The email arrives on an ordinary Tuesday: a manufacturer is discontinuing a part that sits on three of your boards. The temptation is to do one of two things – panic-buy whatever is available, or ignore the notice because production is fine this quarter. Both are expensive.
An end-of-life notice is not a disaster. It is a start date for a project with a deadline. This guide walks through the sequence procurement and engineering teams use to handle EOL components: decode the notice, decide between a last-time buy (LTB) and a replacement, and cover any gap without buying blindly.
Terminology varies by manufacturer, but the usual lifecycle looks like this:
Two notice types are easy to confuse. A PCN (product/process change notification) describes a change to a part, such as a new fab site, material or package. It may or may not end a product. A PDN (product discontinuance notice) announces that a product will be withdrawn, and gives the final order and final shipment dates.
For reference, the industry standard on discontinuance notices, originally JEDEC JESD48 and now superseded by the joint J-STD-048A, has historically asked suppliers to allow at least six months from notice to place final orders and twelve months for final shipments. That is a minimum from a standard, not a promise. A supplier-specific policy or contract can differ, so the dates printed in your actual notice are the ones that count.
Before you commit any money, answer four questions from the manufacturer's own documentation:
Also rule out a typo. Some "obsolete" parts are simply a mistyped suffix or a missing packaging code.
Where to find notices, and how not to miss the next one. Check the PCN/PDN section on the manufacturer's website, subscribe to your authorized distributor's notifications and use the alerts for your part numbers in component lifecycle tools. Keep a list of critical parts and review their status every quarter. Hearing about an EOL from a middleman when the LTB window is already closing is the most expensive scenario.
An LTB order is one of the few moments in a component's life when you can buy with full manufacturer traceability, so it deserves a proper calculation, not a gut feeling.
Net LTB quantity ≈ forecast production until the end of the product's life + service, warranty and repair spares + yield and test loss + safety buffer − usable stock − confirmed inbound orders
Run at least two scenarios, a base case and a high-demand case, and write down the assumptions. Teams most often forget:
Then check the practical side:
A replacement search should run in parallel with the LTB, not after it. Alternatives come in three levels, and one cannot be swapped for another:
Start with the replacement recommended in the PDN, then use parametric search from manufacturers and distributors, cross-references and the datasheet itself. The word "equivalent" in a catalog is a reason to check the candidate, not permission to substitute it.
Bench-test the alternative on your actual board, not only in the datasheet. Then run a pilot build, update the BOM through an engineering change order, and obtain approvals from your quality team and, where required, your customer. Until then, forbid automatic substitutions in purchasing.
It happens: the notice was missed, the quantity was too low, or the LTB deadline passed during a design freeze. The remaining options are surplus and excess stock from other companies, and independent distributors.
Because these sources do not offer the same traceability as an authorized channel, apply risk-based controls:
| Situation | Usually best option |
|---|---|
| Long product life, small volume, replacement unclear | Larger LTB, plus a planned redesign |
| Drop-in replacement exists and is approved | Switch, plus a small LTB as insurance |
| Short remaining product life | LTB sized exactly to the plan |
| Replacement requires re-certification | LTB to bridge the time while you qualify it |
| Window closed, no replacement | Controlled secondary-market purchase with inspection |
We help customers source end-of-life and obsolete parts, and we buy back excess inventory. If you are looking for parts that are no longer in production, send us the part numbers and the quantities you need. If you have surplus stock that you no longer need, see our Sell Excess page.
It depends on the manufacturer's notice. Industry standards have historically set a minimum of six months from notice to final orders, but the date in your own notice governs. Always request it in writing from the manufacturer or your authorized distributor.
No. NRND means the part is still available but not advised for new designs. It often precedes discontinuance, so start looking at alternatives early, but you can usually still buy it.
Only as a candidate. A cross-reference tool matches headline parameters. You still need to compare the datasheets line by line, test on your own board and obtain approval before production.
It can be, if you treat it as a risk-managed purchase: request traceability, photos and date codes, define inspection requirements, and test according to the criticality of the application.
Full manufacturer part number with suffixes, quantity, acceptable date codes, packaging requirement, target price, delivery date, and any inspection or documentation requirements.
Send us the affected part numbers and quantities through our RFQ page, or upload your bill of materials on the BOM page, and we will reply with availability and a quote.
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