Automotive Ferrite Bead: Two Series, 289 Rows, No AEC-Q200 Column Anywhere

An automotive ferrite bead in Walsin’s catalogue comes from one series, MCB / MHC Automotive, 150 rows, with no AEC-Q200 marker anywhere in the export. A second series, MCI Automotive, 139 rows, reads nH in Unit, not Ω — it is an inductor, not a bead. Together, 289 rows, and neither is flagged qualified.

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Venatech Limited, an authorised Walsin distributor in Hong Kong, holds Walsin_Inductor_ALL.xlsx, Walsin Technology (Walsin)’s full parametric inductor export, 5,410 real part numbers across 47 series once the one QA test row is excluded. Every count below is measured directly from that file, and every part number is real.

How many automotive inductor rows does Walsin publish, across which series?

289, split across two series that both carry the word “Automotive” in their name but describe two different kinds of component. MCB / MHC Automotive holds 150 rows and MCI Automotive holds 139, for a combined 289 of the catalogue’s 5,410 real rows, 5.3%. We have not seen the two totalled together before, because they sit on opposite sides of the bead/inductor split this export otherwise hides.

Series	Rows	Unit column	What it actually is
MCB / MHC Automotive	150	Ω on all 150	Ferrite bead
MCI Automotive	139	nH on all 139	Genuine inductor
Combined “Automotive” total	289	—	—

Which of the two automotive series is actually a ferrite bead?

Only MCB / MHC Automotive. We read the Unit column on all 150 of its rows and all 150 say Ω — an impedance, not an inductance — which puts it inside the 641-row bead population we measured separately across the whole catalogue. MCI Automotive, despite the identical word in its series name, reads nH on all 139 of its rows with no exception: it is a genuine inductor, and treating it as a bead because of the name would be a mistake the export itself contradicts in 139 rows out of 139. Check the Unit column before you classify either series — the series name is not reliable evidence on its own.

Does any column in the export state an AEC-Q200 status?

No — not for these two series, and not for any of the other 45. Walsin_Inductor_ALL.xlsx has 14 columns total: Part Number, Series, Size, Size L*W (mm), Thickness (mm), Inductance, Impedance (100MHz), Unit, Tolerance, Q Min, SRF(min), RDC, Rated Current and Saturation Current. None of them names a qualification standard. The word “Automotive” inside a series name is the only signal in this file that a row is intended for that market, and it is a text label, not a certification field — the same situation already measured on the chip resistor side of Walsin’s catalogue, where 43.9% of rows carry “(Automotive)” as free text with no qualification column anywhere in the schema.

How closely does the automotive inductor series match its commercial counterpart?

Almost exactly, once a unit-notation quirk is corrected. We matched all 139 MCI Automotive rows against the 501-row commercial MCI series on case size, inductance and tolerance, and found a signature match for all 139. Checking every remaining electrical field — Q, SRF, RDC and rated current, with rated current normalised between the “mA” and “A” notations the two series use inconsistently — 134 of 139 (96.4%) match their commercial counterpart on every published field.

Part number	Series	Size	Inductance	Tolerance	Q Min	RDC	Rated current	Match / mismatch vs commercial MCI
MCI1608HH1N0SHBP	MCI Automotive	1608(0603)	1.0 nH	±0.3 nH	8	0.05 Ω	1000 mA	Match vs MCI1608HQ1N0SHBP on every field; part numbers differ by one letter at position 9
MCI1005HZ0N3BHBP	MCI Automotive	1005(0402)	0.3 nH	±0.1 nH	8	0.08 Ω	1000 mA	Match vs MCI1005HQ0N3BHBP on every field once “1A” and “1000mA” are read as the same value
MCI1005HZ2N4BHBP	MCI Automotive	1005(0402)	2.4 nH	±0.1 nH	8	0.13 Ω	800 mA	Mismatch — commercial MCI1005HQ2N4BHBP shares every field except rated current, published at 900 mA

The 5 of 139 that do not match are genuine mismatches, not notation — one, shown above, is rated lower than its commercial twin at identical inductance, tolerance, Q and RDC. No column anywhere explains why an automotive-marked row would carry a lower current rating than the commercial part it otherwise matches exactly.

How closely does the automotive bead series match its commercial counterpart?

Far less closely than the inductor pair above, even though the headline figure agrees almost every time. We matched all 150 MCB / MHC Automotive rows against the five commercial bead series — MCB-B, MCB-H, MCB-S, MHC-P, MHC-S — first on case size and 100 MHz impedance alone, then on every published electrical field together.

Match basis	Automotive rows matching	Share of 150
Case size and 100 MHz impedance only	137	91.3%
Every published electrical field (size, impedance, tolerance, RDC, rated current)	19	12.7%

Part number	Series	Size	Impedance (100 MHz)	RDC	Rated current	Match / mismatch vs commercial candidates
MHC2012S300RZP	MCB / MHC Automotive	2012(0805)	30 Ω	0.014 Ω	3300 mA	Match on case and impedance vs MCB2012S300KBP and MHC2012S300QBP; mismatch on RDC and rated current against both
MCB2012S300KBP	MCB-S (commercial)	2012(0805)	30 Ω	0.05 Ω	800 mA	Shares case and impedance with the automotive row; mismatch — more than 3x the RDC, less than a quarter the current
MHC2012S300QBP	MHC-S (commercial)	2012(0805)	30 Ω	0.04 Ω	3000 mA	Closest commercial candidate to the automotive row on RDC and rated current; still mismatch by series name alone

That is the opposite pattern from the inductor pair. An automotive inductor almost always matches its commercial twin on every field; an automotive bead usually shares only the one number most buyers filter on — the 100 MHz impedance — and diverges on RDC and rated current 87.3% of the time. We will not tell you any candidate in either table is equivalent. Confirm against the Walsin datasheet, where we do not hold one, and qualify in your own circuit regardless.

Does the automotive bead series reach the same case sizes as its commercial counterpart?

No — it stops two sizes short. MCB / MHC Automotive is published at 1005(0402) through 4532(1812), seven distinct sizes. The commercial MCB-S series alone reaches the same seven. But MCI Automotive, the inductor series, is published only at 1005(0402) and 1608(0603) — it never reaches 0603(0201), where the commercial MCI series places 349 of its 501 rows (69.7%) and the commercial MCI-TM series places all 172 of its rows. The smallest automotive inductor footprint Walsin’s export offers is one full case size larger than the smallest commercial one.

What should a buyer ask for before specifying an automotive bead or inductor?

The AEC-Q200 qualification report for the exact part number, because the export cannot supply it. The series name “Automotive” is real and consistent — every row we checked in both series carries it — but it is a text label, not a certificate, and Walsin’s own compliant/certified distinction (where we hold it in writing for other product lines) is not visible anywhere in this file.

1. Ask for the qualification report, not the series name. We will request it from Walsin for your specific part number; we make no qualification claim of our own.
2. Check whether your case size exists at all in the automotive series. MCI Automotive stops at 0603(0201) one step above the smallest commercial part — confirm before you design to a footprint the automotive series does not reach.
3. Cross the part on our free cross reference tool. It matches against 800,000+ crossable Walsin part numbers and states every difference field by field, automotive or commercial.
4. Check ready stock — a dated snapshot as at 23 September 2026 — before committing a production slot to either series.

For how the Unit column separates every bead from every inductor across the whole 5,410-row file, see Ferrite bead selection: 641 of Walsin’s 5,410 inductor rows are not inductors. For the automotive chip resistor split, which has the same “name without a qualification column” pattern, see Walsin automotive chip resistors: MR, SR and the AEC-Q200 split. The full range is on the Walsin inductor range page.

The short version

Walsin’s inductor export carries 289 rows marked “Automotive” across two series, and they are two different kinds of component: MCB / MHC Automotive (150 rows) is a ferrite bead, MCI Automotive (139 rows) is a genuine inductor, and only the Unit column tells you which. No column in the 14-column file states AEC-Q200 status for either. The inductor pair matches its commercial counterpart on every field 96.4% of the time; the bead pair shares its headline 100 MHz impedance 91.3% of the time but matches on every field only 12.7% of the time. We hold no inductor or bead datasheet for any of the 47 series, so the qualification report has to come from Walsin, not from us.

Send us your automotive bead or inductor part numbers with the case size and rated current you actually need, and we will come back with Walsin candidates field by field — blanks included — and tell you plainly that the qualification report is a separate request.

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Frequently asked questions

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