A part on your BOM just went end-of-life. Here's the order to work the problem in, from the cheapest fix to the last resort, and how to keep counterfeits out along the way.
Every semiconductor has a life cycle, and eventually the manufacturer stops making it. A fab retires an old process node, a product line gets consolidated, or demand drops below what's worth producing. For consumer products that's rarely a problem. For industrial, medical, aerospace, and infrastructure gear that ships for fifteen or twenty years, a single obsolete part can put a whole production line at risk.
The good news: obsolescence is a managed problem, not a dead end. Work it in this order and you'll usually find a path that doesn't involve a redesign.
Obsolescence is almost always announced before it happens. When a manufacturer plans to discontinue a part, it issues a PCN (Product Change Notification) or PDN (Product Discontinuance Notification), usually 6 to 12 months ahead of the last ship date. Before you do anything else, pin down where the part actually sits:
If you're still inside the last-time-buy window, you have the simplest option available: buy the parts while the factory is still making them.
A last-time buy means purchasing enough inventory to cover production and service for the remaining life of your product. This is the cleanest outcome because the parts are still factory fresh and usually carry clear manufacturer-channel records. The hard part is the quantity: buy too few and you're back here in two years paying broker prices, buy too many and you're holding dead stock and tying up cash.
If the last-time-buy window has closed, the next question is whether you even need the exact part. A form-fit-functionalternate is a different part number that matches the original's footprint, electrical behavior, and environmental ratings closely enough to drop in.
For a genuinely obsolete part with no drop-in alternate, the safest source is the authorized aftermarket. These are companies the original manufacturer has licensed to continue production, often using the original tooling, wafers, and test programs. Rochester Electronics is the best-known example. This type of channel is valued for authentic parts and documented manufacturer-channel traceability, which is exactly what you want on a critical line.
When none of the above works, the independent (open) market is a legitimate and often necessary source for obsolete parts. It is also where counterfeit risk is highest, precisely because scarcity is what counterfeiters exploit. This is the moment to be disciplined, not desperate:
Obsolete and allocation-constrained parts are the single most counterfeited category, so provenance matters more here than anywhere else. Our companion guide walks through exactly how to verify a part is genuine: How to verify electronic components are authentic.
If a part is truly unobtainable, the remaining options are engineering ones: redesign the board around a current part, or use a drop-in emulation of the original built on modern silicon. Redesign is the most expensive and slowest path, which is why it sits at the bottom of the list, but for a long-life product it is sometimes the right call.
The cheapest obsolescence problem is the one you see coming. A little proactive work turns a fire drill into a planned buy:
For a hard-to-find or end-of-life BOM line, we search potential supplier routes for the specified part and quantity, compare suitable quotations, and ask what source documentation is available. After receipt, we visually check external packaging condition and photograph the packaging and labels. This does not include X-ray, decapsulation, electrical testing, or laboratory authentication, and we do not promise that every requested line can be sourced.
Work the problem from cheapest fix to last resort. Check for a last-time-buy window and cover your remaining demand while the manufacturer is still shipping. In parallel, look for an approved form-fit-function alternate. Only when neither is available do you move to the authorized aftermarket and then the vetted open market, where documentation and counterfeit avoidance become critical.
A last-time buy is a final purchase of a part before the manufacturer stops production, sized to cover your expected demand through end of life or until a redesign lands. Base the quantity on your production forecast plus service and spares, and account for shelf life and storage conditions. Decide whether your company or a suitable third-party logistics provider will hold and release the material.
Use suppliers who can explain their sourcing channel and work to a counterfeit-avoidance standard. Request the available Certificate of Conformance and traceability records, verify date and lot codes against the paperwork, and inspect packaging and markings. If a price sits far below every other quote for a scarce part, treat it as a warning rather than a win.
Send us the part number and your remaining demand. We'll come back with an initial review and the next questions. Suitable source options, timing, and available documentation are confirmed separately for each quote.