STMicroelectronics
0
Often, teams only realize there is a risk when a buyer cannot place an order, an EOL notice arrives, or a customer's delivery date is already set. At that point, it is too late for prevention. The focus shifts to addressing costly inventory, emergency sourcing, untested alternatives, or even redesigning the PCB.
A solid BOM review should leave you with a practical working list, not just a presentation.
Use these columns in your spreadsheet, PLM, ERP, or BOM-management system:
| BOM revision | The exact BOM and product revision being reviewed |
| Reference designator | Where the component is used |
| Manufacturer and MPN | Exact approved manufacturer part number |
| Quantity per assembly | Units required in one finished product |
| Lifecycle status | Active, NRND, EOL, last-time-buy, unknown |
| Supply status | Confirmed, long lead time, allocated, unavailable, unknown |
| Approved alternate | Exact alternate MPN and approval status |
| Technical recovery level | Exact substitute, form-fit-function alternate, redesign, none |
| Quality/traceability status | Authorized, approved independent, open-market only, incomplete |
| Risk score | Green, yellow, orange, or red |
| Production impact | Number of builds or customer orders exposed |
| Mitigation action | Buy, qualify, redesign, validate, monitor, or escalate |
| Owner | Named person—not a department |
| Due date | The date before production is affected |
| Evidence | Datasheet, PCN, supplier quote, lifecycle notice, approval record |
| Next review date | When the risk must be checked again |
A BOM risk assessment is a step-by-step review of every component in a product to spot anything that could stop it from being built, shipped, serviced, or supported.
A lifecycle database might list a part as active, which is helpful, but it does not tell you if the part is safe for your next build or for the next five years of production.
| Active, but one manufacturer | A single supplier can create a production stop | Identify and qualify a second source or approved alternate |
| Active, but allocated | The supplier may control quantities or prioritize larger customers | Obtain confirmed supply and assess build exposure |
| Active, but long lead time | The part may arrive after the required production date | Compare confirmed delivery with your actual build schedule |
| Active, but no alternate | Any change may require redesign or requalification | Start alternate research before a crisis |
| Active, but old process/package | The part may have elevated lifecycle or support risk | Monitor manufacturer notices and identify a migration path |
| Active, but open-market-only | Quality and traceability risk may be unacceptable | Define supplier, documentation, and inspection requirements |
| Active, but sole-region production | A local disruption can affect the global supply path | Map manufacturing and logistics concentration where possible |
A manufacturer acquisition, merger, or product-line consolidation should also trigger a review. It does not automatically mean a part will become obsolete, but it can change product priorities, channels, support, or lifecycle plans.
[ ext{Required quantity} = ext{quantity per assembly} imes ext{planned build quantity} imes (1 + ext{yield allowance}) ]
“Confirmed usable supply” should not include inventory that is unapproved, untraceable, set aside for another program, outside date-code requirements, or arrives too late for your build.
Not every cross-reference is an alternate.
Classify each high-risk part by the recovery effort required:
| Exact substitute | Same approved MPN or manufacturer-approved replacement | Low |
| Form-fit-function alternate | Different manufacturer, but electrical and mechanical requirements are met | Medium |
| Pin-compatible alternate | Similar pinout and function, but requires design validation | Medium to high |
| Design variant | Package, firmware, PCB, thermal, or circuit changes required | High |
| No viable alternate | Proprietary, calibrated, safety-critical, or unique part | Critical |
A distributor might suggest a replacement, but it becomes usable only after engineering approves it.
The 2021 shortage showed why low inventory and concentrated supply can create outsized disruption. The U.S. Department of Commerce reported that, among responding companies, median inventory for the hardest-to-source semiconductor products fell from 40 days in 2019 to fewer than 5 days in 2021. U.S. Department of Commerce findings
When an active part becomes allocated or obsolete, buyers may need to look outside authorized channels. That can be a legitimate recovery path, but it requires stronger controls.
Inspection is not a one-size-fits-all service. Visual checks, marking reviews, X-rays, decapsulation, electrical testing, and third-party analysis each catch different risks. The right level of control depends on the part, the application's criticality, the evidence you have, and what could happen if it fails.
AI infrastructure, data centers, automotive electronics, telecom, and industrial automation can all drive up demand for certain types of components. The right response is not to panic and buy everything in sight.
A risk score should help you see your priorities clearly. It should not be used to hide tough decisions.
Use a 0-to-5 score for each risk dimension, then apply weights based on your product type.
| Lifecycle | 25% | EOL, past last-time-buy, or unknown lifecycle |
| Availability | 25% | No confirmed supply, allocation, or build-stopping lead time |
| Technical recovery | 20% | No qualified alternate; redesign required |
| Quality/traceability | 15% | Open-market-only source with incomplete evidence |
| Geographic concentration | 10% | One critical region or manufacturing path |
| Compliance/qualification | 5% | Required approval or documentation missing |
( ext{Risk score} = sum( ext{risk score} imes ext{weight}))
Use the final score to set an action level:
| Green | Data complete; no material issue identified | Monitor on normal review cycle |
| Yellow | Warning condition; recovery path exists | Validate supply or alternate and assign an owner |
| Orange | Meaningful cost, schedule, or production exposure | Escalate to engineering, procurement, and quality |
| Red | Production-stopping, compliance-critical, or no recovery path | Immediate action plan and management review |
Even a perfect analysis is useless if it is done on the wrong BOM revision.
Flag ambiguous part numbers immediately. One missing suffix can change voltage, temperature, package, tape format, tolerance, or qualification.
At this stage, classify all EOL, NRND, unknown, single-source, or no-alternate lines as review candidates.
Ask the buyer to confirm—not estimate—the supply path.
A part with a 30-week lead time might be low risk for a design concept, but it is a red flag if your build is scheduled in eight weeks.
A cheap resistor with several approved sources is usually less urgent than a single-source power-management IC that has no pin-compatible alternative.
Use one shared risk register.
| Hardware engineer | Technical requirements, circuit validation, firmware impact |
| Component engineer | Lifecycle, package, qualification, alternates |
| Procurement | Quotes, supply confirmation, MOQ, lead time, supplier options |
| Supply-chain manager | Forecast, inventory policy, escalation, risk acceptance |
| Quality engineer | Supplier approval, traceability, inspection, documentation |
| Manufacturing/EMS | Assembly impact, yield, process, build schedule |
| Program manager | Cost, timing, customer communication, final tradeoffs |
Do not let a quick purchasing fix turn into an unapproved engineering change. Also, make sure that even technically valid alternates go through quality approval.
This is the stage where your BOM health review actually becomes useful for operations.
Tools can reduce the time needed to find lifecycle, availability, and compliance issues.
| SiliconExpert or similar intelligence platforms | Lifecycle, PCNs, compliance, alternates, supply data | Part approval and application-specific suitability |
| Altium BOM Portal | Lifecycle, compliance, alternate coverage, supply-chain dashboard | Revision control, AVL rules, engineering sign-off |
| Octopart BOM Tool | Distributor inventory, lead time, pricing, datasheets, sourcing discovery | Confirmed allocation and technical substitution |
| PLM/ERP systems | BOM revision, AVL, inventory, POs, approvals | Data maintenance and cross-functional discipline |
| Manufacturer notices | Official lifecycle, datasheet, PCN, qualification information | Actual customer allocation and final sourcing availability |
1. Reviewing the BOM only after a shortage
Risk assessment should happen before PCB release, before a production build, after lifecycle notices, and on a defined recurring schedule.
2. Scoring risk without assigning actions
A red score does not fix a part. Every redline needs an owner, a deadline, and a recovery path.
3. Treating visible stock as confirmed supply
Online inventory might be outdated, already reserved, unapproved, or not able to meet your date-code and delivery needs.
4. Calling every similar part an equivalent
A technically similar part may fail package, firmware, qualification, reliability, or loop-stability requirements.
5. Buying inventory before calculating lifetime demand
A last-time-buy can help you avoid a production stop, but buying too much can leave you with expired, obsolete, damaged, or stranded inventory. Always calculate demand, yield, service needs, storage conditions, and alternate timing before making a decision.
How often should a BOM risk assessment be performed?
Perform one before PCB release, before major production builds, after PCN or lifecycle notices, and on a recurring schedule for active products. Quarterly is a practical baseline for many programs; high-risk or fast-changing products may require monthly review.
What is the highest-risk BOM component?
Usually, it is a production-stopping part with no approved alternate. Examples can include a proprietary IC, FPGA, power-management controller, calibrated sensor, custom connector, or qualified automotive device.
Is an active component low risk?
No. An active component can still have allocation, long lead time, single-source, geographic, quality, or alternate-approval risk.
Can an independent distributor help reduce BOM risk?
A qualified independent distributor can help locate active, obsolete, or hard-to-source components when authorized supply is unavailable. The buyer should still verify supplier qualification, traceability, part condition, documentation, and required quality controls.
What is the minimum output of a BOM risk assessment?
At minimum: an exact MPN list, lifecycle and supply status, approved alternate coverage, risk level, production impact, mitigation action, named owner, due date, and evidence source.
Need a BOM sourcing review?
WELL LINK CHIPS GROUP CO.,LIMITED FLAT/RM 1802 BEVERLY HOUSE 93-107 LOCKHART ROAD WANCHAI HK
