TDK and Murata Chip Inductor Cross Reference to Walsin: Zero of 5,410 Rows Publish All Nine Decision Fields, Checked for Italy

A TDK and Murata chip inductor cross reference to Walsin cannot be closed on published data alone. We counted all 5,410 real rows of Walsin_Inductor_ALL.xlsx field by field: not one row publishes all nine electrical fields the decision needs. 4,328 publish eight, and the one they miss is saturation current.

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Venatech Limited, an authorised Walsin distributor in Hong Kong, holds all 203 Walsin Technology (Walsin) parametric export files, 28 Walsin datasheets running to 451 pages, and zero inductor datasheets. We hold no TDK or Murata document of any kind, and no affected-part list from any manufacturer. So this post names the competitors only at family level, puts Walsin’s own measured data in the tables, and leaves a column for the part you already have. Every Walsin part number below is real, with the QA test row Test123999 excluded.

Which fields does a chip inductor cross actually have to be decided on?

Nine electrical fields, and four more the export has no column for at all. We opened Walsin_Inductor_ALL.xlsx and counted, column by column, how many of the 5,410 real rows carry a usable value in each. Four fields are complete on every row. Saturation current reaches 146. Three of the fields an Italian appliance or motor-drive programme will be asked about at supplier approval do not exist as columns.

Field a chip inductor cross is decided on	Column in the export	Rows of 5,410 publishing a usable value
Footprint, length by width	Size L*W (mm)	5,410
Height	Thickness (mm)	5,410
DC resistance	RDC	5,410
Rated current	Rated Current	5,410
Inductance	Inductance plus Unit	4,769 — 641 bead rows carry an ohm value instead
Inductance tolerance	Tolerance	5,387
Self-resonant frequency	SRF(min)	4,409
Q factor	Q Min	4,328
Saturation current	Saturation Current	146
Impedance at 100 MHz	Impedance (100MHz[Ω])	609
Shielded or unshielded construction	none	0
Operating temperature range	none	0
AEC-Q200 qualification status	none	0

Four of those thirteen lines are the whole reason a cross goes wrong. For most candidates the decisive field is simply absent.

How many of Walsin’s 5,410 inductor rows publish all nine electrical decision fields?

None. We tested every row against all nine at once: zero of 5,410. 4,328 rows publish eight of the nine; on 4,324 of those the missing field is saturation current and on 4 it is Q. Below that, 218 publish seven, 232 publish six, 609 publish five and 23 publish four. We have not seen this counted anywhere.

Fields published, of nine	Rows	Which field is missing
9	0	—
8	4,328	saturation current on 4,324 rows, Q on 4
7	218	combinations of Q, SRF and saturation current
6	232	Q, SRF and saturation current
5	609	bead rows: no inductance, no Q, no SRF, no saturation current
4	23	bead rows that also carry no usable tolerance

We then checked whether the two halves of the decision ever meet on one row. Of the 146 rows that publish a saturation current, zero also publish a Q factor and only 4 also publish a self-resonant frequency. The power-selection fields and the RF-selection fields are mutually exclusive in this file.

What transfers when you cross a multilayer RF chip inductor family?

The geometry and the value transfer. The Q figure does not, and the resonance figure cannot be compared as printed. If you are crossing from TDK’s multilayer chip inductor families (the MLK and MLG family lines) or Murata’s multilayer and thin-film RF families (the LQG, LQP and LQW family lines), the swap is decided on Q at your operating frequency and on SRF — and we measured that Walsin publishes a Q value with no stated test frequency anywhere in the file, and an SRF(min) column with no stated unit anywhere in it.

One position — 10 nH, ±2 percent, 0402 — field by field across two real Walsin rows, with a column for the part you already have.

Decision field	WLCW1005Z0G10NTB	MCI1005HQ10NGHBP	Your incumbent part	Match / mismatch between the two Walsin rows
Series	WLCW	MCI	______	—
Inductance	10 nH	10 nH	______	Match
Tolerance	±2%	±2%	______	Match
Footprint L × W	1.0 × 0.5 mm	1.0 × 0.5 mm	______	Match
Thickness	0.66 mm	0.50 mm	______	Mismatch — 0.16 mm, 32% taller
Q Min	21	8	______	Mismatch — 2.6x apart, and no test frequency is published for either
SRF(min)	3.9	3400	______	Mismatch — the column carries no unit, so 3.9 and 3400 cannot be read against each other
RDC	0.2Ω	0.3Ω	______	Mismatch — 50% higher
Rated current	480mA	0.5A	______	Match in magnitude, mismatch in how it is written
Saturation current	not published	not published	______	Mismatch with the decision itself — neither row can settle it

We will not tell you either of those is equivalent to your incumbent. We will show you exactly where they differ, and on this position they differ on four of nine fields before your part even enters the table.

What does not transfer when you cross a shielded power inductor family?

The saturation behaviour does not transfer, and the construction is not stated. Crossing from TDK’s metal-composite and shielded power families (the TFM, SPM and VLS family lines) or Murata’s metal-alloy and multilayer power families (the DFE and LQM family lines), a buck or motor-drive swap is decided on saturation current and the inductance-versus-current curve. We counted: 146 of 5,410 rows publish a saturation current, and no column publishes a curve, a shield type or a core material.

Decision field	MIP20122R2MBE	WIP322512A-2R2ML	CSME0418D-2R2M	Your incumbent part	Match / mismatch across the three Walsin rows
Inductance	2.2 µH	2.2 µH	2.2 µH	______	Match
Tolerance	±20%	±20%	±30%	______	Mismatch — CSME is a grade looser
Footprint L × W	2.0 × 1.25 mm	3.2 × 2.5 mm	4.0 × 4.0 mm	______	Mismatch — 6.4x board area from smallest to largest
Thickness	0.90 mm	1.10 mm	1.85 mm	______	Mismatch — 2.1x
RDC as published	0.17Ω	60mΩ	42Ω	______	Mismatch — and three different unit conventions, which we have published separately
Rated current	900mA	3A	2.2A	______	Mismatch — 3.3x
Saturation current	not published	not published	3A	______	Mismatch — one of three rows publishes it
Shield or core construction	no column	no column	no column	______	Mismatch with the decision — the file cannot answer it

Three real Walsin rows at the identical inductance, and the only field all three agree on is the inductance itself.

Does Walsin’s own part number code always agree with its inductance column?

Not quite. We decoded the inductance code out of every part number where the code and the Unit column use the same unit — 3,542 of 5,410 rows — and compared it against the Inductance column. 4 rows disagree. Two physical parts are involved, each appearing twice because two sister series carry the same part under different prefixes.

Part number	Code in the part number	Inductance column	RDC	Rated current	Match / mismatch
WLPH201610MR47PP	R47 — 0.47 µH	4.0 µH	33mΩ	3.5A	Mismatch — code and column differ by 8.5x
WIP201610P-R47ML	R47 — 0.47 µH	4.0 µH	33mΩ	3.5A	Mismatch — the same row under a second series name
WQPH201610M1R5PS	1R5 — 1.5 µH	2.2 µH	0.086Ω	2.4A	Mismatch — and the sibling WQPH201610M2R2PS also reads 2.2 µH on a different DCR
WPA201610S-1R5ML	1R5 — 1.5 µH	2.2 µH	0.086Ω	2.4A	Mismatch — the same row under a second series name

A separate 10 rows in the WQQC series are not errors but rounding: the code carries two digits where the column carries three, so WQQC0806Z0J12NPB reads 12 in its code and 12.3 nH in its column. We have not seen either count published anywhere. The consequence for a cross: decode the incumbent’s code, decode ours, then check ours against the column too.

What must a buyer ask for, because the published data cannot settle it?

Five documents, and none of them is in the export. The file has 14 columns and none carries operating temperature, RoHS status, lifecycle, lead time or qualification status — a catalogue-wide absence we have published. For an inductor cross specifically, this is the list to put in writing.

1. The inductance-versus-current curve for the exact part number. 146 of 5,410 rows publish a saturation current and none publishes the curve behind it. The four MIP-H rows whose saturation current sits below their rated current, which we have already published, are why the curve matters more than either number.
2. The Q test frequency. Q Min is published on 4,328 rows and the file names only one frequency anywhere, in the impedance column header.
3. The unit on SRF(min). The column has none, and values span four orders of magnitude.
4. The construction — shielded, unshielded, metal composite or multilayer. No column states it.
5. The AEC-Q200 qualification report for the exact part number, if the board is automotive. Walsin’s own word is compliant, never certified, and Venatech makes no qualification claim of its own.

What should an Italian buyer do next, and what will Venatech not claim?

Venatech has no Italian entity and no stock in Italy. Our locations are Hong Kong, Shenzhen, Singapore and Jiangmen, with Chengdu in preparation, and shipment is from Hong Kong. What travels to Milan or Bologna is the data work and the goods: lot and date-code traceability, a certificate of conformity per shipment on request, and original sealed Walsin packaging, from Unit 207, 2/F, Sun Ling Plaza, 30 On Kui Street, Fanling, N.T., Hong Kong, (852) 2628 4777.

1. Paste the incumbent list, do not retype it. Up to 500 part numbers, or drop your Excel or CSV, into the free cross-reference tool. It is matched against Walsin’s published catalogue, and every difference from your original is stated rather than hidden.
2. Send the nine fields with the list. We will tell you which of the nine the export answers for each line and which it cannot — and on the evidence above, at least one will always be missing.
3. Check the shelf before you commit a build slot. Ready stock is a dated snapshot as at 23 September 2026, not a live feed, and inductors are 0.04% of it.

For the saturation-current gap in detail, see chip inductor cross reference: 146 of 5,410 publish saturation current, and for the four inverted rows, rated current versus saturation current in chip inductors. The whole line is on the Walsin inductor page.

The short version

A TDK and Murata chip inductor cross reference to Walsin is decided on nine electrical fields, and we counted that zero of 5,410 Walsin rows publish all nine. 4,328 publish eight; the missing field is saturation current on 4,324 of them. The 146 rows that do publish saturation current publish no Q at all and an SRF on only 4. Four more fields — shielding, operating temperature, AEC-Q200 status and lifecycle — have no column anywhere, and Walsin’s own inductance code disagrees with its inductance column on 4 rows. We hold zero inductor datasheets, no TDK or Murata document, and no affected-part list from any manufacturer, and we say so rather than let you assume otherwise. Qualification stays with you.

Send us your inductor lines with the nine fields filled in as far as you can, and we will come back with the Walsin candidates, the fields the export answers, the fields it cannot, and the exact questions we will put to Walsin in writing on your behalf. One question back: on your last inductor swap, which of the nine fields did you actually verify, and which did you assume?

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Frequently asked questions

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