When a part on your BOM is reaching end of life or has disappeared into allocation, there are really only three ways forward: make a last-time buy of electronic components to cover the product’s remaining life, redesign the board around the problem part, or start a new design. Each one has a different cost, timeline and risk, and picking the wrong one is expensive in either direction.
At Thomas Instrumentation, we design boards, write the firmware that runs them and build them in production, so we see these decisions from all three sides. This post lays out the three paths plainly, what each one costs you, and the conditions that should point you toward one over the others as you plan 2027.
Why 2027 Sourcing Needs a Decision, Not a Reorder
In a normal market, a part on allocation eventually comes back. This time, some won’t. Memory makers are exiting DDR4 and MLC NAND on published timelines, and TrendForce reports that Murata will accept orders for certain general-purpose MLCCs only until 2028, with final shipments in 2029. The causes behind this are covered in our overview of chipflation and 2026 component price increases, and the memory specifics are in our post on DRAM and NAND allocation. What matters here is that “keep reordering and hope” has stopped being a plan.
Path 1: Last-Time Buy
A last-time buy means purchasing enough of a part to cover every unit you expect to build for the rest of the product’s life, usually in response to an end-of-life notice from the manufacturer.
What It Costs
The obvious cost is cash. You’re paying today, often at elevated prices, for parts you may not use for years. Less obvious are the carrying costs: storage, insurance, and controlled handling for moisture-sensitive parts that can’t sit on an open shelf. The biggest hidden cost is forecast error. Buy too few and you’re back where you started. Buy too many and you’ve paid for inventory you’ll eventually scrap.
How Fast It Works
When stock is available from authorized sources, a last-time buy is the fastest path by far. You place the order and the problem is covered. During allocation, though, suppliers may not grant the full quantity you request, and a last-time buy you can’t fill isn’t a solution.
When It’s the Right Call
- The product itself is within a few years of its own end of life.
- Demand is stable and well understood, so the quantity is a calculation rather than a guess.
- The part is still available from the manufacturer or authorized distribution.
- Requalifying a changed design would be expensive or slow, as it often is in medical and defense work.
Path 2: Redesign Around the Part
A redesign keeps the product and changes the board. You replace the affected part, or a small group of affected parts, with alternatives that are available and supported, then update the layout, firmware and test process to match.
Most discussion of shortages focuses on buying ahead. Redesign deserves more weight than it usually gets, because it’s the only path that turns a recurring supply problem into a one-time engineering cost.
What It Costs
The costs include engineering time for schematic and layout changes, firmware updates where the new part behaves differently, new fabrication and assembly setup, testing, and any regulatory or customer requalification the product requires. For a single-part change on a straightforward board, that can be modest. For a certified medical device, requalification can be the largest cost in the project.
How Fast It Works
A redesign is slower than a purchase order but faster than a new product. Timelines depend on how many parts change, how deeply they’re tied into the firmware, and what validation the product needs before it ships again.
What Else a Redesign Can Fix
A redesign done for availability is also a chance to address problems that have been sitting in the design for years. Engineers can move off memory that’s being discontinued, replace single-source parts with parts that have several qualified manufacturers, and remove capacity the product never actually needed. The product that comes out the other side is usually easier to source than the one that went in.
When It’s the Right Call
- The product has several years of shipments ahead of it.
- The trouble is concentrated in a handful of BOM lines rather than spread across the design.
- Available alternatives exist for the affected parts.
- The rest of the design, including the processor or microcontroller platform, is sound and supported.
Qualifying a substitute part has its own engineering steps, and we’ll cover those mechanics in a separate post. The decision to redesign comes first.
Path 3: Start a New Design
Sometimes the problem part is a symptom. If the microcontroller platform itself is being retired, several memory and passive lines are affected at once, or the product was already due for a refresh, patching the current board can cost almost as much as replacing it.
What It Costs and How Long It Takes
A new design carries the highest upfront cost and the longest timeline of the three paths. It includes full development, prototyping, validation and certification. In exchange, it gives you the longest runway: a product built around parts that are current today, chosen with availability in mind from the first schematic.
When It’s the Right Call
- The core platform, not just a peripheral part, is at or near end of life.
- Multiple lines across the BOM are affected at the same time.
- Customers are already asking for features the current design can’t support.
- A refresh was on the roadmap anyway, and the shortage simply moves it up.
Comparing the Three Paths
| Path | Upfront cost | Time to resolve | Main risk | Best fit |
|---|---|---|---|---|
| Last-time buy | Inventory cash and carrying costs | Fastest, if stock is available | Forecast error and allocation limits | Products near their own end of life with stable demand |
| Redesign | Engineering, testing and requalification | Moderate | Introducing change into a proven product | Products with years of life left and a few problem parts |
| New design | Full development and certification | Longest | New-product risk and schedule | Products whose platform is aging or already due for a refresh |
Five Questions That Point to the Right Path
- How many more years will this product ship? Short remaining life favors a last-time buy. Long remaining life favors redesign.
- How many BOM lines are at risk? One or two points toward redesign. Many points toward a new design.
- What does requalification cost in your industry? The higher it is, the more a last-time buy is worth.
- Can you fund the inventory? A last-time buy ties up cash for the life of the product.
- Was a refresh already planned? If so, the shortage may simply be telling you to start it now.
Many Products Need Two Paths at Once
In practice, the best plan is often a combination. A bridge buy covers production for as long as the redesign or new design takes to reach the line, so shipments never stop while engineering does its work. The key is sizing that bridge to a realistic engineering schedule, not an optimistic one. This is where having design and manufacturing in the same building matters, because the people estimating the redesign are sitting next to the people who’ll build the board.
How Thomas Instrumentation Helps With All Three
We can source quality parts for a last-time buy through our supply chain team, redesign an affected board through our PCB design and layout services, update the firmware through our embedded software development group, and take a new design from concept to production. Customers have noticed the advantage. As Brian Canna of Boekel Scientific put it, “Since they also manufacture it really helps with sourcing the components.”
For customers in regulated markets, including medical and healthcare technology, we factor requalification into the recommendation from the start, because that’s often what decides which path makes sense. You can see the full range of our electronics services on our site.
Frequently Asked Questions About Last-Time Buys and Redesigns
What is a last-time buy for electronic components?
A last-time buy is a final purchase of a component, sized to cover all remaining production of a product, typically made after the manufacturer issues an end-of-life notice. It trades upfront cash and storage costs for supply certainty.
When should you redesign instead of buying ahead?
Redesign usually makes more sense when a product has several years of shipments left, the supply problem is limited to a few parts, and suitable alternatives are available. It solves the problem permanently instead of postponing it.
How long does a PCB redesign for an obsolete component take?
It depends on how many parts change, whether firmware needs updating, and what testing or certification the product requires. A single-part change on a simple board moves much faster than a change to a certified medical or defense product.
Can a last-time buy and a redesign be combined?
Yes, and they often should be. A smaller bridge buy keeps production running while the redesign is completed and qualified, which avoids both a line-down and an oversized final purchase.
Decide Before the Market Decides for You
If you have parts on your BOM with end-of-life notices, thin allocation or no clear 2027 supply, we’ll help you work out which path fits each product and what it will realistically cost. Talk with our engineering and sourcing team about your BOM.
