Ready Stock Datasheet Coverage: 995 of 1,125 Hong Kong Part Numbers Sit in a Series With a Walsin Approval Sheet, Against 15.8% of the Catalogue

Ready stock datasheet coverage is 88.4 percent: 995 of the 1,125 part numbers on our Hong Kong shelf sit in a series or type that a Walsin approval sheet we hold describes. Across Walsin’s 359,135-part catalogue the rate is 15.8 percent. The shelf is documented 5.6 times more densely than the range it was picked from.

Ask a distributor for the datasheet behind a stocked part and most cannot say which one it is. Venatech Limited, an authorised Walsin distributor in Hong Kong, holds 28 datasheets from Walsin Technology (Walsin), 451 pages, and 84.2 percent of the catalogue falls outside them. We wanted to know whether the shelf does too. We took the ready-stock snapshot of 23 September 2026, matched every line to Walsin’s parametric exports with spaces removed, assigned each matched line to its series, and tested the series against the 28 sheets. Every part number below is real and every figure is a part-number count.

How many ready-stock part numbers sit in a series with a datasheet we hold?

995 of 1,125, or 88.4 percent. We classified every line. 764 ceramic lines sit in nine MLCC series that each have a Walsin sheet, 231 resistor lines carry a WR12, WR08, WR06 or WR04 prefix that the WR approval sheet names, 22 matched lines have no sheet, and 108 have no export row so we cannot assign them. Even if all 108 are undocumented, the shelf holds 88.4 percent.

One of the 231 resistor lines, WR12X0000FTL, has no export row and is counted by its prefix alone. Without it the count is 994 of the 1,016 lines that carry an export row, 97.8 percent. The chip resistor label also hides four lines that do not join, including one varistor code, which is why 254 splits 231, 19 and 4.

Which nine MLCC series carry the 764 ceramic lines, and which sheet covers each?

Nine of Walsin’s 16 exported MLCC series, and the General Purpose series alone carries 490. We joined each stocked code to its series file and read the series name Walsin prints. Every one of the nine has a sheet in our set of 28, together 135 pages. Add the 10-page WR sheet and ten sheets, 145 of our 451 pages, document 995 shelf lines.

The ceramic shelf is documented almost by construction: 764 of the 764 lines that join an MLCC row sit in a series with a sheet. We saw why when we looked at what is missing. Walsin’s MLCC export has no row for six series that do have sheets, so no shelf line can land in them. For the series list behind this, see which Walsin MLCC series are on the shelf.

How does the shelf compare with the catalogue?

The catalogue is 15.8 percent documented and the shelf is 88.4. We counted 56,827 distinct part numbers, out of 359,135, in a series or type that one of our sheets describes. 23,601 are MLCC, 19,660 carry a WR04, WR06, WR08 or WR12 prefix and 13,566 carry an MR prefix; the MR automotive sheet we hold names MR04, MR06, MR08, MR10 and MR12. The shelf holds 0 MR lines.

We have not seen this counted anywhere: the documentation rate of a distributor’s own shelf, set beside the documentation rate of the range it draws from. 88.4 against 15.8 is the number. A buyer who is asked “do you have the datasheet?” for a stocked part can usually say yes. For a catalogue part the odds are one in six. The WR family is mapped in the Walsin general purpose chip resistor range.

Which 22 matched stock lines have no sheet at all?

Six WR codes at two sizes, five anti-surge, five high-precision, three current-sense, two inductors and one array. We listed every matched line outside the 995. The 22 break down as WR02 (4) and WR25 (2), MF12 (5), WF (5), WW (3), WLPH (2) and WA (1). None has a sheet in the 28.

The shelf is documented where the sheets are, which is the ceramics and one resistor family. Where Walsin’s sheets stop, so does our paper. Thin film, inductor, varistor, disc, RF and antenna lines have no datasheet in our set, so for those we send the export row and flag every figure.

What does series coverage not prove?

Three things. A sheet describes a series, not a code, so “the series has a sheet” does not mean “this code appears in a table in it”. The WR sheet is ASC_WR_V24, SEP 2016, and the MR sheet is ASC_MR_V13, March 2024: dates a buyer should read before a submission. And 108 of 1,125 lines, 9.6 percent, have no export row, so even the series is unknown. Those 108 plus WR12X0000FTL are the 109 codes Walsin’s exports do not return, and 101 of the 109 sit in one internal register; the story is in why one register explains 101 of 109 gaps.

A datasheet is also not a qualification report. Document types such as PPAP, IMDS and a Declaration of Conformity appear nowhere in the 451 pages we hold. We say so because the sentence “we have the datasheet” is true of 995 shelf lines and does not answer the question an automotive auditor is actually asking.

What should a supplier-approval file ask for on a stocked line?

Ask for the sheet by series, then the revision, then what is not in it. For any stocked code the answer begins on the ready stock page, which lists 1,125 part numbers as at 23 September 2026, a dated snapshot and not a live feed. Cross your incumbent with the free cross-reference tool, take the Walsin code it returns, and ask us for the sheet that covers it. The ceramic range sits on the MLCC page.

For AVL work, put the lot and date-code traceability, certificate of conformity per shipment on request and original sealed Walsin packaging in the file, and put the gaps in beside them. Our fuller list of what we hold is in AVL submission documentation: what we hold. We will tell you what we do not have. Nobody else will.

The short version

We matched 1,125 stocked lines to Walsin’s exports and tested the series against 28 sheets. 995 lines, 88.4 percent, sit in a documented series, on ten sheets and 145 pages. The catalogue is 15.8 percent. 22 matched lines have no sheet, 108 have no export row, and 0 of 13,566 MR parts are on the shelf. A sheet describes a series, not a code, and the WR sheet is dated September 2016. We will not tell you a stocked part is qualified. We will tell you which document describes it. Confirm against the sheet and qualify in your own circuit.

Send us the part numbers on your approved vendor list and we will return the sheet that covers each one, and the ones with none. And a question back: of the parts on your AVL, what share has a datasheet revision you have actually read?

Frequently asked questions