Vibrational Verification for Functionality(VVF)
In the vibration generated during transportation, freight boxes are susceptible to complex dynamic pressures, and the resonant response generated is violent, which may cause packaging or product failure. Identifying the critical frequency and the type of pressure on the package will minimize this failure. Vibration testing is the assessment of the vibration resistance of components, components and complete machines in the expected transport, installation and use environment.
Common vibration modes can be divided into sinusoidal vibration and random vibration. Sinusoidal vibration is a test method often used in the laboratory, which mainly simulates the vibration generated by rotation, pulsation and oscillation, as well as the resonance frequency analysis and resonance point residence verification of the product structure. It is divided into sweep frequency vibration and fixed frequency vibration, and its severity depends on the frequency range, amplitude value and test duration. Random vibration is used to simulate the overall structural seismic strength assessment of the product and the shipping environment in the packaged state, with the severity depending on the frequency range, GRMS, test duration and axial orientation.
Vibration can not only loosen the lamp components, so that the internal relative displacement, resulting in de-welding, poor contact, poor working performance, but also make the components produce noise, wear, physical failure and even component fatigue.
To this end, Lab Companion launched a professional "LED lamp vibration test" business to simulate the vibration or mechanical shock that may occur in the actual transportation, installation and use environment of the lamp, evaluate the vibration resistance of the LED lamp and the stability of its related performance indicators, and find the weak link that may cause damage or failure. Improve the overall reliability of LED products and improve the failure status of the industry due to transportation or other mechanical shocks.
Service customers: LED lighting factory, lighting agents, lighting dealers, decoration companies
Test method:
1, the LED lamp sample packaging placed on the vibration test bench;
2, the vibration speed of the vibration tester is set to 300 RPM, the amplitude is set to 2.54 cm, start the vibration meter;
3, the lamp according to the above method in the upper and lower, left and right, front and back three directions respectively test for 30 minutes.
Results evaluation: After the vibration test, the lamp can not occur parts falling off, structural damage, lighting and other abnormal phenomena.
ESS Environmental Stress Screening Test Chamber
The full horizontal air supply system from right to left with large air volume is adopted, so that all specimen cars and specimens on the test are charged and divided, and the heat exchange is completed evenly and quickly.
◆ The utilization rate of test space is as high as 90%
◆ The special design of "uniform horizontal air flow system" of ESS equipment is the patent of Ring measurement.
Patent number: 6272767
◆ Equipped with air volume regulation system
◆ Unique turbine circulator (air volume can reach 3000~ 8000CFM)
◆ Floor type structure, convenient loading and unloading of tested products
◆ According to the special structure of the tested product, the box suitable for installation is used
◆ The control system and refrigeration system can be separated from the box, which is easy to plan or do noise reduction in the laboratory
◆ Adopt cold balance temperature control, more energy saving
◆ Equipment adopts the world's top brand Sporlan refrigeration valve with high reliability and long life
◆ The refrigeration system of the equipment adopts thickened copper pipe
◆ All the strong electric parts are made of high temperature resistant wires, which has higher safety
Reliability Testing Acceleration Testing
Most semiconductor devices have lifetimes that extend over many years at normal use. However, we cannot wait years to study a device; we have to increase the applied stress. Applied stresses enhance or accelerate potential fail mechanisms, help identify the root cause, and help labcompanion take actions to prevent the failure mode.
In semiconductor devices, some common accelerants are temperature, humidity, voltage, and current. In most cases, the accelerated testing does not change the physics of the failure, but it does shift the time for observation. The shift between accelerated and use condition is known as ‘derating.’
Highly accelerated testing is a key part of JEDEC based qualification tests. The tests below reflect highly accelerated conditions based on JEDEC spec JESD47. If the product passes these tests, the devices are acceptable for most use cases.
Temperature Cycle
Per the JESD22-A104 standard, temperature cycling (TC) subjects the units to extreme high and low temperatures transitions between the two. The test is performed by cycling the unit's exposure to these conditions for a predetermined number of cycles.
High Temperature Operating Life (HTOL)
HTOL is used to determine the reliability of a device at high temperature while under operating conditions. The test is usually run over an extended period of time according to the JESD22-A108 standard.
Temperature Humidity Bias/Biased Highly Accelerated Stress Test (BHAST)
According to the JESD22-A110 standard, THB and BHAST subject a device to high temperature and high humidity conditions while under a voltage bias with the goal of accelerating corrosion within the device. THB and BHAST serve the same purpose, but BHAST conditions and testing procedures enable the reliability team to test much faster than THB.
Autoclave/Unbiased HAST
Autoclave and Unbiased HAST determine the reliability of a device under high temperature and high humidity conditions. Like THB and BHAST, it is performed to accelerate corrosion. Unlike those tests, however, the units are not stressed under a bias.
High Temperature Storage
HTS (also called Bake or HTSL) serves to determine long-term reliability of a device under high temperatures. Unlike HTOL, the device is not under operating conditions for the duration of the test.
Electrostatic Discharge (ESD)
Static charge is an unbalanced electrical charge at rest. Typically, it is created by insulator surfaces rubbing together or pulling apart; one surface gains electrons, while the other surface loses electrons. The result is an unbalanced electrical condition known as static charge.
When a static charge moves from one surface to another, it becomes Electrostatic Discharge (ESD) and moves between the two surfaces in a form of a miniature lightning bolt.
When a static charge moves, it becomes a current that can damage or destroy gate oxide, metal layers, and junctions.
JEDEC tests ESD in two different ways:
1. Human Body Mode (HBM)
A component level stress developed to simulate the action of a human body discharging accumulated static charge through a device to ground.
2. Charged Device Model (CDM)
A component level stress that simulates charging and discharging events that occur in production equipment and processes, per the JEDEC JESD22-C101 specification.
Conversion Between Accelerated Aging of Xenon Lamp Aging Test Chamber And Outdoor Aging
Generally speaking, it is difficult to have a detailed positioning and conversion formula for the conversion between accelerated aging of xenon lamp aging test chamber and outdoor aging. The biggest problem is the variability and complexity of the outdoor environment. The variables that determine the relationship between xenon lamp aging test chamber exposure and outdoor exposure include:
1. Geographical latitude of outdoor aging exposure sites (closer to the equator means more UV).
2. Altitude (Higher altitude means more UV).
3. Local geographical characteristics, such as the wind can dry the test sample or close to water will produce condensation.
4. Random changes in climate from year to year can lead to a 2:1 change in aging at the same location.
5. Seasonal changes (e.g., winter exposure may be 1/7 of summer exposure).
6. Direction of the sample (5° south vs. vertical facing north)
7. Sample insulation (outdoor samples with insulated backing age 50% faster than uninsulated samples).
8. Working cycle of xenon lamp aging box (light time and wet time).
9. The working temperature of the test chamber (the higher the temperature, the faster the aging).
10. Test the uniqueness of the sample.
11. Spectral Intensity Distribution (SPD) of laboratory light sources
Objectively speaking, accelerated aging and outdoor aging have no convertibility, one is a variable, one is a fixed value, the only thing to do is to obtain a relative value, rather than an absolute value. Of course, it is not to say that relative values have no effect; on the contrary, relative values can also be very effective. For example, you will find that a slight change in design may double the durability of standard materials. Or you may find the same looking material from multiple suppliers, some of which age quickly, most of which take a moderate amount of time to age, and a smaller amount that ages after longer exposure. Or you may find that less expensive designs have the same durability against standard materials that have satisfactory performance over actual service life, such as 5 years.
Thin Film Solar Cell
Thin film solar cell is a kind of solar cell manufactured by thin film technology, which has the advantages of low cost, thin thickness, light weight, flexibility and bendability. It is usually made of semiconductor materials such as copper indium gallium selenide (CIGS), cadmium telluride (CdTe), amorphous silicon, gallium arsenide (GaAs), etc. These materials have high photoelectric conversion efficiency and can generate electricity under low light conditions.
Thin film solar cells can be used in inexpensive glass, plastic, ceramics, graphite, metal sheet and other different materials as substrates to manufacture, forming a film thickness that can generate voltage only a few μm, so the amount of raw materials can be significantly reduced than silicon wafer solar cells under the same light receiving area (thickness can be lower than silicon wafer solar cells more than 90%). At present, the conversion efficiency of up to 13%, thin film solar cells are not only suitable for flat structure, because of its flexibility can also be made into non-plane structure, has a wide range of application prospects, can be combined with buildings or become a part of the building body.
Application of thin film solar cell product:
Translucent solar cell modules: Building Integrated Solar Energy Applications (BIPV)
Application of thin film solar energy: portable folding rechargeable power supply, military, travel
Applications of thin film solar modules: roofing, building integration, remote power supply, defense
Features of thin film solar cells:
1. Less power loss under the same shielding area (good power generation under weak light)
2. The loss of power under the same illumination is less than that of wafer solar cells
3. Better power temperature coefficient
4. Better light transmission
5. High cumulative power generation
6. Only a small amount of silicon is needed
7. There is no internal circuit short circuit problem (the connection has been built in the series battery manufacturing)
8. Thinner than wafer solar cells
9. Material supply is secure
10. Integrated use with building materials (BIPV)
Solar cell thickness comparison:
Crystalline silicon (200 ~ 350μm), amorphous film (0.5μm)
Types of thin film solar cells:
Amorphus Silicon (a-Si), Nanocrystalline Silicon (nc-Si), Microcrystalline Silicon, mc-Si), compound semiconductors II-IV [CdS, CdTe(cadmium telluride), CuInSe2], Dye Sensitized Solar cells, Organic/polymer solar cells, CIGS (Copper indium selenide)... Etc.
Thin-film solar module structure diagram:
Thin film solar module is composed of glass substrate, metal layer, transparent conductive layer, electrical function box, adhesive material, semiconductor layer... And so on.
Reliability test specification for thin film solar cells:
IEC61646(Thin-film solar photoelectric module test standard), CNS15115(thin-film silicon onshore solar photoelectric module design validation and type approval)
Temperature & humidity test chamber of Lab Companion
Temperature & humidity test chamber series, passed the CE certification, offer 34L, 64L, 100L, 180L, 340L, 600L, 1000L, 1500L and other volume models to meet the needs of different customers. In design, they use environment-friendly refrigerant and high-performance refrigeration system, parts and components are used in the international famous brand.
Heat Pipe Reliability Test
Heat pipe technology is a heat transfer element called "heat pipe" invented by G.M. rover of Los Alamos National Laboratory in 1963, which makes full use of the principle of heat conduction and the rapid heat transfer properties of the refrigeration medium, and transfers the heat of the heating object quickly to the heat source through the heat pipe. Its thermal conductivity exceeds that of any known metal. Heat pipe technology has been widely used in aerospace, military and other industries, since it has been introduced into the radiator manufacturing industry, making people change the design idea of the traditional radiator, and get rid of the single heat dissipation mode that simply relies on high air volume motor to obtain better heat dissipation effect. The use of heat pipe technology makes the radiator even if the use of low speed, low air volume motor, can also get satisfactory results, so that the noise problem plagued by air cooling heat has been well solved, opening up a new world in the heat dissipation industry.
Heat pipe reliability test conditions:
High temperature stress screening test: 150℃/24 hours
Temperature cycling test:
120℃(10min)←→-30℃(10min), Ramp: 0.5℃, 10cycles 125℃(60min)←→-40℃(60min), Ramp: 2.75℃, 10cycles
Thermal shock test:
120℃(2min)←→-30℃(2min), 250 cycles
125℃(5min)←→-40℃(5min), 250 cycles
100℃(5min)←→-50℃(5min), 2000 cycles(check once after 200 cycles)
High temperature and high humidity test:
85℃/85%R.H./1000 hours
Accelerated aging test:
110℃/85%RH/264h
Other heat pipe test items:
Salt spray test, strength (blasting) test, leakage rate test, vibration test, random vibration test, mechanical shock test, helium combustion test, performance test, wind tunnel test
Get A Quote
IPv6 network supported