Passive components for Hungary’s battery and automotive lines meet a gap at high voltage. Of 2,653 Walsin MLCC part numbers rated 630 V or more, 112 sit in an automotive series. We matched 97 stocked lines against them: 7 have an automotive-series twin on five fields, and none of the 7 twins was on the Hong Kong shelf.
Venatech Limited, an authorised Walsin distributor in Hong Kong, wrote this for a buyer or design engineer in Hungary whose product sits in or near a vehicle or a battery pack. We read Walsin Technology (Walsin) 00_ALL_MLCC_parts_combined.xlsx (24,026 rows) and our Hong Kong stock snapshot dated 23 September 2026. Every part number below is real and every count is ours. The Hungarian news is attributed to its publishers, with the day we fetched it.
What did the Debrecen trial production change for a Hungarian component buyer?
Volume, eventually, and a new class of line to buy for. On 22 September 2026, two production lines at the Debrecen battery cell plant began trial production, and the plant is planned at 100 GWh. Automotive World and CarNewsChina both reported it that day. They add that the plant has made 537,000 battery modules since autumn 2024 and that series manufacturing has not yet started.
Neither report names a customer, and we name none. We say nothing about any maker’s supply position, and we do not claim that any plant or carmaker buys from us. Our view is narrower: a country that makes both vehicles and battery cells has buyers who need high-voltage parts in qualified series, and those are the parts a general stock shelf holds least. We hold no office, entity or stock in Hungary. Our locations are Hong Kong, Shenzhen, Singapore and Jiangmen, and Chengdu is in preparation. Duty, customs and transit are for your forwarder and compliance team to confirm.
How many Walsin high-voltage MLCC part numbers sit in an automotive series?
112 of 2,653, or 4.2%. We parsed all 24,026 rows, removed duplicates to reach 23,601 distinct part numbers, set aside the 173 safety-series rows, and counted the 2,653 rated 630 V or more. Of those, 87 are in the MT series, 17 in the ST series and 8 in the MG series. Walsin’s sheets describe MT and ST as AEC-Q200 compliant; the MG series is listed without it. We have not seen this counted anywhere.
We set the safety series aside because its Rated Voltage column holds impulse voltage on all 173 rows, not working voltage, a defect we have published before. The remaining ratings are DC working ratings as the export states them. Walsin’s MT sheet (11_Automotive_MT.pdf, 29 pages) covers 10 V to 1,000 V in its summary, and the export holds one MT part at 1,250 V, MT32N103J12E. The high-voltage sheet (04_Middle_and_High_Voltage.pdf, 13 pages) and the ST sheet (12_Soft_Term_Automotive_ST.pdf, 23 pages) hold the construction detail. Whether a given pack voltage allows a 630 V or 1,000 V part is your derating decision, and our DC bias post shows why headroom matters.
Which stocked high-voltage lines have an automotive-series twin?
Seven of 97. We joined the 97 distinct stocked lines rated 630 V or more to the export and tested each against every MT and ST part on five fields: case size, dielectric, capacitance, tolerance and rated voltage. Seven lines have a twin. The other 90 do not, including all 23 stocked 1812 lines and all 14 stocked 1808 lines, because the export has no automotive 1808 part.
| Stocked Walsin line (23 Sep 2026) | Automotive-series twin | Spec | Published thickness (mm), stocked / twin | Your incumbent | Match / mismatch |
|---|---|---|---|---|---|
1206B103K631 |
MT31B103K631 |
1206 X7R 10 nF ±10% 630 V | 1.25 ±0.10 / 1.25 ±0.10 | Match on all five fields and height; grade differs | |
1206B332K631 |
MT31B332K631 |
1206 X7R 3300 pF ±10% 630 V | 1.25 ±0.10 / 1.25 ±0.10 | Match on all five fields and height; grade differs | |
1210B472K102 |
MT32B472K102 |
1210 X7R 4700 pF ±10% 1000 V | 1.60 ±0.20 / 1.60 ±0.20 | Match on all five fields and height; grade differs | |
SH21B332K631 |
MT21B332K631 |
0805 X7R 3300 pF ±10% 630 V | 0.80 ±0.10 / 0.80 ±0.10 | Match on five fields; termination construction differs (SH soft termination against MT) | |
SH31N221J102 |
MT31N221J102 |
1206 NP0 220 pF ±5% 1000 V | 1.60 ±0.20 / 1.60 ±0.20 | Match on five fields; termination construction differs | |
1206B472K102 |
ST31B472K102 |
1206 X7R 4700 pF ±10% 1000 V | 1.25 ±0.10 / 1.60 ±0.20 | Mismatch on height (twin 0.35 mm taller) and soft termination | |
1206B222K102 |
ST31B222K102 |
1206 X7R 2200 pF ±10% 1000 V | 1.25 ±0.10 / 1.60 ±0.20 | Mismatch on height (twin 0.35 mm taller) and soft termination | |
1812B331K202 |
none | 1812 X7R 330 pF ±10% 2000 V | 1.25 ±0.10 / none | Mismatch: no automotive part at this size, dielectric, value and voltage |
None of the twins was on the shelf on 23 September 2026: we found 0 of 764 stocked MLCC lines in an automotive series. A twin match is a specification match on five exported fields. It is not an approval, and the grade column in our table is the point of the exercise, not a footnote. Request the qualification report for the exact twin and read the Walsin sheet for its series (11_Automotive_MT.pdf or 12_Soft_Term_Automotive_ST.pdf). The free cross-reference tool decodes 18 manufacturers’ part numbers across 800,000+ crossable parts, so you can paste your own incumbent against the same fields.
Why does an automotive-series twin sometimes come taller?
Because soft termination adds metal and resin at the ends. Two of the seven twins, both in the ST series at 1206 and 1000 V, publish 1.60 ±0.20 mm where the stocked part publishes 1.25 ±0.10 mm. That is a worst case of 1.80 mm against 1.35 mm, or 0.45 mm more.
Height is the field a “same value, same voltage” search never shows. On a board with a clearance limit it decides the swap. The export gives the thickness for these parts and we read it for every row in the table above. Two other rows need care. ST31N103J631 carries N and J in its own code, which Walsin’s ordering key reads as NP0 and ±5%, but its export columns say X7R and ±10%, and its thickness is empty. We excluded it from every count and we would not order from that row without Walsin’s confirmation.
Our earlier posts on dielectric and voltage in stock and on varistor voltage steps for Hungary cover other fields on the same shelf.
What can you not conclude from this list?
That the 90 lines without a twin are unsuitable, or that the 7 are approved. We hold 28 Walsin datasheets, 451 pages, and eighteen document types appear nowhere in them: IATF 16949, PPAP, IMDS, REACH and a declaration of conformity among them. Those are not in the documents we hold, and we say so. Venatech holds no IATF 16949 or ISO 9001 claim.
What we can supply is a lot and date-code record, a certificate of conformity with each shipment on request, and original sealed Walsin packaging. UL file E182369 can be checked in UL’s public database. For a whole BOM, the BOM checker takes up to 500 part numbers or an Excel or CSV file, and Hong Kong ready stock shows the dated shelf. Browse the Walsin MLCC range. Confirm against both datasheets, and qualify in your own circuit.
The short version
Of 2,653 Walsin MLCC part numbers rated 630 V or more, 112 are in an automotive series. Of 97 lines on the Hong Kong shelf on 23 September 2026, 7 have an AEC-Q200-series twin on five fields, 2 of those twins are taller, and none of the twins was stocked. A twin is a candidate, not an approval.
Send us the high-voltage lines from your pack or vehicle BOM and we will return the Walsin candidates with every difference stated, height included. Qualification stays with you. When your last high-voltage swap failed, was it voltage, grade or height?
Sources
Fetched 20 October 2026. The news statements above are taken from these pages; the part data comes from our own Walsin export and stock list.
- Automotive World, “CATL begins trial production at its Debrecen cell plant”, dated 22 September 2026: https://www.automotiveworld.com/news/catl-begins-trial-production-at-its-debrecen-cell-plant/
- CarNewsChina, “CATL’s Hungarian plant with a planned 100 GWh capacity begins trial production today”, dated 22 September 2026: https://carnewschina.com/2026/09/22/catls-hungarian-plant-with-a-planned-100-gwh-capacity-begins-trial-production-today/
Frequently asked questions
Which Walsin MLCC suit high-voltage automotive lines in Hungary?
Few are in an automotive series. Of 2,653 Walsin part numbers rated 630 V or more, 112 are in the MT, ST or MG series, and the MG series is listed without AEC-Q200. Check the Walsin sheet for your exact part and request its qualification report.
How many stocked high-voltage lines have an automotive-series twin?
Seven of 97 stocked lines rated 630 V or more match an MT or ST part on size, dielectric, capacitance, tolerance and voltage. None of the 7 twins was on our shelf on 23 September 2026. A twin is a candidate for evaluation, not an approval.
Is the automotive-series twin always the same height?
No. Two ST-series twins at 1206 and 1000 V publish 1.60 ±0.20 mm against 1.25 ±0.10 mm for the stocked part. The MT twins in our table publish the same thickness as the stocked part. Compare thickness before you swap.
Are Walsin MT and ST parts AEC-Q200 certified?
Walsin’s sheets say compliant, not certified, and we make no qualification claim of our own. Ask for the qualification report for the exact part number, and qualify the part in your own circuit before production.
Do you have stock or an office in Hungary?
No. Our locations are Hong Kong, Shenzhen, Singapore and Jiangmen, with Chengdu in preparation. We state no duty, customs procedure or transit time. Your forwarder and compliance team confirm the import side; we supply parts, lot and date-code records and, on request, a certificate of conformity.
Do you supply the Debrecen plant or any named carmaker?
We make no claim about any named plant or carmaker, and the sources we cite name no customer. We describe only what Walsin parts we hold and how they cross.