An AEC-Q200 high voltage MLCC at 4.7 nF, 1000 V, X7R is a short list in Walsin’s range: we counted 20 part numbers, and 4 are in an AEC-Q200 series, three of them soft-termination 1206 parts. The 2 on our Hong Kong shelf are commercial Middle to High Voltage parts, with a lower height than the AEC-Q200 1206.
Venatech Limited, an authorised Walsin distributor in Hong Kong, wrote this for a design or sourcing engineer at an EV or automotive electronics maker in Rayong or elsewhere in Thailand’s Eastern Economic Corridor, picking a snubber, filter or isolation-side ceramic capacitor for an 800 V class design. Walsin Technology (Walsin) is the only line we are authorised for. We re-measured Walsin’s MLCC export (24,026 rows, 23,601 distinct part numbers) on 11 November 2026 against our stock list as at 23 September 2026. Every part number is real.
What is happening in Thailand’s EV supply chain, from Rayong to the BOI?
Assembly at scale, with materials following. Pattaya Mail reported on 21 September 2026 that BYD’s Rayong plant builds about 5,000 to 6,000 vehicles a month on one shift, exported about 40 percent of its first-half 2026 output, and has 266 suppliers on its pool list, 125 of them auto parts makers.
On 24 October 2026 the Thailand Board of Investment said 35 advanced materials projects worth about 23.5 billion baht had been filed since 2023, including battery foil and EV motor magnet makers. We fetched both on 11 November 2026; the figures are theirs. Our inference: a supplier base that grows around an EV plant will be asked for automotive-grade ceramic capacitors at high voltage, and that is a narrow part of any catalogue. We have no relationship with BYD or any project named and say nothing about what they buy.
Which Walsin parts cross a 4.7 nF, 1000 V, X7R brief, and which are AEC-Q200?
Four of twenty. We filtered the export for 4.7 nF, 1000 V, X7R: 20 part numbers in four series, 12 Middle to High Voltage, 4 SH soft termination, 3 ST and 1 MT; only the ST and MT parts sit in series Walsin labels Qualified to AEC-Q200.
Put your incumbent in the last column. The brief is 1206, plus or minus 10 percent, AEC-Q200.
| Walsin part | Series | Size | Height (mm) | On shelf 23 Sep 2026 | Match / mismatch with the brief | Your incumbent |
|---|---|---|---|---|---|---|
ST31B472K102 |
ST soft termination, AEC-Q200 | 1206 | 1.60 plus or minus 0.20 | No | Match on every field | |
ST31B472J102 |
ST soft termination, AEC-Q200 | 1206 | 1.60 plus or minus 0.20 | No | Mismatch: 5 percent tolerance | |
MT32B472K102 |
MT, AEC-Q200 | 1210 | 1.60 plus or minus 0.20 | No | Mismatch: 1210 | |
1206B472K102 |
Middle to High Voltage | 1206 | 1.25 plus or minus 0.10 | Yes | Mismatch: commercial series, lower height | |
SH31B472K102 |
SH soft termination | 1206 | 1.25 plus or minus 0.10 | No | Mismatch: commercial series |
A voltage rating is not a working voltage, and Class II capacitance falls with applied voltage, so derate for your circuit. Confirm against both datasheets and qualify in your own design; our post on MLCC DC bias and voltage derating covers the method.
Where does an AEC-Q200 high voltage MLCC at 1000 V exist in 1206?
Only in the ST soft-termination series, for X7R. We counted every AEC-Q200 X7R part at 1000 V in 1206: 7, all ST, from 1.5 nF to 4.7 nF; the MT series reaches 1000 V in 1206 only in NP0, 5 parts from 56 pF to 470 pF such as MT31N471J102.
MT X7R at 1000 V starts at 1210, with 9 parts topping out at 10 nF in MT32B103K102. Above that, the AEC-Q200 X7R ladder at 1000 V jumps to 100 nF in 1825 with ST46B104K102. Across all sizes and dielectrics we count 36 AEC-Q200 part numbers at 1000 V or more. The 1206 split by dielectric is our cut, and we have not seen it set out anywhere. For the series background, see AEC-Q200 MLCC: MT versus MG.
Does the datasheet we hold cover the 1000 V AEC-Q200 parts?
Not for ST. We read the index of the 26 MLCC datasheets we hold: the ST sheet, 12_Soft_Term_Automotive_ST.pdf, covers 0603 to 0805 and 10 to 50 V, while the export lists ST parts at 1000 V to 3000 V in 1206 to 2220.
The MT sheet, 11_Automotive_MT.pdf, covers 10 to 1000 V and 0201 to 1210, so it spans MT32B472K102. It does not reach the one MT part rated 1250 V. A buyer who designs in a 1000 V ST part should ask for the datasheet and AEC-Q200 qualification report for that exact part number. Walsin’s datasheets say compliant or qualified, not certified, and Venatech makes no qualification claim of its own.
What does our Hong Kong shelf hold at 4.7 nF and 1000 V?
Two commercial parts and no automotive ones. We matched the 20 parts to our stock list as at 23 September 2026: 1206B472K102 and 1210B472K102, both Middle to High Voltage, are on the shelf; none of the 3,076 automotive-series MLCC part numbers is.
The shelf 1206 part is 1.25 mm high against 1.60 mm for ST31B472K102, so a height-limited board may accept one and not the other. The ready stock list is a dated snapshot, never live-synced; ask through the site for to-order options on the AEC-Q200 parts.
How Venatech helps: what should a Thai EV electronics team do next?
Paste the high voltage lines with the grade filter on. The free cross-reference tool, VenaMatch, decodes 18 manufacturers’ part numbers and covers 800,000+ crossable parts; filter by commercial or automotive grade, or for soft termination, and each Walsin candidate returns with every field marked match or mismatch. Upload a BOM, and see the MLCC range.
Worked example from our export: the 4.7 nF, 1000 V, X7R, 1206 brief returned 1 full AEC-Q200 match and a shelf part that differs in grade and height. We serve from Hong Kong, welcome small lots, and you request a quote through the site. We hold no office, entity or stock in Thailand, hold no ISO 9001 or IATF 16949 certificate, and give no customs or conformity advice; confirm with your compliance team. Qualification stays with you.
The short version
- 4.7 nF, 1000 V, X7R: 20 Walsin part numbers, 4 in AEC-Q200 series.
- In 1206, AEC-Q200 X7R at 1000 V exists only in ST soft termination, 7 parts.
- The ST datasheet we hold covers 10 to 50 V only; ask for the current sheet.
- 2 commercial 4.7 nF, 1000 V parts are on our shelf; no automotive MLCC is.
Send us the high voltage capacitor lines from your EV BOM with the grade you need, and we will return the Walsin parts with every difference stated.
Sources, fetched 11 November 2026:
- Pattaya Mail, “BYD’s Rayong plant emerges as major EV hub for global markets”, 21 September 2026: https://www.pattayamail.com/latestnews/news/byds-rayong-plant-emerges-as-major-ev-hub-for-global-markets-565734
- Thailand Board of Investment, press release 188/2569 on advanced materials investment, 24 October 2026: https://www.boi.go.th/upload/content/PR188_2569EN.pdf
- Walsin MT datasheet: https://www.passivecomponent.com/wp-content/uploads/datasheet/WTC_MLCC_Automotive_MT.pdf
Frequently asked questions
Which Walsin AEC-Q200 high voltage MLCC matches 4.7 nF, 1000 V, X7R, 1206?
ST31B472K102, in the ST soft-termination series, 10 percent tolerance, 1.60 mm high. It matches every export field of that brief. Confirm against its datasheet and the qualification report for the exact part number.
How many Walsin 4.7 nF, 1000 V, X7R capacitors are there?
We counted 20: 12 Middle to High Voltage, 4 SH soft termination, 3 ST and 1 MT. Four are in series labelled Qualified to AEC-Q200. Two commercial parts are on our shelf as at 23 September 2026.
Does the Walsin MT series offer X7R at 1000 V in 1206?
Not in the export. MT reaches 1000 V in 1206 only in NP0, 56 pF to 470 pF. MT X7R at 1000 V starts at 1210, up to 10 nF. In 1206, X7R at 1000 V with AEC-Q200 is ST only.
Is a 1000 V rating enough for an 800 V EV design?
That is your design decision. A rated voltage is not a working voltage, and X7R capacitance falls under DC bias. Derate for your circuit, check creepage and clearance, and qualify the part in your own design.
What did BYD’s Rayong plant report?
Pattaya Mail reported on 21 September 2026 that the plant builds about 5,000 to 6,000 vehicles a month on one shift, exported about 40 percent of first-half 2026 output, and lists 266 suppliers. Those are the report’s figures.
Do you hold automotive MLCC stock or an office in Thailand?
No automotive-series MLCC is on our 23 September 2026 shelf, and we have no office, entity or stock in Thailand. We serve from Hong Kong, Shenzhen, Singapore and Jiangmen. Ask through the site for to-order options.