Key Takeaways
- Discontinuations (EOL) are announced via PCNs and PDNs – the earlier you spot them, the more options you have.
- The main responses are a last time buy, an alternative part (form-fit-function) or a redesign.
- Proactive obsolescence management starts with component selection and continues with regular BOM monitoring.
Electronic products in industry, machine building or medical technology are often manufactured for ten years or longer. The semiconductors they contain frequently have much shorter lifecycles. Sooner or later almost every assembly faces the same problem: a component is discontinued. In this third part of our series we show how to detect discontinuations early, what options you have and how structured obsolescence management prevents production stoppages.
What does end of life (EOL) mean for electronic components?
A component reaches end of life (EOL) when its manufacturer decides to stop producing it. Reasons include the move to new manufacturing processes, the closure of a production line, low demand or new regulatory requirements. For the user this means: after a final ordering deadline, the part is no longer available through authorised distribution.
Typical lifecycle stages
| Status | Meaning | Action required |
|---|---|---|
| Active | Part is regularly produced and sold | None, monitor regularly |
| NRND | “Not Recommended for New Designs” – still available but no longer recommended for new developments | Check alternatives, do not use in new designs |
| Last time buy | Discontinuation announced, final ordering window open | Calculate remaining demand, make a decision |
| Obsolete / EOL | Production stopped, no regular supply | Alternative, redesign or verified remaining stock |
PCN and PDN: how manufacturers announce changes
Manufacturers communicate changes through two types of notice:
- PCN (Product Change Notification): announces changes to a product, such as material, manufacturing site, package or datasheet values.
- PDN (Product Discontinuance Notice): announces the discontinuation and usually states the dates for last order and last shipment.
The time between announcement and last order differs by manufacturer and industry. What matters is that these notices reach you and are assessed. Companies that only order through distributors often learn of a discontinuation when the part can no longer be delivered.
Your options when a part is discontinued
1. Last time buy (LTB)
With a last time buy you purchase the expected remaining demand for the rest of the product’s life. For a realistic calculation you need:
- the expected demand until the planned end of the product
- demand for service, repair and spare parts
- a safety margin for scrap and planning uncertainty
- the cost of tied-up capital and storage
Storage conditions are crucial for long-term storage. Moisture-sensitive parts must be dry-packed or stored according to their MSL (moisture sensitivity level) so that solderability and reliability are preserved.
2. Alternative part (second source)
There are often parts from other manufacturers that are functionally equivalent. A distinction is made between:
- Drop-in replacement or form-fit-function (FFF): same package, same pinout, same or better electrical properties – usable without changing the layout.
- Functional replacement: same function but different package or pinout – requires a layout change.
An alternative part must be technically verified: electrical parameters, temperature range, timing, package tolerances and, where applicable, qualifications such as AEC-Q standards for automotive. Safety-related or certified products may also require requalification.
3. Redesign
If no suitable replacement exists or several parts are affected at once, a redesign is often the more economical solution. It offers the opportunity to modernise the assembly and switch to parts with long-term availability.
4. Remaining stock from the open market
Discontinued parts are often still held by independent brokers. However, the risk of counterfeits and improperly stored goods rises significantly. Such purchases should only be made with traceable origin and suitable testing – learn more about our approach on the quality & compliance page.
Proactive obsolescence management: prevent instead of react
The standard IEC 62402 describes obsolescence management as a systematic process across the entire product lifecycle. For small and medium-sized companies, the following measures have proven particularly effective:
- Forward-looking component selection: in new designs, use parts that are new to the market, offered by several manufacturers or covered by a manufacturer longevity programme.
- Multi-sourcing in the design: record approved alternatives in the BOM and design footprints so that several variants fit.
- Regular BOM monitoring: check the lifecycle status of all lines at fixed intervals, especially for long-lived products.
- Identify critical parts: monitor single-source components such as microcontrollers, FPGAs or special ICs particularly closely.
- Clear responsibilities: define who assesses PCNs and who decides on LTB, replacement or redesign.
How Intelligent Components supports you
Every review of your BOM through our BOM sourcing service also assesses lifecycle status and potential discontinuation risks. If a part is not available, we research compatible alternatives and verify their technical equivalence. This keeps your electronic components sourceable in the long term. The foundation is a complete BOM – part 1 of the series shows what it should look like.
Frequently Asked Questions About Component Discontinuation
What does NRND mean for electronic components?
NRND stands for “Not Recommended for New Designs”. The part is still available, but the manufacturer no longer recommends it for new developments. A discontinuation in the foreseeable future is likely.
What is a last time buy?
A last time buy is the final order of a discontinued part before the deadline stated by the manufacturer. The expected remaining demand for production and service is purchased in one go.
How do I find a replacement part?
Cross-references are used to find parts from other manufacturers with the same function, package and comparable parameters. The electrical and mechanical data must then be technically reviewed and, if necessary, tested in the application.
How far in advance are discontinuations announced?
This varies by manufacturer and product group. Manufacturers announce discontinuations through a product discontinuance notice that states the deadlines for last order and last delivery.
Is your BOM future-proof? Send us your BOM – we check the availability and lifecycle status of every line.
