Automotive electronics manufacturing in Guadalajara, Mexico, that wants a soft-termination capacitor at 630 V or higher has 17 Walsin Technology (Walsin) ST series parts to choose from, out of 118 in the series. The ST series is the only AEC-Q200 line to reach 1812, 1825 and 2220, and none of its parts is on our shelf.
Venatech Limited, an authorised Walsin distributor in Hong Kong, wrote this from the Walsin MLCC export (24,026 rows, 23,601 distinct part numbers) and our stock list as at 23 September 2026. It is for a purchasing or design engineer at an automotive electronics plant in the Guadalajara area who must keep an automotive series on the bill of materials and also needs a high-voltage rating. Every part number is real and every count is ours. The market statements name their sources and the day we fetched them, 10 November 2026.
What do the Jalisco export report and the USI plant report say, and why does a component buyer care?
They describe a state whose exports are mostly electronics. According to Mexico Business News on 15 January 2026, citing INEGI, Jalisco exported 13.84 billion US dollars in the third quarter of 2025, up 89.1 percent on a year earlier against 9.2 percent nationally, and electronics made up 72 percent of the total.
The same report puts electronics and high-technology exports at nearly 10 billion US dollars for the quarter. It does not mention the automotive sector. On the plant side, Mexico News Daily reported on 17 July 2024 that Universal Scientific Industrial (USI) opened a second plant in Tonalá, in the Guadalajara metropolitan area, an investment of 82 million US dollars with about 3,000 jobs, and that the state governor described USI as making electronic products for automotive, consumer and communications customers. Those are the reports’ figures, not ours. We have no relationship with USI or any other Jalisco plant and say nothing about what they buy.
Which Walsin AEC-Q200 capacitors reach 630 V or more, and in which series?
Two series do, and they stop in different places. We counted the Walsin MLCC export (00_ALL_MLCC_parts_combined.xlsx): the MT series has 87 parts at 630 V or more among its 2,176 rows, topping out at 1,250 V and at 1210, while the ST soft-termination series has 17 among 118 rows, reaching 3,000 V and 2220.
By case size, the 87 MT parts are 51 in 1206, 25 in 1210 and 11 in 0805; the MT series has no part larger than 1210. Of the ST series’ 17, 7 are in sizes MT does not offer at all: 1 in 1812, 2 in 1825 and 4 in 2220. Five of those seven are rated 3,000 V. A designer who has chosen soft termination for board-flex reasons on a large module, and who needs a high rating, is therefore choosing among a small set. Our post on why soft termination exists explains the flex case, and the post on the soft-termination series lists the families.
Which Walsin parts answer a 1 kV, 4.7 nF X7R brief at 1206, and what differs?
Only one series gives that exact combination in an automotive series at that size. For a 1206, X7R, 4.7 nF, plus or minus 10 percent, 1,000 V brief with AEC-Q200 and soft termination required, the ST series has ST31B472K102; the MT series stops at 630 V in 1206 and reaches 1,000 V at 4.7 nF only in 1210.
| Walsin part | Series | Size | Value / tolerance / voltage | On shelf 23 Sep 2026 | Match / mismatch with the brief | Your incumbent |
|---|---|---|---|---|---|---|
ST31B472K102 |
ST, AEC-Q200 soft termination | 1206 | 4.7 nF, plus or minus 10%, 1,000 V | No | Match on every field of the brief | |
ST31B472J102 |
ST | 1206 | 4.7 nF, plus or minus 5%, 1,000 V | No | Match on size, value, voltage; tighter tolerance than asked | |
MT31B472K631 |
MT, AEC-Q200, standard termination | 1206 | 4.7 nF, plus or minus 10%, 630 V | No | Mismatch: 630 V, not 1,000 V, and no soft termination | |
MT32B472K102 |
MT | 1210 | 4.7 nF, plus or minus 10%, 1,000 V | No | Mismatch: size 1210 and no soft termination | |
1206B472K102 |
Middle to High Voltage, not automotive | 1206 | 4.7 nF, plus or minus 10%, 1,000 V | Yes | Match on size, value, tolerance, voltage; mismatch: no automotive series, no soft termination |
A match in the table is a match on the export fields and no more. Walsin’s own wording is qualified to AEC-Q200, never certified; ask for the qualification report for the exact part number, and see our post on what AEC-Q200 actually certifies. Confirm against both datasheets and qualify in your own circuit.
What does the Hong Kong shelf hold at 630 V and above?
A stocked set that is entirely outside the automotive series. Of the 2,983 MLCC export rows rated 630 V or more, 116 rows are on our stock list as at 23 September 2026, and none of them is an MT or ST part; all of the AEC-Q200 series’ 2,294 rows are unstocked.
The shelf lines at this voltage come from the Middle to High Voltage series, the SH soft-termination series, the Big Sizes series and the S2 safety series. That is useful if your qualification route allows a non-automotive part, and no help if it does not. The ready stock list is a dated snapshot, never live-synced, and the MLCC range lists the families. We re-counted the snapshot ourselves: 1,125 distinct part numbers. For an AEC-Q200 series part, the enquiry is a to-order one, and we give no lead time or price.
What will we not tell you about automotive electronics makers?
Anything about their approval route, customer requirements or purchasing. Of the 28 Walsin datasheets we hold, 26 cover MLCC series, and none names a Mexican plant or a vehicle programme, so every count here is catalogue coverage and not a statement about suitability.
We make no claim that any part suits a vehicle application, and none is a certified part; Walsin says qualified to or compliant. We hold no ISO 9001 or IATF 16949 certificate, and the 451 pages of datasheets we hold do not include PPAP, IMDS or a Declaration of Conformity. We hold no office, entity or stock in Mexico; our locations are Hong Kong, Shenzhen, Singapore and Jiangmen, with Chengdu in preparation. We give no legal, customs or conformity advice; confirm with your compliance team.
How can Venatech help a Guadalajara automotive EMS buyer?
How Venatech helps starts with a free paste box. The cross-reference tool, VenaMatch, decodes 18 manufacturers’ part numbers across 800,000+ crossable parts, takes up to 500 part numbers or an Excel or CSV file, and marks each field of a Walsin candidate as match or mismatch, with a grade filter for automotive. Load a whole BOM for review, or check the ready-stock list, a Hong Kong snapshot dated 23 September 2026.
Worked example from our own export: a 1206, 4.7 nF, 1,000 V, soft-termination brief returned one exact ST match, a tighter-tolerance sibling, and two near neighbours that fail on voltage or size. Walsin is the only line we are authorised for. Stackpole and Viking are lines we supply. We serve from Hong Kong in small lots, we help cross-reference, and you request a quote through the site.
The short version
For a Guadalajara automotive board, the high-voltage automotive soft-termination shelf is small: 17 ST parts at 630 V or more, 7 of them in sizes the MT series does not make, none stocked. Check whether your voltage and size exist in the ST series before you commit the footprint.
Send us one high-voltage line from your BOM, with the series label you must keep, and we will return the Walsin parts with every difference stated. If the series label is fixed, which can move: the voltage or the case size?
Sources
Fetched 10 November 2026.
- Mexico Business News, “Jalisco posts record exports in 3Q25 driven by electronics”, 15 January 2026: https://mexicobusiness.news/trade-and-investment/news/jalisco-posts-record-exports-3q25-driven-electronics
- Mexico News Daily, “Shanghai-based USI opens new manufacturing plant in Tonalá, Jalisco”, 17 July 2024: https://mexiconewsdaily.com/business/usi-open-plant-tonala
Related reading
- Soft-termination MLCC: SH, SG, ST and VT
- AEC-Q200 MLCC: the MT and MG series
- What AEC-Q200 actually certifies
- Free tools: VenaMatch cross reference and the ready stock list
Last reviewed 10 Nov 2026.
Frequently asked questions
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What did Mexico Business News report about Jalisco exports?
On 15 January 2026 it reported Jalisco exports of 13.84 billion US dollars in the third quarter of 2025, up 89.1 percent against 9.2 percent nationally, with electronics at 72 percent of the total. It did not mention the automotive sector. These are the report’s figures.
How many Walsin AEC-Q200 soft-termination capacitors reach 630 V?
17 of the 118 in the ST series: 8 in 1206, 2 in 1210, 1 in 1812, 2 in 1825 and 4 in 2220. The highest rating is 3,000 V. Confirm each against its datasheet and ask for the qualification report.
Does the MT series have a part larger than 1210?
No. The MT series has 2,176 rows in six sizes from 0201 to 1210, and its highest rating is 1,250 V. The 1812, 1825 and 2220 sizes appear in the AEC-Q200 range only in the ST series.
Which Walsin part matches a 1206, 4.7 nF, 1 kV, soft-termination, AEC-Q200 brief?
ST31B472K102 matches every field in the export, with ST31B472J102 as a tighter-tolerance sibling. Neither is on our shelf. Qualify in your own circuit and request the qualification report for the exact part number.
Is any AEC-Q200 series part on the Hong Kong shelf?
No. None of the 2,294 MT and ST rows is on our stock list as at 23 September 2026. A non-automotive Middle to High Voltage part, 1206B472K102, is stocked, which helps only if your route allows it.
Do you hold stock or an office in Mexico?
No. We hold no office, entity or stock in Mexico; our locations are Hong Kong, Shenzhen, Singapore and Jiangmen. We hold no ISO 9001 or IATF 16949 certificate and give no legal, customs or conformity advice. Confirm with your compliance team.