What is the difference between EVT, DVT and PVT?

EVT proves the design works, DVT proves it works reliably and passes certification, and PVT proves the production line can build it repeatedly at the target quality.

Can a project skip a stage?

Small, simple products sometimes merge stages, but skipping validation moves the discovery of problems to after tooling or after shipping, where fixing them costs far more.

What should I receive after each stage?

A test report against the agreed criteria, the build files at that revision, a list of open issues and the decision on whether to proceed.

When is tooling committed?

Usually after EVT confirms the design, with hard tooling in place for PVT. DVT builds often use softer tooling or first-shot parts.

EVT vs DVT vs PVT: What Each Hardware Build Stage Delivers

Between a working prototype and a product that ships by the thousand sit three validation builds. Teams that understand them budget the schedule correctly. Teams that do not meet the same problems late and expensively.

EVT: does the design work?

Engineering validation builds a small number of units to prove that the architecture does what the specification says. Power, signal quality, thermal behaviour, radio performance and the core features are tested. Parts and mechanics may still change, and that is expected.

You should receive: a test report against the specification, a list of design changes and the decision to freeze or revise the design.

DVT: does it work reliably?

Design validation builds units from near-final parts and tooling. Reliability, drop and environmental tests are run, and certification testing begins in earnest. The question moves from whether it works to whether it keeps working, for every unit and in the field.

You should receive: reliability and certification results, an updated bill of materials and a go decision for production tooling.

PVT: can the line build it?

Production validation runs the real line, with production tooling, fixtures and operators. The goal is yield and repeatability: assembly time, test coverage, failure analysis and packaging. This is where a design that worked in the lab proves it can be built the same way every time.

You should receive: yield data, the production test plan, the packaging and shipping approval and the release to mass production.

What goes wrong when a stage is skipped

Skipping EVT: architecture problems appear after parts are bought.
Skipping DVT: failures appear in certification or in customers hands, after tooling is committed.
Skipping PVT: the first production lot becomes the validation, and its defects are shipped.

Where tooling fits

Tooling is usually committed once EVT confirms the design, with production tooling in place before PVT. A change after that point costs a mould round, which is why DVT exists.

We describe how these stages sit inside a project on the demo to production page, and how a development project is organised on the services page.

3CBAY develops connected hardware in Shenzhen with design, firmware, app, server and production in one team. Planning a build? Tell us what you are building.