A startup wins a design-in by getting its part onto the OEM's bill of materials before the schematic freezes. The OEM's engineers need a working evaluation kit, a reference design they can copy, fast answers from a field application engineer, qualification data their quality team accepts, and a credible supply plan. Revenue comes later, when the OEM's product ramps.
What are the stages of a design-in, and what does the OEM need at each one?
A design-in is the period when the OEM's engineers test your part and build it into their circuit. The design win is the moment they commit to your part for a named product. Ambarella's 10-K, filed in March 2026, describes a multi-month process with the customer's system designers and management that ends in that decision. Once a part is designed in, it usually stays for the life of the product.
| Stage | What happens at the OEM | What the OEM needs from you |
|---|---|---|
| Evaluation kit | An engineer tests your part on the bench against the datasheet | A board that works on first power-up, schematics, drivers, a datasheet with measured data |
| Reference design | The team copies a proven circuit into its first prototype | Layout files, a reference BOM, application notes for their use case, known-good firmware |
| FAE support | Prototype bring-up, debug and margin testing | An engineer who answers the same day and visits the lab when a board fails |
| Qualification | The quality team reviews reliability data and your supply chain | Stress-test reports to the end market's standard, a change notification process, audit access |
| Design win | Your part goes onto the approved BOM for one program | Lifetime pricing, lead times, a second-source or continuity plan |
| Production ramp | The OEM builds in volume | Allocation, forecast reviews, fast failure analysis on field returns |
Startups most often underfund the FAE stage. A part that works on your bench and fails on the customer's prototype loses the socket, and the OEM rarely explains why.
How long does it take to turn a design win into revenue?
Plan for one to four years, based on the filings below, and fund the company for the long end:
- Ambarella's 10-K (March 2026) says volume production may begin 12 to 18 months after a design win, with longer cycles in automotive, industrial and robotics than in IoT.
- Allegro MicroSystems' 10-K (May 2026) says the time from design initiation to sales for new products is typically two to four years.
- Navitas Semiconductor's 10-K (February 2026) says revenue from a design win typically arrives one year or more later, if ever.
- indie Semiconductor's 10-K (February 2026) says it can stay in production with a customer for up to seven years or longer on a single design, and that losing a design-in can shut it out of a customer for several years.
Automotive adds a qualification gate. AEC-Q100 Rev J1, published by the Automotive Electronics Council in March 2026, defines the stress tests an IC must pass for car use. Its high temperature operating life test, for example, takes 77 parts from each of 3 lots with zero failures, and runs 1,000 hours at 125 degrees Celsius ambient for a Grade 1 part. The council runs no certification body. Each supplier qualifies its own part and submits the data to the customer to verify, so your qualification report is a sales document and the OEM's quality engineer reads every page.
Our view: if your runway is shorter than the cycle in Allegro's disclosure, lead with consumer and industrial programs that ship sooner, and run automotive as a second track.
Who decides inside the OEM?
Five functions take part, and any of them can stop the deal:
- System architect. Draws the block diagram and decides whether your part category belongs in the product at all. Win this person first.
- Hardware design engineer. Runs your eval kit, builds the prototype, and becomes your champion or your blocker.
- Component engineer. Checks the datasheet, package, lifecycle status and the approved vendor list. Make the paperwork easy.
- Purchasing. Negotiates price, lead time and terms, asks about a second source, and checks your balance sheet.
- Quality and reliability. Reviews qualification data, audits your supply chain, and owns failure analysis after launch.
Often a second company does the design work. Ambarella's March 2026 10-K says its sales effort targets the OEM, while an ODM or Tier-1 supplier may handle the design on the OEM's behalf. Map both organizations. Start with engineering and bring in purchasing last. A startup that opens with purchasing gets a price comparison against the incumbent with no technical reason to switch.
Why do distributors and field application engineers matter so much?
Most chip revenue moves through distribution, so distributor staff often decide which parts an OEM engineer sees first.
- Lattice Semiconductor's 10-K (February 2026) reports that distributors accounted for 84% of net revenue in fiscal 2025.
- Allegro's 10-K (May 2026) reports net sales to distributors of 55.0% in fiscal 2026.
- Ambarella's 10-K (March 2026) reports that one distributor, its sales representative and fulfillment partner in Asia outside Japan, accounted for about 70% of revenue in fiscal 2026.
Distributors stock parts, extend credit to small OEMs, and send their own FAEs to customer labs. Both Lattice and Navitas, in filings from February 2026, list the availability of field application engineering resources as a factor in their results. Our position: a chip startup's second commercial hire should be an FAE, ahead of a second account executive.
How do second-source requirements and supply risk change the deal?
Purchasing will ask what happens if your fab or package house goes away. Navitas' 10-K (February 2026) says it relied on TSMC as its sole supplier of GaN wafers, and that TSMC announced on July 1, 2025 that it would stop GaN production in July 2027. Navitas responded with buffer inventory and other supply arrangements. Lattice (February 2026) qualified two assembly partners and second-sources where volume and customer requirements make it necessary.
A changed supply chain also costs the customer time. AEC-Q100 (March 2026) requires requalification when a supplier changes a product or process in a way that could affect form, fit, function, quality or reliability. Bring a written answer to the first purchasing meeting: buffer stock commitments, a qualified second assembly site or a plan for one, a product longevity statement, and last-time-buy terms.
What should a startup do this quarter to earn its first design-in?
The buyers have money, and the seller field is crowded. The Semiconductor Industry Association reported in October 2026 that global chip sales reached $159.7 billion in August 2026, up 144.3% on August 2025.
- Pick one application in one end market. Build the eval kit and reference design for that application only.
- Write application notes for the integration problems your first evaluators hit, and publish them where engineers search.
- List OEM programs with a product refresh coming, then name the architect and the hardware lead on each. Our guide on how a technical founder builds a target account list covers the method.
- Find the Tier-1 or ODM that does the design work for your target OEMs, and get your part onto their reference platform.
- Sign a franchise distributor in your target region and register every opportunity with them.
- Hire or contract an FAE before you add another salesperson.
- Prepare the qualification data pack and a supply continuity letter before purchasing asks for them.
- Track each design-in by stage, with expected ramp date and annual volume, so the board can see when revenue lands.
A design-in that stalls after the prototype often has the same causes we cover in why deep tech pilots fail to convert into contracts.
For an outside read on your OEM target list and design-in pipeline, start with The Diagnostic.