15 March, 2021
EVT= This is the closest prototype you would have so far to the design intended to launch.
Through this design, you narrow in on any hardware faults and blend your previous looks like and works like prototypes for one that both looks and does something close to what you intend to want.
DVT= This is the design chosen for building from 50- 200 units using a production process similar to the one you’d rely on when the product actually launches.
All the units are then tested in any conceivable relevant way to make sure its both durable and reliable by the end of the process all problems should be corrected.
All final adjustments can still be made here.
- HOW LONG DOES EVT PVT AND DVT TAKE?
- Difference Between EVT and DVT and PVT
- EVT DVP PVT General Goals
- EVT DVT PVT Production
- EVT: Engineering Validation Test?
- DVT : Design Validation Test?
- PVT: Production Validation Test
- EVT DVT PVT Conclusion
- EVT DVT PVT – Frequently Asked Questions
HOW LONG DOES EVT PVT AND DVT TAKE?
As spending too much time or too little time on any of these steps can be harmful to your whole process
- EVT: We advise companies to allocate, as a minimum, 4-5 weeks.
- DVT: This is the most challenging stage. Allocate a minimum of 8 weeks.
- PVT: 4 Weeks is the minimum necessary to run a Production Validation Test.
Please note that depending on your product’s complexity, each test’s time can vary, sometimes considerably.
Your electronic device won’t succeed unless you do all the proper testing before mass manufacturing.
A recent study by CBinsights.com revealed that 97% of new electronic products fail.
A Harvard business school professor argues that so many products fail because they don’t get the job done; remember, users see a product as a tool to get a job done.
So, in that sense, you better make sure your electronic device can do the job users require, or else you’ll face failure.
You accomplish that goal by doing a series of tests throughout the product development process.
In electronics manufacturing, tests can be defined as EVT, DVT, and PVT
Difference Between EVT and DVT and PVT
1. The Goal of an engineering validation test, EVT, is to ensure you meet all functional requirements in the electronics’ electronic requirement matrix.
2. An EVT usually requires 20 to 50 prototype units.
3. In an EVT, up to 40% of the units could fail. This means you have to identify design flaws and solve them before moving forward.
4. Design Validation tests, DVT, can only be done after EVT has been successful. Design validation tests will be challenging and time-consuming.
5. The goal of DVT is to ensure that the product looks right and can stand any environment force while still performing its requirements. Oh, and you also must make sure the production line works.
6. In DVT, batches of your electronic will be manufactured and put under real stress (impact, heat, humidity)
7. In DVT, you must ensure your electronic device meets requirements for any necessary certification.
8. PVT, or production validation test, is a mass production line test.
9. For PVT, you will set up a pilot production line, you will check for any failure along the process and fix it.
10. For the PVT run, you’ll manufacture 5-10% of the first production run.
11. The units manufactured during the PVT run, if okay, can be included in the first production batch for sale
12. During PVT, quality assurance and quality control procedures must already be in place.
If you’re wondering why these three testing stages are often talked about as a group, well, is because
1- EVT DVT PVT are pre mass production stages
2- EVT DVT PVT exist to minimize the risk of errors during mass production
3- EVT DVT PVT seek to find defects in design and process
EVT DVP PVT General Goals
EVT: The goal is to ensure parts fit and work together and that the device performs its core requirements. The units may not look nice and probably won’t do that long.
DVT: The goal is to ensure that your product will match all requirements in design and performance in real environments. You also need to make sure the production line itself works.
Don’t forget to make sure your product meets any necessary certification requirements.
PVT: The goal here is to make sure the production line can properly mass manufacture your electronics
EVT DVT PVT Production
EVT: Units built in the EVT stage, you can refer to them as EVT samples, are made by production tools that may or may not have been finalized.
For example, steel molds for plastic parts that are not yet done, hence the parts’ final texture is not yet the right one for the final product.
During EVT development, design and mechanical engineers teach the production line managers the product’s in and out.
DVT: DVT samples may take much longer to make, per unit, than in the final production process, as the production line itself is being tested.
During DVT, the production line managers teach the production line worker how to assemble the product.
It’s important to use parts from mass production capable processes, no 3D printing here.
The production line you set up must follow proper production procedures.
This is the moment to identify problems in the production line and fix them.
PVT: In the PVT stage, line workers will conduct their work as they would in a large-scale run. The production line will move slowly at first and then start ramping up.
EVT: Engineering Validation Test?
An EVT is a test done during the prototyping stage of an electronic device.
Electronic engineers will put together an actual working sample of the electronic, using the final product’s intended components and materials.
If you already did a looks like prototype to test design and appearance, and a works like prototype, to prove product functions, both must be put together for EVT.
The EVT will be used to validate that the prototype can perform all tasks as specified in the Requirements Traceability Matrix.
Before moving forward, you need to make sure the EVT units can perform all tasks; users expect it to perform. Otherwise, you’re stuck.
Apart from individually testing a product’s specific functionalities, some standard tests done during EVT are
List of EVT Tests
- Functional Test
- Power Measurement
- Signal Quality Test
- Conformance Test
- Electromagnetic Interference (EMI)
- Thermal and four corner test
- Basic parametric measurements, specification verification
Regarding how many EVT units you need to work on, well, it depends on the complexity of the device and the BOM cost.
The average electronic will need around at least 20 EVT prototypes to go through an engineering validation test and reach a satisfactory conclusion.
Remember that you’re testing how well units perform the required task/tasks.
If you’re manufacturing a spy cam that takes HD pics, then the goal is to make sure the camera takes HD pics.
Identify all issues and fix them before moving on to Design Validation Test – DVT
DVT : Design Validation Test?
This test seeks to guarantee that an electronic device can meet cosmetic and environmental requirements while still performing its core task/s.
Also, during DVT, you need to test the production line itself.
For DVT you need to use real products in the right dimensions and materials and components suitable for mass manufacturing.
Your electronic device will be produced in batches and will be under real pressure.
Here we are talking about dropping it from a certain height, burning it, checking its waterproofing, etc.
A wide range of tests will be required to determine whether the product is ready for production or not.
Vibration and Shock Testing
You want to make sure its appearance is resilient and will last long enough; you’ll even have to check the painting to see how easily scratches, etc.
DVT also deals with certifications such as CE, FCC, UL, etc.
For different countries, there are different certifications and product standards.
For example, in Europe, you usually need at least RoHS and CE, and sometimes UL if your product is directly connected to a DC power source.
Hence, the target countries that you have listed in your Requirements Traceability Matrix will tell you the certifications you must meet before selling your product on the market.
You reach a successful DVT when you produce units with full functionalities, with components intended for mass manufacturing, and that can be used for certification, and which production line works fine.
List of DVT Tests
- Functional testing (including usability)
PVT: Production Validation Test
PVT is the last step before mass production. During this stage, the product design is frozen because it’s already been validated by EVT and DVT.
It’s common to find assembly problems that could end up in a product design change to optimize the assembly line.
All components, materials, and processes (packaging, logistics, freight, quality assurance control) must be at the mass production stage.
At the end of the PVT stage, all units must be inspected and validate that the end product meets all design and functionality requirements.
Key Concerns in PVT
1- Production line installation
2- Product Line Review
3- Production test
4- First Article Inspection
Identify weak points, fix them, and test again.
At the end of a successful PVT, you’re ready for full-blown mass manufacturing. Mass manufacturing requires constant monitoring.
EVT DVT PVT Conclusion
So, there you go, EVT DVT PVT, they’re crucial stages before going into mass manufacturing.
During our years of work in electronics manufacturing, we can confidently say that it’s DVT the most challenging and time-consuming stage.
There’s no faster way to get out of the DVT stage, with a good outcome, than by having a group of experienced engineers in your project that have made sure they implement DFM from the very beginning.
EVT DVT PVT – Frequently Asked Questions
What is EVT?
EVT means engineering validation test. The goal of an evt is to ensure that the parts of an electronic device fit together, and it functions as intended.
What is EVT PVT DVT Testing?
EVT, DVT, and PVT testing are pre mass manufacture stages whose common goal is to decrease the risk of failure during mass manufacturing.
What Does EVT DVT PVT mean?
- EVT means Engineering Validation Test
- DVT means Design Validation Test
- PVT means Production Validation Test
What is DVT testing?
DVT testing is a rigorous process in which an electronic is put under a lot of stress across different tests to make sure it can perform its function in real use environments.
DVT testing also includes building and testing the production line.