar o vídeo e um notebook para anotar os termos difíceis. Lembre-se: a prática diária de 15 minutos é mais eficaz do que sessões longas esporádicas. Ao aprender inglês com vídeos, você não só melhora o speaking, mas também absorve contexto cultural e técnico, essencial para profissionais da área.

Teste-se: após 3 dias de prática, grave sua voz repetindo um trecho e compare com o original. Você notará uma melhora na fluência e na confiança ao usar termos como "HALT" ou "vibration testing" em frases completas.

O que é a Técnica de Shadowing?

Shadowing é uma técnica de aprendizado de idiomas com base científica, originalmente desenvolvida para o treinamento de intérpretes profissionais. O método é simples, mas poderoso: você ouve áudio em inglês nativo e repete imediatamente em voz alta — como uma sombra seguindo o falante com 1-2 segundos de atraso. Pesquisas mostram melhora significativa na precisão da pronúncia, entonação, ritmo, sons conectados, compreensão auditiva e fluência na fala.

Técnica de shadowing: leia o guia completo passo a passo →