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Constant Temperature And Humidity Test Chamber

Constant Temperature And Humidity Test Chamber

  • Double 85 Constant Temperature And Humidity Reliability Environmental Test (THB) Double 85 Constant Temperature And Humidity Reliability Environmental Test (THB)
    Jan 07, 2024
    Double 85 Constant Temperature And Humidity Reliability Environmental Test (THB) First, high temperature and humidity test WHTOL (Wet High Temperature Operating Life) is a common environmental stress acceleration test, usually 85℃ and 85% relative humidity, which is generally carried out in accordance with the standard IEC 60068-2-67-2019. The test conditions are shown in the chart. Second, the test principle "Double 85 test" is one of the reliability environmental tests, mainly used for constant temperature and humidity box, that is, the temperature of the box is set to 85℃, the relative humidity is set to 85%RH conditions, to accelerate the aging of the test product. Although the test process is simple, the test is an important method to evaluate many characteristics of the test product, so it has become an indispensable reliability environmental test condition in various industries. After aging the product under the condition of 85℃/85%RH, compare the performance changes of the product before and after aging, such as the photoelectric performance parameters of the lamp, the mechanical properties of the material, yellow index, etc., the smaller the difference, the better, so as to test the heat and moisture resistance of the product. The product may have thermal failure when working in a continuous high temperature environment, and some moisture sensitive devices will fail in a high humidity environment. The dual 85 test can test the thermal stress generated by the product under high humidity and its ability to resist long-term moisture penetration. For example, the frequent failure of various products in the humid weather period in the south is mainly due to the poor temperature and humidity resistance of the products. 3. Experimental factors In the LED lighting industry, many manufacturers have used the double 85 test results as an important means to judge the quality of lamps. Various possible reasons why LED lamps fail the dual 85 test are: 1. Lamp power supply: poor heat resistance of shell, danger of short circuit in circuit, failure of protection mechanism, etc. 2. Lamp structure: unreasonable design of heat dissipation body, installation problems, materials are not resistant to high temperature. 3. Lamp light source: poor moisture resistance, packaging adhesive aging, high temperature resistance. If you encounter a special use environment, such as the working environment temperature is severe, you need to test its high and low temperature resistance, the test method can refer to the high and low temperature test project. 4. Serve customers 01. Customer group LED lighting factory, LED power plant, LED packaging factory 02. Means of detection Constant temperature and humidity test chamber 03. Reference standards Constant temperature and humidity tests for electrical and electronic products -- Environmental testing -- Part 2: Test methods -- Test Cab: Constant temperature and humidity test GB/T 2423.3-2006. 04. Service content 4.1 Refer to the standard, conduct double 85 test on the product, and provide the third party's test results report. 4.2 Provide the analysis and improvement plan of the product through the double 85 test.
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  • Reliability Test Reliability Test
    Jan 07, 2024
    Reliability Test AEC-Q102 Test Certification Fixed Damp Heat with Humidity Cycling (FMG), LED lamp reliability test method (GB/T 33721-2017), Component screening Ammonia test CAF test, Flame retardant grade Cyclic corrosion test (CCT), Mechanical shock test, High pressure cooker test (PCT), Highly Accelerated Stress Testing (HAST), High and low temperature and humidity test (THB), Hydrogen sulfide test (H2S), Liquid tank thermal shock test (TMSK), Component humidity sensitive grade test (MSL), Screening for high reliability use Hot flash test + acoustic sweep screening for high reliability use (MSL+SAT), LED luminaires reliability test scheme, Vibration test (VVF), Temperature cycle/thermal shock test (TC/TS), LED red Ink test UV aging test, LED light source anti-vulcanization test, Double 85 constant temperature and humidity reliability environmental test (THB), Salt spray test check.
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  • Electric Vehicle Component Reliability Test Solution Electric Vehicle Component Reliability Test Solution
    Mar 08, 2024
    Electric Vehicle Component Reliability Test Solution In the trend of global warming and gradual consumption of resources, automotive gasoline is also sharply reduced, electric vehicles are driven by electric energy, reducing the heat of internal combustion engine, carbon dioxide and exhaust gas emissions, for energy saving and carbon reduction and improve the greenhouse effect plays a huge role, electric vehicles are the future trend of road transportation; In recent years, the world's advanced countries actively develop electric vehicles, for thousands of components composed of complex products, its reliability is particularly important, a variety of harsh environments are testing the electronic system of electric vehicles [battery cell, battery system, battery module, electric vehicle motor, electric vehicle controller, battery module and charger...], Hongzhan Technology for you to sort out electric vehicle related parts reliability test solutions, hope to be able to provide customers with reference. First, different environmental conditions will have different effects on parts and cause them to fail, so the parts of the car need to be tested according to the relevant specifications to meet international requirements and meet the foreign market, the following is the correlation between different environmental conditions and product failure: A. High temperature will make the product aging, gasification, cracking, softening, melting, expansion and evaporation, resulting in poor insulation, mechanical failure, mechanical stress increase; Low temperature will make the product embrittlement, icing, shrinkage and solidification, mechanical strength reduction, resulting in poor insulation, cracking mechanical failure, sealing failure; B. High relative humidity will make the product poor insulation, cracking mechanical failure, sealing failure and resulting in poor insulation; Low relative humidity will dehydrate, embrittlement, reduce mechanical strength and lead to cracking and mechanical failure; C. Low air pressure will cause product expansion, electrical insulation deterioration of the air to produce corona and ozone, low cooling effect and lead to mechanical failure, sealing failure, overheating; D. Corrosive air will cause product corrosion, electrolysis, surface degradation, increased conductivity, increased contact resistance, resulting in increased wear electrical failure, mechanical failure; E. Rapid temperature changes will cause local overheating of the product, resulting in cracking deformation and mechanical failure; F. Accelerated vibration damage or impact will cause the mechanical stress fatigue resonance of the product and lead to an increase in structural damage. Therefore, products need to pass the following climatic tests to test the reliability of components: Dust (dust) test, high temperature test, temperature and humidity storage test, salt/dry/warm recovery test, temperature and humidity cycle test, immersion/seepage test, salt spray test, low temperature test, thermal shock test, hot air aging test, weather and light resistance test, gas corrosion test, fire resistance test, mud and water test, dew condensation test, high variable temperature cycle test, Rain (waterproof) test, etc. The following are the test conditions for automotive electronics: A. IC and interior lights for locomotives, Recommended model: vibration of the comprehensive chamber B. Instrument panel, motor controller, Bluetooth headset, tire pressure sensor, GPS satellite positioning system, instrument backlight, interior light, exterior light, automotive lithium battery, pressure sensor, motor and controller, automotive DVR, cable, synthetic resin Recommended model: constant temperature and humidity test chamber C. 8.4 "LCD screen for cars Recommended model: thermal stress recombination machine Second, automotive electronic parts are divided into three categories, including IC, discrete semiconductor, passive components three categories, in order to ensure that these automotive electronic components meet the highest standards of automotive safety. The Automotive Electronics Council(AEC) is a set of standards AEC-Q100 designed for active parts (microcontrollers and integrated circuits...)and AEC-Q200 designed for passive components, which specifies the product quality and reliability that must be achieved for passive parts. AEC-Q100 is the vehicle reliability test standard formulated by the AEC organization, which is an important entry for 3C and IC manufacturers into the international auto factory module, and also an important technology to improve the reliability quality of Taiwan IC. In addition, the international auto factory has passed the safety standard (ISO-26262). AEC-Q100 is the basic requirement to pass this standard. 1. List of automotive electronic parts for A.EC-Q100: Automotive disposable memory, Power Supply step-down regulator, Automotive photocoupler, three-axis accelerometer sensor, video jiema device, rectifier, ambient light sensor, non-volatile ferroelectric memory, power management IC, embedded flash memory, DC/DC regulator, Vehicle gauge network communication device, LCD driver IC, Single power Supply differential Amplifier, Capacitive proximity switch Off, high brightness LED driver, Asynchronous switcher, 600V IC, GPS IC, ADAS Driver Assistance System Chip, GNSS Receiver, GNSS front-end amplifier...  B. Temperature and humidity test conditions: temperature cycle, power temperature cycle, high temperature storage life, high temperature working life, early life failure rate; 2. List of automotive electronic parts for A.AC-Q200: automotive grade electronic components (compliant with AEC-Q200), commercial electronic components, power transmission components, control components, comfort components, communication components, audio components. B. Test conditions: high temperature storage, high temperature working life, temperature cycle, temperature shock, humidity resistance.
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  • Smart Watch Reliability Test Conditions Smart Watch Reliability Test Conditions
    Mar 12, 2024
    Smart Watch Reliability Test Conditions In today's society, elementary school students and even kindergarten children have a smart watch. So, what is a smartwatch? In the late period of sports watch promotion due to the rapid takeoff of smart phones, the smart table has no intention to provide the same PIM effect as PDA and smart phones, and appeals to the smart phone agent assistant accessories, similar to Bluetooth headphones are voice AIDS of smart phones, smart tables become information and data AIDS, providing more convenient and fast information display and operation. There are also other names such as Smart Accessory and Android Remote. Positioned as a mobile phone assistant, the idea is that "the reason why the pocket watch is extinct is because it is simply to look at the time, but also take out the pocket, about 2-3 seconds, but the watch is less than 1 second, which is more convenient than the pocket watch." And after observation, now everyone takes out a smartphone and slides open, just to confirm the message, so that about dozens of times, these confirmation even typing reply do not need, if the dozens of confirmation changed on the watch, you do not always have to pull the machine slide unlock, because this is as time-consuming as a pocket watch. Therefore, after becoming the assistant of the mobile phone, the remote control, if you do not take the mobile phone to go out, the watch is useless in addition to showing the time, and the Bluetooth headset without a mobile phone, almost scrap metal. Combined with smart bracelet to sell better!! Smart watch from "smaller than the PDA independent computer" to "smart phone remote control AIDS", seems to have been a more successful positioning, but this CES 2014 can be seen, combined with smart bracelet positioning is better. The smart wristband uses acceleration sensors (and gyroscopes, magnetoresistive sensors, etc.) to sense the user's running speed, step count, etc., and can even detect deep sleep and provide suggestions for exercise and sleep. When the wristband is added to the display, it can display the time and information on the mobile phone. Appeal to mobile phone information, if there is no urgent information needs, in fact, only similar to the Bluetooth headset is regarded as an option (Courier, driver need), if everyone can accept the information access speed of sliding, then the market will be limited. However, in addition to the appeal for exercise and sleep record supervision, and emphasize information tips, rather than emphasizing the remote control of the watch on the mobile phone, it is equivalent to a little sacrifice or almost no sacrifice to the end user, but it brings immediate and new application value (sports, sleep assistance), rather than completely repeating the efficacy value of the mobile phone, which further increases the market success of the smart watch. After constantly adjusting the efficacy, application and positioning, and integrating with the smart ring, we believe that we can have a higher market than in the past.   Smart watch for people and functions: 1. Smart watches for adults Functions: Bluetooth synchronous mobile phone calls, send and receive text messages, monitor sleep, monitor heart rate, sedentary reminder, running, remote photography, music playback, video, compass and other functions, designed for fashion trend people! 2, Smart watch for the elderly Functions: ultra-accurate GPS positioning, family calls, emergency calls, heart rate monitoring, sedentary reminders, medicine reminders and other customized functions for the elderly, providing an umbrella for the elderly's travel, bring this watch, refuse to lose the elderly! 3, Children positioning smart watch Functions: multiple positioning, two-way call, SOS SOS, remote monitoring, intelligent anti-loss, historical track, electronic fence, pedometer, love reward and other functions, to ensure the safety of children, give children a healthy and safe growth environment!   Smart watch specification: IEC 60086-3: Watch batteries ISO 105-A02: Colour fastness test -A02 - Grey scale assessment for discoloration ISO 105-A03-1993: Tests for colour fastness -A03- Grey scale assessment of dyeing ISO 764: Horological anti-magnetic watches ISO 1413: Horological shockproof watches ISO 2281: Horological waterproof watches ISO 11641-1993: Leather - tests for colour fastness - Colour fastness to perspiration ISO 14368-3: Impact resistance test of table glass MIL 810G: Environmental engineering considerations and laboratory testing QB/T 1897-1993: Waterproof watch inspection QB/T 1898-1993: Inspection of shockproof watches QB/T 1908-1993: Key reliability test QB/T 1919-2012: Type inspection of digital quartz watches with hands and liquid crystal QB/T 2047-2007: Inspection of metal watchbands GB/T 2537-2001: leather color fastness test reciprocating grinding color fastness QB/T 2540-2002: Leather strap inspection GB/T 6048-1985: digital quartz electronic watch GB/T 18761-2007: electronic digital display indicator GB/T 18828-2002: Standard for diving watches GB/T 22778-2008: LCD digital quartz stopwatch type inspection GB/T 22780-2008: Type inspection of LCD quartz watches GB/T 26716-2011 idt ISO 764-2002: Inspection of anti-magnetic watches HJ216-2005: Eco-Drive watch   Smart watch pilot project: Reliability, time period measurement accuracy, instantaneous daily difference, operating temperature, voltage range, average temperature coefficient, voltage coefficient, moisture resistance, shock resistance, waterproof performance, battery replacement cycle, key fatigue resistance, light and weather resistance, antistatic performance Ambient temperature range: -25℃ ~ 55℃ Operating temperature: -5 ~ 50℃/80%R.H.(Requirements: each function and liquid crystal display should be complete and normal) High and low working temperature test: 50±1℃/24h→RT/1h→-5±1℃ Temperature change test conditions: (IEC60068-2) High temperature: 30, 40, 55℃ Low temperature: 5, -5, -10, -25℃ Nb residence time (including rising and cooling time) : 10min, 30min, 1hr Nb temperature variability: 3±0.6℃/min, 5±1℃/min.   Wet heat test: 1.40±1℃/85 ~ 95%R.H./24h 2.8±1℃/85 ~ 95%R.H./4h   Warehouse storage humidity test: 40℃/20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% 49℃/10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% Each step37 hours   Air transport temperature change simulation test: Specification: IEC60721.2 Electrical and electronic products application environmental conditions - transport national standard Category: 2K5 (Applicable to the climatic range of unventilated and unpressurized internal transport worldwide) Temperature range: -65℃←→85℃ RAMP: 5℃/min   Air transport temperature change simulation test: Specification: IEC60721.6 Electrical and electronic products application environmental conditions - Marine Category: 6K5 (subject to cold weather, installed in weather-protected but unheated parts) Temperature range: -25℃←→40℃ RAMP: 3℃/min   Water temperature change resistance test: 5min in 40℃ water → 5min in 20℃ water, 5min in 40℃ water, water depth of 10cm   Water pressure resistance test: Soak the watch in a container of water, apply an overpressure of 2*10^5Pa[or 20m water depth] within 1 minute, maintain 10 minutes, and then in 1 minute the pressure will be to the standard pressure of the surrounding environment   Salt water resistance test: Put the watch under test into 30g/L sodium chloride solution at 18 ° C ~ 25 ° C for 24h. Check the case and accessories after the test should not have significant changes; Check the moving parts, especially the rotating front ring should be able to maintain normal function   Underwater reliability test: The watch under test is immersed in 30cm±2cm of water and placed at a temperature of 18 ° C ~ 25 ° C for 50h, and all mechanical devices should still work normally. During the test, mechanical devices that need to be operated in water, such as time presetting devices and light switches, should be able to work normally; Do condensation test, the inner surface of the table glass shall not appear condensation fog, and the mechanical function should not be damaged   Thermal shock resistance test: Immerse the watch in water of different temperatures with a depth of 30cm±2cm successively: place it in water of 40 ° C ±2 ° C for 10 minutes; Put in 5℃±2℃ water for 10 minutes; Put in water at 40 ° C ± 2 ° C for 10 minutes (the watch shall not be removed from the water and re-immersed in another water temperature for more than 1 minute). Do condensation test, the inner surface of the table glass shall not appear condensation fog, and should operate normally.   Chemical resistance test: Citation Specifications: ASTM F 1598-95, ASTM D 1308-87, ASTM D 1308-02 Ingredients: Household chemicals (dirt, dust, oil, fumes and peanut butter, cosmetics, hand cream... Etc.) Time: 24 hours   Corrosion resistance to artificial sweat test: QB/T 1901.2-2006 "Gold alloy covers of shell and its accessories - Part 2 Test for purity, thickness, corrosion resistance and adhesion" Test principle: The artificial sweat is used to contact the object under high temperature (40±2) ℃, and after a long time (not less than 24 hours), the condition of its surface is observed to determine its resistance to sweat corrosion.   Vibration test: Acceleration (19.6m/s^2), frequency 30Hz ~ 120Hz, scanning cycle 1min Requirements: The functions and the LCD display should be complete and normal, and the parts should not be loose and fall off   Drop test: 1m drop lithographic hardwood, once watch side, once surface glass Requirements: Normal function after each impact, no appearance damage [broken glass, case foot bent, case component bent, case broken, button damaged]   Impact test: Impact cone pad material: polytetrafluoroethylene, impact speed 4.43m/s, impact height 1m   Arm swing test: 2 to 10Hz
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  • Drug Stability Test Drug Stability Test
    Mar 12, 2024
    Drug Stability Test The effectiveness and safety of drugs have attracted much attention, and it is also a livelihood issue that the country and the government attach great importance to. The stability of drugs will affect the efficacy and safety. In order to ensure the quality of drugs and storage containers, stability tests should be performed to determine their effective time and storage state. Stability test mainly studies whether the quality of drugs is affected by environmental factors such as temperature, humidity and light, and whether it changes with time and the correlation between them, and studies the degradation curve of drugs, according to which the effective period is presumed to ensure the effectiveness and safety of drugs when used. This article collects the standard information and test methods required for various stability tests for customers' reference. First, drug stability test criteria Storage conditions of drugs:   Storage conditions (Note 2) Long-term experiment 25℃±2℃ / 60%±5%RH or 30℃±2℃ /65%±5% RH Accelerated test 40℃±2℃ / 75%±5%RH Middle test (Note 1) 30℃±2℃ / 65%±5%RH Note 1: If the long-term test condition has been set at 30℃±2℃/65% ±5%RH, there is no middle test; if the long-term storage condition is 25℃±2℃/ 60% ±5%RH, and there is a significant change in the accelerated test, then middle test should be added. And should be assessed against the criteria of "significant change". Note 2: Sealed impervious containers such as glass ampoules can be exempted from humidity conditions. Unless otherwise determined, all tests shall be carried out in accordance with the stability test plan in the interim test. The accelerated test data should be available for six months. The minimum duration of the stability test is 12 months for the middle test and the long-term test.   Store in refrigerator:   Storage conditions Long-term experiment 5℃±3℃ Accelerated test 25℃±2℃ / 60%±5%RH   Stored in freezer:   Storage conditions Long-term experiment -20℃±5℃ Accelerated test 5℃±3℃ If the product containing water or solvents that may be subject to solvent loss is packaged in a semi-permeable container, the stability assessment should be conducted under low relative humidity for a long period of time, or an middle test of 12 months, and an accelerated test of 6 months, in order to prove that the drug placed in the semi-permeable container can withstand the low relative humidity environment.   Containing water or solvents   Storage conditions Long-term experiment 25℃±2℃ / 40%±5%RH or 30℃±2℃ /35%±5% RH Accelerated test 40℃±2℃;≤25%RH Middle test (Note 1) 30℃±2℃ / 35%RH±5%RH Note 1: If the long-term test condition is 30℃±2℃ / 35%±5%RH, there is no middle test.   The calculation of the relative water loss rate at a constant temperature of 40℃ is as follows: Substituted relative humidity (A) Control relative humidity (R) Water loss rate ratio ([1-R]/[1-A]) 60%RH 25%RH 1.9 60%RH 40%RH 1.5 65%RH 35%RH 1.9 75%RH 25%RH 3.0 Illustration: For aqueous drugs placed in semi-permeable containers, the water loss rate at 25%RH is three times that of 75%RH.   Second, Drug stability solutions Common drug stability test criteria (Source: Food and Drug Administration, Ministry of Health and Welfare) Item Storage conditions Long-term experiment 25°C /60% RH Accelerated test 40°C /75%RH Middle test 30°C/65%RH   (1) Wide temperature range test Item Storage conditions Long-term experiment Low or sub-zero temperature conditions Accelerated test Room temperature and humidity or low temperature conditions   (2) Test equipment 1. Constant temperature and humidity test chamber 2. Drug stability test chamber
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  • Reliability of Ceramic Substrate Reliability of Ceramic Substrate
    Oct 18, 2024
    Reliability of Ceramic Substrate Ceramic PCB (Ceramic Substrate) refers to a special process plate where copper foil is directly bonded to the surface (single or double) of alumina (Al2O3) or aluminum nitride (AlN) ceramic substrate at high temperature. The ultra-thin composite substrate has excellent electrical insulation performance, high thermal conductivity, excellent soldering and high adhesion strength, and can be etched into a variety of graphics like PCB board, with great current carrying capacity. Therefore, the ceramic substrate has become the basic material of high-power electronic circuit structure technology and interconnect technology, which is suitable for products with high caloric value (high-brightness LED, solar energy), and its excellent weather resistance can be applied to harsh outdoor environments. Main application products: high power LED carrier board, LED lights, LED street lights, solar inverter Ceramic substrate features: Structure: Excellent mechanical strength, low warping, thermal expansion coefficient close to silicon wafer (aluminum nitride), high hardness, good processability, high dimensional accuracy Climate: Suitable for high temperature and humidity environment, high thermal conductivity, good heat resistance, corrosion and wear resistance, UV& yellowing resistance Chemistry: Lead-free, non-toxic, good chemical stability Electrical: high insulation resistance, easy metallization, circuit graphics and strong adhesion Market: Abundant materials (clay, aluminum), easy to manufacture, low price PCB material thermal characteristics comparison (conductivity) : Glass fiber board (traditional PCB) : 0.5W/mK, aluminum substrate: 1~2.2W/mK, ceramic substrate: 24[alumina]~170[aluminum nitride]W/mK Material heat transfer coefficient (unit W/mK) : Resin: 0.5, alumina: 20-40, silicon carbide: 160, aluminum: 170, aluminum nitride: 220, copper: 380, diamond: 600 Ceramic substrate process classification: According to the line ceramic substrate process is divided into: thin film, thick film, low temperature co-fired multi-layer ceramic (LTCC) Thin Film Process (DPC) : Precise control of component circuit design (line width and film thickness) Thick film process (Thick film) : to provide heat dissipation and weather conditions Low temperature co-fired multilayer ceramic (HTCC) : The use of glass ceramics with low sintering temperature, low melting point, high conductivity of precious metal co-fired characteristics, multi-layer ceramic substrate) and assembly. Low temperature co-fired multilayer ceramics (LTCC) : Stack several ceramic substrates and embed passive components and other ics Thin film ceramic substrate process: · Pretreatment → sputtering → photoresistance coating → exposure development → line plating → film removal · Lamination → hot pressing → degreasing → substrate firing → circuit pattern formation → circuit firing · Lamination → surface printed circuit pattern → hot pressing → degreasing → co-firing · Printed circuit graphics → lamination → hot pressing → degreasing → co-firing Ceramic substrate reliability test conditions: Ceramic substrate high temperature operation: 85℃ Ceramic substrate low temperature operation: -40℃ Ceramic substrate cold and thermal shock: 1. 155℃(15min)←→-55℃(15min)/300cycle 2. 85 ℃ (30 min) please - - 40 ℃ (30 min)/RAMP: 10 min (12.5 ℃ / min) / 5 cycle Ceramic substrate adhesion: Stick to the surface of the board with 3M#600 tape. After 30 seconds, tear quickly in a 90° direction with the surface of the board. Ceramic substrate red ink experiment: Boil for one hour, impermeable Test equipment: 1.High and low temperature humid heat test chamber 2. Three-box gas type cold and heat shock test chamber  
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  • Tablet Reliability Test Tablet Reliability Test
    Oct 16, 2024
    Tablet Reliability Test A Tablet Computer, also known as a Tablet Personal Computer (Tablet PC), is a small, portable personal computer that uses a touch screen as its basic input device. It is an electronic product with strong mobility, and it can be seen everywhere in life (such as waiting stations, trains, high-speed trains, cafes, restaurants, meeting rooms, suburbs, etc.). People carry only simple coat protection or even no, in order to facilitate use, the design reduces the size, so that it can be directly placed in the pocket or handbag, backpack, but the tablet computer in the process of moving will also experience many environmental physical changes (such as temperature, humidity, vibration, impact, extrusion, etc.). Etc.) and natural damage (such as ultraviolet light, sunlight, dust, salt spray, water droplets... It will also cause artificial unintentional injury or abnormal operation and misoperation, and even cause failure and damage (such as: household chemicals, hand sweating, falling, terminal insertion and removal too much, pocket friction, crystal nails... These will shorten the life of the tablet computer, in order to ensure the reliability of the product and extend the service life to improve, we must carry out a number of environmental reliability test projects on the tablet computer, the following relevant tests for your reference. Environmental test project description: Simulate various harsh environments and reliability assessments used by tablet computers to test whether their performance meets the requirements; It mainly includes high and low temperature operation and high and low temperature storage, temperature and condensation, temperature cycle and shock, wet and heat combination test, ultraviolet, sunlight, drip, dust, salt spray and other tests. Operating temperature range: 0℃ ~ 35℃/5% ~ 95%RH Storage temperature range: -10℃ ~ 50℃/10% ~ 90%RH Operating low temperature test: -10℃/2h/ power operation Operating high temperature test: 40℃/8h/ all running Storage low temperature test: -20℃/96h/ shutdown Storage high temperature test: 60℃/96h/ shutdown High temperature test of vehicle storage: 85℃/96h/ shutdown Temperature shock: -40℃(30min)←→80℃(30min)/10cycle Wet heat test: 40℃/95%R.H./48h/ power standby Hot and humid cycle test: 40℃/95%R.H./1h→ramp:1℃/min→-10℃/1h, 20cycles, power standby Wet heat test: 40℃/95%R.H./48h/ power standby Hot and humid cycle test: 40℃/95%R.H./1h→ramp:1℃/min→-10℃/1h, 20cycles, power standby Weather resistance test: Simulation of the most severe natural conditions, solar thermal effect test, each cycle of 24 hours, 8 hours of continuous exposure, 16 hours to keep dark, each cycle radiation amount of 8.96 kWh/m2, a total of 10cycles. Salt spray test: 5% sodium chloride solution/Water temperature 35°C/PH 6.5~7.2/24h/ Shutdown → Pure water wipe shell →55°C/0.5h→ Function test: after 2 hours, after 40/80%R.H./168h. Dripping test: According to IEC60529, in line with IPX2 waterproof rating, can prevent water droplets falling at an Angle of less than 15 degrees from entering the tablet computer and causing damage. Test conditions: water flow rate 3mm/min, 2.5min at each position, checkpoint: after test, 24 hours later, standby for 1 week. Dust Test: According to IEC60529, in line with the IP5X dust class, can not completely prevent the entry of dust but does not affect the device should be the action and anquan, in addition to tablet computers are currently many personal mobile portable 3C products commonly used dust standards, such as: mobile phones, digital cameras, MP3, MP4... Let's wait. Conditions: Dust sample 110mm/3 ~ 8h/ test for dynamic operation After the test, a microscope is used to detect whether dust particles will enter the interior space of the tablet. Chemical staining test: Confirm the external components related to the tablet, confirm the chemical resistance of household chemicals, chemicals: sunscreen, lipstick, hand cream, mosquito repellent, cooking oil (salad oil, sunflower oil, olive oil... Etc.), the test time is 24 hours, check the color, gloss, surface smoothness... Etc., and confirm whether there are bubbles or cracks. Mechanical test: Test the strength of the mechanical structure of the tablet computer and the wear resistance of the key components; Mainly includes vibration test, drop test, impact test, plug test, and wear test... Etc. Fall test: The height of 130cm, free fall on the smooth soil surface, each side fell 7 times, 2 sides a total of 14 times, tablet computer in standby state, each fall, the function of the test product is checked. Repeated drop test: the height of 30cm, free drop on the smooth dense surface of 2cm thickness, each side fell 100 times, each interval of 2s, 7 sides a total of 700 times, every 20 times, check the function of the experimental product, tablet computer is in the state of power. Random vibration test: frequency 30 ~ 100Hz, 2G, axial: three axial. Time: 1 hour in each direction, for a total of three hours, the tablet is in standby mode. Screen impact resistance test: 11φ/5.5g copper ball fell on the center surface of 1m object at 1.8m height and 3ψ/9g stainless steel ball fell at 30cm height Screen writing durability: more than 100,000 words (width R0.8mm, pressure 250g) Screen touch durability: 1 million, 10 million, 160 million, 200 million times or more (width R8mm, hardness 60°, pressure 250g, 2 times per second) Screen flat press test: the diameter of the rubber block is 8mm, the pressure speed is 1.2mm/min, the vertical direction is 5kg force flat press the window 3 times, each time for 5 seconds, the screen should display normally. Screen front flat press test: The entire contact area, the direction of the vertical 25kg force front flat press each side of the tablet computer, for 10 seconds, flat press 3 times, there should be no abnormal. Earphone plug and remove test: Insert the earphone vertically into the earphone hole, and then pull it out vertically. Repeat this for more than 5000 times I/O plug and pull test: The tablet is in standby state, and the plug terminal connector is pulled out, a total of more than 5000 times Pocket friction test: Simulate various materials pocket or backpack, the tablet is repeatedly rubbed in the pocket 2,000 times (friction test will also add some mixed dust particles, including dust particles, yan grass particles, fluff and paper particles for mixing test). Screen hardness test: hardness greater than class 7 (ASTM D 3363, JIS 5400) Screen impact test: hit the most vulnerable sides and center of the panel with a force of more than 5㎏  
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  • Basic troubleshooting methods for high and low temperature test chambers Basic troubleshooting methods for high and low temperature test chambers
    Oct 16, 2024
    Basic troubleshooting methods for high and low temperature test chambers: 1、 High and low temperature testing equipment. In high temperature testing, if the temperature change does not reach the test temperature value, the electrical system can be checked and the faults can be eliminated one by one. If the temperature rises slowly, you need to check the air circulation system to see if the regulating baffle of the air circulation is open normally. Otherwise, check the motor of the air circulation Is the operation normal. If the temperature overshoot is severe, it is necessary to adjust the PID setting parameters. If the temperature rises directly and is protected against overheating, the controller will malfunction and the control instrument must be replaced. 2、 When the high and low temperature test equipment suddenly malfunctions during the test operation, the corresponding fault display prompt and audible alarm prompt will appear on the control instrument. The operator can quickly identify which type of fault it belongs to by referring to the troubleshooting chapter in the operation and use of the equipment, and then ask professional personnel to quickly troubleshoot it to ensure the normal progress of the experiment. Other environmental testing equipment may experience other phenomena during use, so it is necessary to analyze and eliminate them specifically. Regular maintenance and upkeep of environmental testing equipment, regular cleaning of the condenser in the refrigeration system, lubrication of moving parts according to the instructions, and regular maintenance and inspection of the electrical control system are essential tasks 3、 If the low temperature of the high and low temperature testing instrument cannot meet the test indicators, then you need to observe the temperature changes, whether the temperature drops very slowly or there is a trend of temperature recovery after reaching a certain value. The former needs to check whether the working chamber is dried before conducting the low temperature test, so that the working chamber can be kept dry before putting the test sample into the working chamber for further testing. If there are too many test samples placed in the working chamber, which prevent the air in the working chamber from fully circulating, after ruling out the above reasons, you need to consider whether it is a fault in the refrigeration system. In this case, you need to hire professional personnel from the Lab Companion manufacturer for maintenance. The latter phenomenon is caused by poor usage environment of the equipment. The temperature and location of the equipment placement (distance between the box and the wall) must meet the requirements (as specified in the equipment operation instructions). At present, the company's main products include: high and low temperature test chambers, rapid temperature change test chambers, constant temperature and humidity test chambers, and high and low temperature impact test chambers.
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  • Concentrator Solar Cell Concentrator Solar Cell
    Oct 15, 2024
    Concentrator Solar Cell A concentrating solar cell is a combination of [Concentrator Photovoltaic]+[Fresnel Lenes]+[Sun Tracker]. Its solar energy conversion efficiency can reach 31% ~ 40.7%, although the conversion efficiency is high, but due to the long sunward time, it has been used in the space industry in the past, and now it can be used in the power generation industry with sunlight tracker, which is not suitable for general families. The main material of concentrating solar cells is gallium arsenide (GaAs), that is, the three five group (III-V) materials. General silicon crystal materials can only absorb the energy of 400 ~ 1,100nm wavelength in the solar spectrum, and the concentrator is different from silicon wafer solar technology, through the multi-junction compound semiconductor can absorb a wider range of solar spectrum energy, and the current development of three-junction InGaP/GaAs/Ge concentrator solar cells can greatly improve the conversion efficiency. The three-junction concentrating solar cell can absorb energy of 300 ~ 1900nm wavelength relative to its conversion efficiency can be greatly improved, and the heat resistance of concentrating solar cells is higher than that of general wafer-type solar cells.
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  • Conduction Zone of Heat Conduction Zone of Heat
    Oct 14, 2024
    Conduction Zone of Heat Thermal conductivity It is the thermal conductivity of a substance, passing from high temperature to low temperature within the same substance. Also known as: thermal conductivity, thermal conductivity, thermal conductivity, heat transfer coefficient, heat transfer, thermal conductivity, thermal conductivity, thermal conductivity, thermal conductivity. Thermal conductivity formula k = (Q/t) *L/(A*T) k: thermal conductivity, Q: heat, t: time, L: length, A: area, T: temperature difference in SI units, the unit of thermal conductivity is W/(m*K), in imperial units, is Btu · ft/(h · ft2 · °F) Heat transfer coefficient In thermodynamics, mechanical engineering and chemical engineering, the heat conductivity is used to calculate the heat conduction, mainly the heat conduction of convection or the phase transformation between fluid and solid, which is defined as the heat through the unit area per unit time under the unit temperature difference, called the heat conduction coefficient of the substance, if the thickness of the mass of L, the measurement value to be multiplied by L, The resulting value is the coefficient of thermal conductivity, usually denoted as k. Unit conversion of heat conduction coefficient 1 (CAL) = 4.186 (j), 1 (CAL/s) = 4.186 (j/s) = 4.186 (W). The impact of high temperature on electronic products: The rise in temperature will cause the resistance value of the resistor to decrease, but also shorten the service life of the capacitor, in addition, the high temperature will cause the transformer, the performance of the related insulation materials to decrease, the temperature is too high will also cause the solder joint alloy structure on the PCB board to change: IMC thickens, solder joints become brittle, tin whisker increases, mechanical strength decreases, junction temperature increases, the current amplification ratio of transistor increases rapidly, resulting in collector current increases, junction temperature further increases, and finally component failure. Explanation of proper terms: Junction Temperature: The actual temperature of a semiconductor in an electronic device. In operation, it is usually higher than the Case Temperature of the package, and the temperature difference is equal to the heat flow multiplied by the thermal resistance. Free convection (natural convection) : Radiation (radiation) : Forced Air(gas cooling) : Forced Liquid (gas cooling) : Liquid Evaporation: Surface Surroundings Surroundings Common simple considerations for thermal design: 1 Simple and reliable cooling methods such as heat conduction, natural convection and radiation should be used to reduce costs and failures. 2 Shorten the heat transfer path as much as possible, and increase the heat exchange area. 3 When installing components, the influence of radiation heat exchange of peripheral components should be fully considered, and the thermal sensitive devices should be kept away from the heat source or find a way to use the protective measures of the heat shield to isolate the components from the heat source. 4 There should be sufficient distance between the air inlet and the exhaust port to avoid hot air reflux. 5 The temperature difference between the incoming air and the outgoing air should be less than 14 ° C. 6 It should be noted that the direction of forced ventilation and natural ventilation should be consistent as far as possible. 7 Devices with large heat should be installed as close as possible to the surface that is easy to dissipate heat (such as the inner surface of the metal casing, metal base and metal bracket, etc.), and there is good contact heat conduction between the surface. 8 Power supply part of the high-power tube and rectifier bridge pile belong to the heating device, it is best to install directly on the housing to increase the heat dissipation area. In the layout of the printed board, more copper layers should be left on the board surface around the larger power transistor to improve the heat dissipation capacity of the bottom plate. 9 When using free convection, avoid using heat sinks that are too dense. 10 The thermal design should be considered to ensure that the current carrying capacity of the wire, the diameter of the selected wire must be suitable for the conduction of the current, without causing more than the allowable temperature rise and pressure drop. 11 If the heat distribution is uniform, the spacing of the components should be uniform to make the wind flow evenly through each heat source. 12 When using forced convection cooling (fans), place the temperature-sensitive components closest to the air intake. 13 The use of free convection cooling equipment to avoid arranging other parts above the high power consumption parts, the correct approach should be uneven horizontal arrangement. 14 If the heat distribution is not uniform, the components should be sparsely arranged in the area with large heat generation, and the component layout in the area with small heat generation should be slightly denser, or add a diversion bar, so that the wind energy can effectively flow to the key heating devices. 15 The structural design principle of the air inlet: on the one hand, try to minimize its resistance to the air flow, on the other hand, consider dust prevention, and comprehensively consider the impact of the two. 16 Power consumption components should be spaced as far apart as possible. 17 Avoid crowding temperature sensitive parts together or arranging them next to high power consuming parts or hot spots. 18 The use of free convection cooling equipment to avoid arranging other parts above the high power consumption parts, the correct practice should be uneven horizontal arrangement.
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  • IEC-60068-2 Combined Test of Condensation and Temperature and Humidity IEC-60068-2 Combined Test of Condensation and Temperature and Humidity
    Oct 14, 2024
    IEC-60068-2 Combined Test of Condensation and Temperature and Humidity Difference of IEC60068-2 damp heat test specifications In the IEC60068-2 specification, there are a total of five kinds of humid heat tests, in addition to the common 85℃/85%R.H., 40℃/93%R.H. In addition to fixed-point high temperature and high humidity, there are two more special tests [IEC60068-2-30, IEC60068-2-38], these two are alternating wet and humid cycle and temperature and humidity combined cycle, so the test process will change temperature and humidity, and even multiple groups of program links and cycles, applied in IC semiconductors, parts, equipment, etc. To simulate the outdoor condensation phenomenon, evaluate the material's ability to prevent water and gas diffusion, and accelerate the product's tolerance to deterioration, the five specifications were organized into a comparison table of the differences in the wet and heat test specifications, and the test points were explained in detail for the wet and heat combined cycle test, and the test conditions and points of GJB in the wet and heat test were supplemented. IEC60068-2-30 alternating humid heat cycle test This test uses the test technique of maintaining humidity and temperature alternating to make moisture penetrate into the sample and cause condensation (condensation) on the surface of the product to be tested, so as to confirm the adaptability of the component, equipment or other products in use, transportation and storage under the combination of high humidity and temperature and humidity cyclic changes. This specification is also suitable for large test samples. If the equipment and the test process need to keep the power heating components for this test, the effect will be better than IEC60068-2-38, the high temperature used in this test has two (40 ° C, 55 ° C), the 40 ° C is to meet most of the world's high temperature environment, while 55 ° C meets all the world's high temperature environment, the test conditions are also divided into [cycle 1, cycle 2], In terms of severity, [Cycle 1] is higher than [Cycle 2]. Suitable for side products: components, equipment, various types of products to be tested Test environment: the combination of high humidity and temperature cyclic changes produces condensation, and three kinds of environments can be tested [use, storage, transportation ([packaging is optional)] Test stress: Breathing causes water vapor to invade Whether power is available: Yes Not suitable for: parts that are too light and too small Test process and post-test inspection and observation: check the electrical changes after moisture [do not take out the intermediate inspection] Test conditions: Humidity: 95%R.H.[Temperature change after high humidity maintenance](low temperature 25±3℃←→ high temperature 40℃ or 55℃) Rising and cooling rate: heating (0.14℃/min), cooling (0.08 ~ 0.16℃/min) Cycle 1: Where absorption and respiratory effects are important features, the test sample is more complex [humidity not less than 90%R.H.] Cycle 2: In the case of less obvious absorption and respiratory effects, the test sample is simpler [humidity is not less than 80%R.H.] IEC60068-2 damp heat test specification difference comparison table For component type parts products, a combination test method is used to accelerate the confirmation of the test sample's resistance to degradation under high temperature, high humidity and low temperature conditions. This test method is different from the product defects caused by respiration [dew, moisture absorption] of IEC60068-2-30. The severity of this test is higher than that of other humid heat cycle tests, because there are more temperature changes and [respiration] during the test, the cycle temperature range is larger [from 55℃ to 65℃], and the temperature change rate of the temperature cycle is faster [temperature rise: 0.14 ° C /min becomes 0.38 ° C /min, 0.08 ° C /min becomes 1.16 ° C /min], in addition, different from the general humid heat cycle, the low temperature cycle condition of -10 ° C is added to accelerate the breathing rate and make the water condensed in the gap of the substitute freeze, which is the characteristic of this test specification. The test process allows the power test and the applied load power test, but it can not affect the test conditions (temperature and humidity fluctuation, rising and cooling rate) because of the heating of the side product after power. Due to the change of temperature and humidity during the test process, there can not be condensation water droplets on the top of the test chamber to the side product. Suitable for side products: components, metal components sealing, lead end sealing Test environment: combination of high temperature, high humidity and low temperature conditions Test stress: accelerated breathing + frozen water Whether it can be powered on: it can be powered on and external electric load (it can not affect the conditions of the test chamber because of power heating) Not applicable: Can not replace moist heat and alternating humid heat, this test is used to produce defects different from respiration Test process and post-test inspection and observation: check the electrical changes after moisture [check under high humidity conditions and take out after test] Test conditions: damp heat cycle (25 please - 65 + 2 ℃ / 93 + / - 3% R.H.) please - low temperature cycle (25 please - 65 + 2 ℃ / 93 + 3% R.H. - - 10 + 2 ℃) X5cycle = 10 cycle Rising and cooling rate: heating (0.38℃/min), cooling (1.16 ℃/min) Heat and humidity cycle (25←→65±2℃/93±3%R.H.) Low temperature cycle (25←→65±2℃/93±3%R.H. →-10±2℃) GJB150-09 damp heat test Instructions: The wet and heat test of GJB150-09 is to confirm the ability of equipment to withstand the influence of hot and humid atmosphere, suitable for equipment stored and used in hot and humid environments, equipment prone to high humidity, or equipment that may have potential problems related to heat and humidity. Hot and humid locations can occur throughout the year in the tropics, seasonally in mid-latitudes, and in equipment subjected to combined pressure, temperature and humidity changes, with special emphasis on 60 ° C /95%R.H. This high temperature and humidity does not occur in nature, nor does it simulate the dampness and heat effect after solar radiation, but it can find the parts of the equipment with potential problems, but it cannot reproduce the complex temperature and humidity environment, evaluate the long-term effect, and can not reproduce the humidity impact related to the low humidity environment. Relevant equipment for condensation, wet freezing, wet heat combined cycle test: constant temperature and humidity test chamber
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  • AEC-Q100- Failure Mechanism Based on Integrated Circuit Stress Test Certification AEC-Q100- Failure Mechanism Based on Integrated Circuit Stress Test Certification
    Oct 12, 2024
    AEC-Q100- Failure Mechanism Based on Integrated Circuit Stress Test Certification With the progress of automotive electronic technology, there are many complicated data management control systems in today's cars, and through many independent circuits, to transmit the required signals between each module, the system inside the car is like the "master-slave architecture" of the computer network, in the main control unit and each peripheral module, automotive electronic parts are divided into three categories. Including IC, discrete semiconductor, passive components three categories, in order to ensure that these automotive electronic components meet the highest standards of automotive anquan, the American Automotive Electronics Association (AEC, The Automotive Electronics Council is a set of standards [AEC-Q100] designed for active parts [microcontrollers and integrated circuits...] and [[AEC-Q200] designed for passive components, which specifies the product quality and reliability that must be achieved for passive parts. Aec-q100 is the vehicle reliability test standard formulated by the AEC organization, which is an important entry for 3C and IC manufacturers into the international auto factory module, and also an important technology to improve the reliability quality of Taiwan IC. In addition, the international auto factory has passed the anquan standard (ISO-26262). AEC-Q100 is the basic requirement to pass this standard. List of automotive electronic parts required to pass AECQ-100: Automotive disposable memory, Power Supply step-down regulator, Automotive photocoupler, three-axis accelerometer sensor, video jiema device, rectifier, ambient light sensor, non-volatile ferroelectric memory, power management IC, embedded flash memory, DC/DC regulator, Vehicle gauge network communication device, LCD driver IC, Single power Supply differential Amplifier, Capacitive proximity switch Off, high brightness LED driver, asynchronous switcher, 600V IC, GPS IC, ADAS Advanced Driver Assistance System Chip, GNSS Receiver, GNSS front-end amplifier... Let's wait. AEC-Q100 Categories and Tests: Description: AEC-Q100 specification 7 major categories a total of 41 tests Group A- ACCELERATED ENVIRONMENT STRESS TESTS consists of 6 tests: PC, THB, HAST, AC, UHST, TH, TC, PTC, HTSL Group B- ACCELERATED LIFETIME SIMULATION TESTS consists of three tests: HTOL, ELFR, and EDR PACKAGE ASSEMBLY INTEGRITY TESTS consists of 6 tests: WBS, WBP, SD, PD, SBS, LI Group D- DIE FABRICATION RELIABILITY Test consists of 5 TESTS: EM, TDDB, HCI, NBTI, SM The group ELECTRICAL VERIFICATION TESTS consist of 11 tests, including TEST, FG, HBM/MM, CDM, LU, ED, CHAR, GL, EMC, SC and SER Cluster F-Defect SCREENING TESTS: 11 tests, including: PAT, SBA The CAVITY PACKAGE INTEGRITY TESTS consist of 8 tests, including: MS, VFV, CA, GFL, DROP, LT, DS, IWV Short description of test items: AC: Pressure cooker CA: constant acceleration CDM: electrostatic discharge charged device mode CHAR: indicates the feature description DROP: The package falls DS: chip shear test ED: Electrical distribution EDR: non-failure-prone storage durability, data retention, working life ELFR: Early life failure rate EM: electromigration EMC: Electromagnetic compatibility FG: fault level GFL: Coarse/fine air leakage test GL: Gate leakage caused by thermoelectric effect HBM: indicates the human mode of electrostatic discharge HTSL: High temperature storage life HTOL: High temperature working life HCL: hot carrier injection effect IWV: Internal hygroscopic test LI: Pin integrity LT: Cover plate torque test LU: Latching effect MM: indicates the mechanical mode of electrostatic discharge MS: Mechanical shock NBTI: rich bias temperature instability PAT: Process average test PC: Preprocessing PD: physical size PTC: power temperature cycle SBA: Statistical yield analysis SBS: tin ball shearing SC: Short circuit feature SD: weldability SER: Soft error rate SM: Stress migration TC: temperature cycle TDDB: Time through dielectric breakdown TEST: Function parameters before and after stress test TH: damp and heat without bias THB, HAST: Temperature, humidity or high accelerated stress tests with applied bias UHST: High acceleration stress test without bias VFV: random vibration WBS: welding wire cutting WBP: welding wire tension Temperature and humidity test conditions finishing: THB(temperature and humidity with applied bias, according to JESD22 A101) : 85℃/85%R.H./1000h/bias HAST(High Accelerated stress test according to JESD22 A110) : 130℃/85%R.H./96h/bias, 110℃/85%R.H./264h/bias AC pressure cooker, according to JEDS22-A102:121 ℃/100%R.H./96h UHST High acceleration stress test without bias, according to JEDS22-A118, equipment: HAST-S) : 110℃/85%R.H./264h TH no bias damp heat, according to JEDS22-A101, equipment: THS) : 85℃/85%R.H./1000h TC(temperature cycle, according to JEDS22-A104, equipment: TSK, TC) : Level 0: -50℃←→150℃/2000cycles Level 1: -50℃←→150℃/1000cycles Level 2: -50℃←→150℃/500cycles Level 3: -50℃←→125℃/500cycles Level 4: -10℃←→105℃/500cycles PTC(power temperature cycle, according to JEDS22-A105, equipment: TSK) : Level 0: -40℃←→150℃/1000cycles Level 1: -65℃←→125℃/1000cycles Level 2 to 4: -65℃←→105℃/500cycles HTSL(High temperature storage life, JEDS22-A103, device: OVEN) : Plastic package parts: Grade 0:150 ℃/2000h Grade 1:150 ℃/1000h Grade 2 to 4:125 ℃/1000h or 150℃/5000h Ceramic package parts: 200℃/72h HTOL(High temperature working life, JEDS22-A108, equipment: OVEN) : Grade 0:150 ℃/1000h Class 1:150℃/408h or 125℃/1000h Grade 2:125℃/408h or 105℃/1000h Grade 3:105℃/408h or 85℃/1000h Class 4:90℃/408h or 70℃/1000h   ELFR(Early Life failure Rate, AEC-Q100-008) : Devices that pass this stress test can be used for other stress tests, general data can be used, and tests before and after ELFR are performed under mild and high temperature conditions.
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