EV powertrain electronics for Thailand hit a wall at 1 µF. Walsin’s export lists 50 AEC-Q200 MLCC at 1 µF or more and 25 V or more, all X7R, none X5R. Of the 20 lines on our 23 September 2026 shelf at that level, 8 have an AEC-Q200 twin, 6 only an MG part, and 6 none.
Venatech Limited, an authorised Walsin distributor in Hong Kong, holds the Walsin Technology (Walsin) MLCC export, 24,026 rows and 23,601 distinct part numbers, and a ready-stock list dated 23 September 2026 with 864 MLCC lines. This post is for a purchasing or design engineer at a Thai maker of EV motors, inverters or battery electronics who needs a second source for the 1 µF-class capacitors on a supply or gate-drive rail. Every part number below is real and every count is ours. The market statements name their sources and the day we read them, 23 October 2026.
What do Thailand’s EV 3.5 rules ask of makers in 2026 and 2027?
They ask for local output. Krungsri Research reported on 2 December 2025 that makers which received EV 3.5 benefits and imported battery-electric cars in 2024 and 2025 must offset that volume with local production, at twice the imported volume for production starting in 2026 and three times for 2027. It also reported 84,546 new passenger battery-electric registrations in the first nine months of 2025, up 60.4 percent, or 48.9 percent of passenger car registrations.
A separate report dated 25 September 2024, carried by AFMA, said makers in the 3.0 and 3.5 programmes must produce three key components in Thailand by 2026: the electric motor, the reducer and the inverter. The two sources describe different obligations and we do not reconcile them. Neither mentions capacitors or any named supplier, and we draw no conclusion about what any maker buys. We have no relationship with Krungsri, AFMA or any Thai maker. The inference is ours: a motor and an inverter built at home have a bill of materials built at home, and its ceramic capacitors come from somewhere.
How many AEC-Q200 Walsin MLCC reach 1 µF at 25 V or more?
Fifty. We parsed all 24,026 rows of Walsin’s MLCC export and kept parts at 1 µF or more and 25 V or more: 476 in all, of which 72 sit in an automotive series, 26 in MT and 24 in ST, both AEC-Q200 series, and 22 in MG, which is not. All 50 AEC-Q200 parts are X7R. Six of the 22 MG parts are X5R. We have not seen this counted anywhere.
We take 25 V as the floor for a 20 V rail under an 80 percent derating rule, which is our scenario and not a standard; use your own rule. The ceiling by case size is the other half of the finding.
| Case | AEC-Q200 parts at 1 µF or more, 25 V or more | Largest capacitance | Match / mismatch |
|---|---|---|---|
| 0805 | 6 | 1 µF | Mismatch if you need more than 1 µF: nothing larger in 0805 |
| 1206 | 18 | 10 µF | Match on X7R only; mismatch for X5R |
| 1210 | 25 | 22 µF | Match on X7R only |
| 2220 | 1 | 10 µF | One part; 12 of the 50 are at 100 V |
| 0603 | 0 | none | Mismatch: no AEC-Q200 part at 1 µF and 25 V in 0603 |
The voltage split is 12 parts at 25 V, 26 at 50 V and 12 at 100 V. Our post on MLCC DC bias and voltage derating shows why the rated capacitance is not the capacitance you get on the rail.
Which stocked lines at that level have an automotive twin?
Eight of 20. We joined the 864 MLCC lines on our 23 September 2026 list to the export and found 54 stocked lines at 1 µF or more; 20 are rated 25 V or more. For each we looked for an automotive-series part with the same case, dielectric, capacitance and voltage: 8 have an MT or ST part, 6 have only MG, and 6 have none. The 34 lines below 25 V are outside this count.
The six with none are the X5R lines (0805X105K250CT, 0805X106K250CT, 0805X106K500CT, 1206X106K500CT) and two soft-termination parts, SH31B475K500CT and SH32B335K500CT. None of the automotive twins is on the shelf, and no MT, MG or ST line is in our 864.
Which worked lines show the twins, and what differs?
Height is what differs most. 1206B105K250CT has an MT twin, MT31B105K250, that matches on every listed field including height; 1210B106K250CT has MT and ST twins that print 2.50 mm against the stocked line’s 2.00 mm. The last column is for your incumbent part.
| Stocked line | Automotive-series part | Fields as exported | Match / mismatch | Your incumbent |
|---|---|---|---|---|
0805B105K250CT, X7R, 1 µF, 25 V, plus or minus 10%, 1.25±0.20 mm |
MT21B105K250 |
Same, 1.25±0.10 mm | Match on size, dielectric, capacitance, voltage, tolerance; mismatch on printed height band | |
1206B105K250CT, X7R, 1 µF, 25 V, 1.15±0.15 mm |
MT31B105K250 |
Same, 1.15±0.15 mm | Match on every listed field; mismatch on series | |
1206B105K500CT, X7R, 1 µF, 50 V, 1.60+0.30/-0.10 mm |
MT31B105K500 |
Same, 1.60+0.30/-0.10 mm | Match on every listed field; mismatch on series | |
1210B106K250CT, X7R, 10 µF, 25 V, 2.00±0.20 mm |
MT32B106K250 |
2.50±0.30 mm | Match on capacitance, voltage, tolerance; mismatch on height by 0.5 mm | |
1210B106K250CT |
ST32B106K250 |
Soft termination | Match on capacitance, voltage, tolerance; mismatch on termination | |
1210B475K500CT, X7R, 4.7 µF, 50 V, plus or minus 10% |
ST32B475J500 |
Plus or minus 5%, 2.50±0.50 mm | Mismatch: ST lists J and M at this value, not K | |
1206B225K250CT, X7R, 2.2 µF, 25 V |
MG31B225K250 |
MG, not AEC-Q200 | Mismatch: no MT or ST part at this value | |
0805X106K250CT, X5R, 10 µF, 25 V |
none | No automotive row | Mismatch: no automotive part |
A 0.5 mm height change at 1210 is a layout question, not a footnote. The MG tolerance column prints values such as -0.1, so we did not compare tolerance on MG rows. Our post on the MT and MG series explains the split, and the one on what AEC-Q200 actually certifies covers the wording.
What will we not tell you about Thailand?
Anything about Thai investment promotion, excise or customs rules. We hold no office, entity or stock in Thailand; our locations are Hong Kong, Shenzhen, Singapore and Jiangmen, with Chengdu in preparation. We state no duty rate, transit time or carrier, and we give no legal or customs advice; confirm with your compliance team. We hold neither ISO 9001 nor IATF 16949, and we make no claim that any Walsin part is approved for a Thai programme.
How Venatech helps
Start with one capacitor line. Paste it into the free cross-reference tool, which decodes 18 manufacturers’ part numbers across 800,000+ crossable parts and lists Walsin candidates with match and mismatch fields, or upload a list to the BOM checker, up to 500 part numbers or an Excel or CSV file. The Hong Kong ready-stock list is a dated snapshot, 23 September 2026, never live-synced; it holds no automotive-series MLCC line, so an AEC-Q200 part is a quote request. Walsin is the only line we are authorised for; Stackpole and Viking are lines we supply. We work from Hong Kong, in small lots, and you can request a quote through the site. The MLCC range lists the series. Qualification stays with you.
The short version
At 1 µF and 25 V or more, the AEC-Q200 shelf is X7R only, 50 parts, and 0603 is empty. Of 20 stocked lines at that level, 8 have an MT or ST twin, 6 only MG and 6 none, and two twins differ in height by up to 0.5 mm. Confirm against both datasheets and qualify in your own circuit.
Send us your 1 µF lines and we will return the Walsin parts with every difference stated. Does your rail need X5R capacitance, or only X7R behaviour?
Sources
Fetched 23 October 2026. The market statements come from these pages; the counts come from our own Walsin export, stock list and datasheets.
- Krungsri Research, “Industry Outlook 2026-2028: Electric Vehicle Industry”, dated 2 December 2025: https://www.krungsri.com/en/research/industry/industry-outlook/hi-tech-industries/electric-vehicle/io/electric-vehicle-bev-2026-2028
- AFMA, “Thailand urges EV makers to produce key components locally by 2026”, dated 25 September 2024: https://afma.org.au/thailand-urges-ev-makers-to-produce-key-components-locally-by-2026/
Frequently asked questions
<!– wp:rank-math/faq-block {"questions":[{"id":"faq-question-01","title":"How many AEC-Q200 Walsin MLCC reach 1 µF at 25 V or more?","content":"50: 26 in the MT series and 24 in ST, all X7R. The MG series adds 22 parts, 6 of them X5R, but MG is automotive without AEC-Q200. We parsed all 24,026 export rows. By case size the AEC-Q200 parts are 6 in 0805, 18 in 1206, 25 in 1210 and 1 in 2220.","visible":true},{"id":"faq-question-02","title":"Is there an AEC-Q200 X5R capacitor at 1 µF and 25 V?","content":"Not in the export. The MT and ST series list X7R at this level, and every X5R part in the automotive set is in MG, which is not AEC-Q200. If your rail relies on X5R capacitance, moving to X7R is a design decision about size and capacitance under bias.","visible":true},{"id":"faq-question-03","title":"How many stocked lines at 1 µF and 25 V or more have an automotive twin?","content":"8 of 20 have an MT or ST twin on case, dielectric, capacitance and voltage, 6 have only MG, and 6 have none, as at 23 September 2026. None of the twins is on the shelf. A twin is a catalogue match, not a qualification.","visible":true},{"id":"faq-question-04","title":"Do the twins match on height?","content":"Not always.MT31B105K250 matches 1206B105K250CT at 1.15±0.15 mm. MT32B106K250 prints 2.50±0.30 mm against 2.00±0.20 mm for 1210B106K250CT, a 0.5 mm difference. Check the printed height against your layout before you swap.”,”visible”:true},{“id”:”faq-question-05″,”title”:”What do Walsin’s AEC-Q200 sheets say?”,”content”:”The MT sheet is headed \”Qualified to AEC-Q200\”; the ST sheet says compliant. We hold 28 datasheets, 451 pages, and no qualification report for a named part number. Ask Walsin for the report, and confirm with your own quality team. We make no qualification claim.”,”visible”:true},{“id”:”faq-question-06″,”title”:”Do you advise on Thai EV or customs rules?”,”content”:”No. We hold no Thai investment, excise or customs content, and no office or stock in Thailand. We give no legal or customs advice; confirm with your compliance team. We supply parts from Hong Kong in small lots and match them to your list.”,”visible”:true}],”listStyle”:””,”titleWrapper”:”h3″,”titleCssClasses”:””,”contentCssClasses”:””,”sizeSlug”:””} –>
How many AEC-Q200 Walsin MLCC reach 1 µF at 25 V or more?
50: 26 in the MT series and 24 in ST, all X7R. The MG series adds 22 parts, 6 of them X5R, but MG is automotive without AEC-Q200. We parsed all 24,026 export rows. By case size the AEC-Q200 parts are 6 in 0805, 18 in 1206, 25 in 1210 and 1 in 2220.
Is there an AEC-Q200 X5R capacitor at 1 µF and 25 V?
Not in the export. The MT and ST series list X7R at this level, and every X5R part in the automotive set is in MG, which is not AEC-Q200. If your rail relies on X5R capacitance, moving to X7R is a design decision about size and capacitance under bias.
How many stocked lines at 1 µF and 25 V or more have an automotive twin?
8 of 20 have an MT or ST twin on case, dielectric, capacitance and voltage, 6 have only MG, and 6 have none, as at 23 September 2026. None of the twins is on the shelf. A twin is a catalogue match, not a qualification.
Do the twins match on height?
Not always. MT31B105K250 matches 1206B105K250CT at 1.15±0.15 mm. MT32B106K250 prints 2.50±0.30 mm against 2.00±0.20 mm for 1210B106K250CT, a 0.5 mm difference. Check the printed height against your layout before you swap.
What do Walsin’s AEC-Q200 sheets say?
The MT sheet is headed “Qualified to AEC-Q200”; the ST sheet says compliant. We hold 28 datasheets, 451 pages, and no qualification report for a named part number. Ask Walsin for the report, and confirm with your own quality team. We make no qualification claim.
Do you advise on Thai EV or customs rules?
No. We hold no Thai investment, excise or customs content, and no office or stock in Thailand. We give no legal or customs advice; confirm with your compliance team. We supply parts from Hong Kong in small lots and match them to your list.