Walsin shelf life is 12 months on the capacitor sheets and two years on the resistor sheets, and the clock starts at three different events. We read the storage clause on all 28 datasheets we hold: 25 count from shipment, one from receipt, two from an undefined “operation date”, and 4 sheets state no MSL level.
Venatech Limited, an authorised Walsin distributor in Hong Kong, holds 28 Walsin Technology (Walsin) datasheets, 451 pages. A goods-in team in Slovakia that stamps a use-by date on a reel has to choose a start date, and the datasheets do not agree on one. We extracted the text of every page and read the storage clause on each sheet. Every part number below is real and checked against our master set. We will not tell you a shelf life is the same across two lines. We will show you where the sheets differ.
How many Walsin datasheets state a use-by period, and when does the clock start?
All 28 state one, and they start the clock three ways. 25 sheets count from shipment, one counts from receipt and two count from an “operation date”. The period is written “one year” on 19 sheets, “12 months” on 7 and “two years” on 2. We counted each phrase on each sheet.
| Wording on the sheet | Sheets, of 28 | Which sheets | Example part | Match / mismatch against a clock that starts at shipment |
|---|---|---|---|---|
| “used within one year after shipment” | 19 | 18 capacitor series sheets and the catalogue | 0603B104K500, SG18B102K500 |
reference |
| “used within 12 months after shipment and checked the solderability” | 6 | Large Size, three safety sheets, both Mega Cap sheets | 1825B102K302 |
Match on start, mismatch on wording |
| “used within 12 months upon receipt” | 1 | the MLCC application guide | none | Mismatch — the clock starts at your dock, not Walsin’s |
| “used up within two years since operation date” | 2 | the WR and MR resistor sheets | WR06X1002FTL, MR06X1002FTL |
Mismatch — a different start and double the period |
We have not seen this counted anywhere: 28 sheets, one storage window, and three different answers to the question “twelve months from what?”.
Do the storage temperature and humidity limits differ between Walsin sheets?
No, and that is the point. All 28 sheets give the same window: 5 to 40 °C and 20 to 70 percent relative humidity. We searched every sheet for it and found it on every one, the Feed-Through sheet twice. Only the clock and the caveats around it move.
| Storage field | Capacitor series sheets (24) | Application guide and catalogue (2) | Resistor sheets (2) | Match / mismatch |
|---|---|---|---|---|
| Temperature | 5 to 40 | 5 to 40 | 5 to 40 | Match on all 28 |
| Relative humidity | 20 to 70 percent | 20 to 70 percent | 20 to 70 percent | Match on all 28 |
| Clock starts at | shipment | receipt (guide), shipment (catalogue) | “operation date” | Mismatch |
| Period | one year or 12 months | 12 months or one year | two years | Mismatch |
| Test atmosphere humidity (“room condition”) | 25 to 75 percent on 23 of 24 | 25 to 75 percent in the catalogue | 45 to 75 percent | Mismatch — 25 against 45 at the lower bound |
One capacitor sheet defines no test atmosphere at all: 17_Safety_X1Y2_Automotive_S2_H.pdf carries no “room condition” line. The application guide is covered in our MLCC shelf-life checklist; that post quotes the guide’s 12 months upon receipt, which is the one sheet of 28 that starts the clock at your dock.
Is a Walsin resistor shelf life really twice a Walsin capacitor shelf life?
On paper, yes. Both resistor sheets say “two years since operation date as ensured shelf life”. The 24 capacitor series sheets say one year or 12 months. Twenty-four months against 12. Both resistor sheets repeat the clause word for word, and both tell you to check solderability if you need an extension.
The term “operation date” is not defined on either resistor sheet. The WR sheet is ASC_WR_V24, dated September 2016, and the MR sheet is ASC_MR_V13, dated March 2024; the same clause sits in both, issued seven and a half years apart. Walsin’s capacitor sheets say “shipment”, which a goods-in team can check against a delivery note. A resistor “operation date” cannot be checked against anything we hold.
Which Walsin sheets state no MSL level?
Four of 28. 24 sheets state “MSL Level 1”: 23 capacitor series sheets and the catalogue. The application guide, the Large Size sheet and both resistor sheets state none. We searched every page for the string.
| Sheet | Pages | MSL Level 1 stated | Example part | Match / mismatch against the other capacitor sheets |
|---|---|---|---|---|
| 23 of 24 capacitor series sheets | 8 to 29 each | yes | 0603B104K500, S242B101K502 |
reference |
03_Large_Size_1825_2220_2225.pdf |
10 | no | 1825B102K302 |
Mismatch — the only capacitor series sheet without it |
00_MLCC_Application_Guide.pdf |
12 | no | none | Mismatch — a mounting guide |
Walsin_WR_General_Purpose_Chip_Resistor.pdf |
10 | no | WR06X1002FTL |
Mismatch — resistor sheet, no moisture level |
Walsin_MR_Automotive_Thick_Film_Chip_Resistor.pdf |
10 | no | MR06X1002FTL |
Mismatch — resistor sheet, no moisture level |
The Large Size sheet is the one to notice. The soft-termination sheets for 1808 to 2225 and the safety sheets for 1808 to 2220 all state MSL Level 1; the sheet that covers 1825, 2220 and 2225 alone does not. It carries the same storage window and the same 12-month clause as them, and the MSL string is missing. The sheet’s data is Walsin’s; whether the omission means anything is Walsin’s to say.
Why do six capacitor sheets list different corrosive gases from the other eighteen?
Because they are a different template. 18 capacitor series sheets say “Storage and handling conditions” and list hydrogen sulfide, sulfur dioxide, chlorine and ammonia. Six say “Storage”, list sulfuric acid, ammonia, hydrogen sulfide and chlorine, and drop the silver-migration warning. The six are exactly the sheets that say “12 months after shipment”.
| Item | 18-sheet template | 6-sheet template | Resistor sheets | Match / mismatch |
|---|---|---|---|---|
| Heading | Storage and handling conditions | Storage / Application notes | Storage and Handling Conditions | Mismatch |
| Period wording | one year | 12 months | two years | Mismatch |
| Gases named | hydrogen sulfide, sulfur dioxide, chlorine, ammonia | sulfuric acid, ammonia, hydrogen sulfide, chlorine | sulfide, chloride gas, acid | Mismatch — three lists |
| Silver migration warning | yes | no | no | Mismatch |
| Dew and direct sunlight warning | yes | taped product out of sunlight only | sunlight, shock, vibration | Mismatch |
The six-sheet template belongs to the high-voltage and safety lines. Whether silver migration is irrelevant there or simply unmentioned is not in the documents we hold. We report the omission and do not interpret it.
What should a Slovak incoming-inspection team record when a Walsin reel arrives?
The clause, the start event and the sheet. For a capacitor, count 12 months from shipment, not from your own receipt, unless you hold the application guide as your governing document. Three records remove the ambiguity this post counted.
- Record which sheet governs the part and its footer date. 25 of 28 start at shipment; one starts at receipt; two start at an undefined date.
- Print the period as the sheet writes it. One year and 12 months are the same length, but the resistor two years is not.
- Check solderability before you extend. 27 of 28 sheets say so; the application guide is the one that does not.
We hold 28 datasheets, 451 pages, and send the one covering your part number on request. We hold none for thin film, inductor, varistor, disc capacitor, RF or antenna parts, so a shelf life for those lines must come from Walsin directly. What is in Hong Kong is on ready stock — 1,125 part numbers as at 23 September 2026, a dated snapshot and not a live feed; ask us the date code of a line before you plan a clock around it. For the date-code ages of the lines on our shelf see MLCC date code age. To cross a part first, use the free cross-reference tool. The capacitor range sits on the MLCC page.
The short version
All 28 sheets state the same storage window, 5 to 40 °C and 20 to 70 percent, and a use-by period. The clock starts at shipment on 25 sheets, at receipt on one and at an undefined “operation date” on two. The period is one year on 19 sheets, 12 months on 7 and two years on 2. 24 sheets state MSL Level 1 and 4 do not, among them the Large Size sheet. Six capacitor sheets use a different storage template with a different gas list and no silver-migration warning. Confirm against both datasheets and qualify in your own process.
Send us the part number and the shipment date on your delivery note, and we will name the sheet and the clock that govern it. And a question back: which date does your goods-in system print on the reel, and who decided?
Frequently asked questions
How long is the shelf life of a Walsin MLCC?
Twelve months on every capacitor sheet we hold. Eighteen series sheets and the catalogue write it as one year after shipment, six series sheets write 12 months after shipment, and the application guide writes 12 months upon receipt. The storage window is 5 to 40 degrees Celsius and 20 to 70 percent relative humidity.
How long is the shelf life of a Walsin chip resistor?
Two years, on both resistor datasheets we hold, the WR and MR series. The clause reads two years since operation date as ensured shelf life, with solderability to be checked if an extension is needed. Walsin does not define operation date on either sheet, so confirm the start of the clock with Walsin.
Does the Walsin shelf-life clock start at shipment or at receipt?
At shipment on 25 of the 28 sheets we hold, at receipt on the application guide alone, and at an undefined operation date on the two resistor sheets. If your governing document is a series sheet, a Slovak goods-in team should count from the shipment date on the delivery note, not from its own receipt date.
Do all Walsin datasheets state an MSL level?
No. Twenty-four state MSL Level 1: 23 capacitor series sheets and the catalogue. The application guide, the Large Size 1825, 2220 and 2225 sheet and both resistor sheets state none. Ask Walsin for the moisture sensitivity level of the exact part number if your process needs it in writing.
Do the storage temperature and humidity limits differ between Walsin sheets?
No. All 28 sheets state 5 to 40 degrees Celsius and 20 to 70 percent relative humidity. Only the start of the clock, the period, the MSL statement and the list of corrosive gases differ. The test atmosphere humidity also differs, at 25 to 75 percent on capacitor sheets and 45 to 75 percent on resistor sheets.
Can you tell me the shelf life of a Walsin inductor or varistor?
No. We hold no datasheet for inductor, varistor, disc capacitor, RF, antenna or thin film parts, so we hold no Walsin storage clause for them. We will tell you so rather than apply a capacitor or resistor figure to a different product line. Ask for a written statement from Walsin.