Venatech holds two data sets for Walsin thin film resistor part numbers, and they differ by a factor of 12.4. We counted 1,168,998 distinct part numbers in six upload files and 93,914 in the parametric export. The export is 8.0 percent of them, and three of the six series have no export row at all.
Venatech Limited, an authorised Walsin distributor in Hong Kong, has published thin film counts built on the 93,914-row export from Walsin Technology (Walsin). This post is written from that export, the 20 thin film files behind it, and six upload files built on 19 September 2026. Every part number below is real and is in the export. We opened the upload files, joined them on part number, and found that the number we have been quoting is a subset, not the catalogue.
How many Walsin thin film part numbers do our two data sets hold?
1,168,998 in the upload files and 93,914 in the export, and the export sits wholly inside the upload. We read the part-number column of all six upload files, 1,168,998 rows with no duplicate, and of the 11 export files that hold rows. All 93,914 export part numbers are in the upload; 1,075,084 upload part numbers are not in the export. The export is 8.03 percent of the upload.
| Upload series | Upload part numbers | In the export | Export share | Match / mismatch |
|---|---|---|---|---|
| WF, precision | 373,848 | 58,314 | 15.6% | Mismatch: 84.4% not in the export |
| WF.Q, AEC-Q200 | 230,973 | 0 | 0% | Mismatch: no export row |
| SF.Q, anti-sulfuration, AEC-Q200 | 230,845 | 0 | 0% | Mismatch: no export row |
| SF.A, anti-sulfuration | 176,170 | 0 | 0% | Mismatch: no export row |
| SF, anti-sulfuration | 91,602 | 15,080 | 16.5% | Mismatch: 83.5% not in the export |
| MF, tantalum nitride | 65,560 | 20,520 | 31.3% | Mismatch: 68.7% not in the export |
| All six | 1,168,998 | 93,914 | 8.0% | Mismatch |
We have not seen this counted anywhere. The thin film count in the earlier posts on this site is the export figure, and it is correct as a count of the export. It was never a count of the thin film catalogue, and on 19 September 2026 the upload files already held 12.4 times as many. The scale of Walsin’s own thin film matrix is covered in what is actually in Walsin’s thin film catalogue.
Which thin film series have no row in the export at all?
Three: WF.Q, SF.Q and SF.A. Together they hold 637,988 part numbers, 54.6 percent of the upload. We grouped every upload row by series and tested each part number against the export. None of the 637,988 is in it. That includes both series labelled AEC-Q200, WF.Q and SF.Q, with 461,818 part numbers between them.
The export is the set behind the nine thin film export files that return nothing, and the AEC-Q200 and SF.A files are among those nine. The upload files cover the series those nine files do not. AEC-Q200 appears in the series label in our upload files, and Walsin’s wording for the standard is compliant, not certified. Ask for the qualification report for the exact part number. Venatech makes no qualification claim of its own. The upload part numbers are not on our master list of cited parts, so this post names none of them.
Which tolerances of the WF series does the export hold?
One in full, one block more, and none of three. The WF export has 58,314 rows. All 52,808 WF parts at plus or minus 0.01 percent are in it, with the T suffix before the packing code. It holds no WF part at plus or minus 0.02, 0.05 or 0.25 percent, where the upload has 52,821, 52,831 and 52,833.
| WF tolerance | Upload part numbers | In the export | Real part in the export | Match / mismatch |
|---|---|---|---|---|
| ±0.01% | 52,808 | 52,808 | WF10T27R0TTL |
Match: all in the export |
| ±0.02% | 52,821 | 0 | none | Mismatch: none in the export |
| ±0.05% | 52,831 | 0 | none | Mismatch |
| ±0.1% | 54,505 | 1,674 | WF02T1000BTL (0201) |
Mismatch: 3.1% |
| ±0.25% | 52,833 | 0 | none | Mismatch |
| ±0.5% | 54,169 | 1,916 | WF02Q27R0DTL (0201) |
Mismatch: 3.5% |
| ±1% | 53,881 | 1,916 | WF02Q27R0FTL (0201) |
Mismatch: 3.6% |
The 1,674, 1,916 and 1,916 are one block: the 5,506 WF parts at 0201, which are in the export in full. Every other WF case size is in the export only at plus or minus 0.01 percent. A selector built on the export therefore finds the tightest tolerance in the file and almost nothing between it and 1 percent outside 0201. The earlier statement in this series that thin film reaches plus or minus 0.01 percent on 52,808 rows is true of the export, and is in the tolerance notation post.
Which case sizes does the export hold for the MF and SF series?
Whole sizes, or none of them. We cross-tabulated size against presence in the export for each series. MF is in the export at 1206 only: 20,520 of 20,520, and 0 of the 45,040 at 0402, 0603 and 0805. SF is in the export at 1206 and 2010 only: 270 and 14,810 of the same, and 0 of the 76,522 at the other five sizes.
| Series and size | Upload part numbers | In the export | Real part in the export | Match / mismatch |
|---|---|---|---|---|
| MF 1206 | 20,520 | 20,520 | MF12Q9421FTL |
Match |
| MF 0402, 0603, 0805 | 45,040 | 0 | none | Mismatch |
| SF 2010 | 14,810 | 14,810 | SF20T25R2BTL |
Match |
| SF 1206 | 270 | 270 | SF12T1R00ATL |
Match |
| SF 0402, 0603, 0805, 1210, 2512 | 76,522 | 0 | none | Mismatch |
| WF 0201 | 5,506 | 5,506 | WF02Q27R4DTL |
Match |
| WF 0402 to 2512 | 368,342 | 52,808 | WF20F6803TTL |
Mismatch: 14.3% |
The pattern follows the export’s files. Its 20 thin film files are per-size or per-series downloads, nine return no rows, and the WF files for 0402 to 2512 hold only the 0.01 percent rows. A part at 2512 in the SF series, 35,092 part numbers in the upload, does not exist for any search built on the export. See thin film versus thick film chip resistors for what is at stake in choosing between the two.
Do the 93,914 rows that appear in both files agree?
On every field. We merged the two on part number and compared seven shared fields: size, resistance, tolerance, TCR, rated power, packaging and termination. The 93,914 rows differ in 0 cells in all seven. The only difference is the wording of the series label, which differs on all 93,914: “WF (Precision)” in the upload, “Thin Film Precision Chip Resistor /WF Series” in the export.
That is the useful half of the finding. Where the two files overlap they are the same data, so the upload is a faithful extension of the export and not a competing source. A series label is not a join key: filtering on the export’s long label returns none of the upload’s rows, and the reverse. Join on part number.
What should a thin film search or cross-reference do with this?
Treat the 93,914 as a sample with a known shape, and say so. A tolerance filter on the export returns the 0.01 percent parts and the 0201 parts and nothing else in the WF series. A size filter returns three sizes for MF and SF at most. Every thin film part we show you by name in this post is in the export; for the other 1,075,084, the part number exists in our upload and no Walsin document we hold covers it.
We hold 28 Walsin datasheets, 451 pages, and none for thin film, so the datasheet links inside the upload files, which point to Walsin’s own PDFs, have not been opened by us. The free cross-reference tool matches against Walsin’s published catalogue and states differences from your original. Ready stock in Hong Kong is a dated snapshot, 1,125 part numbers as at 23 September 2026, and is on ready stock. The thin film range sits on the thin film page. Confirm against both datasheets and qualify in your own circuit.
The short version
We counted thin film twice. The six upload files hold 1,168,998 distinct part numbers and the export 93,914, 8.0 percent, wholly inside the upload. WF.Q, SF.Q and SF.A, 637,988 part numbers between them, have no export row. The WF export holds all 52,808 parts at plus or minus 0.01 percent and none at 0.02, 0.05 or 0.25 percent; MF is in the export at one size of four and SF at two of seven. Where the files overlap they agree on 7 of 7 fields. We will not tell you a thin film part is available because a search found it. We will tell you which file it came from. Qualification stays with you.
Send us a thin film requirement, with tolerance and case size, and we will tell you whether the part is in the export, only in the upload, or in neither. And a question back: if your cross-reference tool says there is no 0.05 percent Walsin part, how would you know it had looked at the whole catalogue?
Frequently asked questions
How many Walsin thin film part numbers does Venatech hold?
The six thin film upload files hold 1,168,998 distinct part numbers, and the parametric export holds 93,914. The export is 8.03 percent of the upload and sits wholly inside it. We re-counted the upload files and they match the README beside them, but we have not re-queried Walsin and hold no thin film datasheet.
Which Walsin thin film series are missing from the export?
Three: WF.Q, SF.Q and SF.A, with 230,973, 230,845 and 176,170 part numbers in the upload and none in the export. Two of them carry an AEC-Q200 label on the series name. Walsin describes AEC-Q200 as compliant, not certified, so ask for the qualification report for the exact part number.
Why does my search for a 0.05 percent Walsin thin film resistor return nothing?
Because the export holds no WF part at plus or minus 0.02, 0.05 or 0.25 percent, while the upload has 52,821, 52,831 and 52,833 of them. The export holds every plus or minus 0.01 percent WF part, 52,808, and a block of 5,506 at 0201. A search on the export alone cannot see the rest.
Which thin film case sizes are in the export?
All of WF at 0201 and WF at plus or minus 0.01 percent from 0402 to 2512; MF at 1206 only; SF at 1206 and 2010 only. Of the 65,560 MF part numbers in the upload, 45,040 at 0402, 0603 and 0805 are not in the export. Of 91,602 SF, 76,522 at five sizes are not.
Do the two thin film files disagree on any specification?
No. We merged them on part number and compared size, resistance, tolerance, TCR, rated power, packaging and termination across all 93,914 shared rows: 0 differences in 7 fields. Only the series label is worded differently, so join on part number, never on the series name.
Does Venatech have a datasheet for Walsin thin film resistors?
No. We hold 28 Walsin datasheets, 451 pages: 26 MLCC and 2 chip resistor. None covers thin film, inductor, varistor, disc capacitor, RF or antenna. For thin film, confirm every specification against Walsin’s own site before you qualify a part.