AIP, MIP, WIP and 33 More: How to Read a Walsin Inductor Part Number

A Walsin inductor part number prefix decodes to exactly one series in 33 of 36 cases,
measured across all 5,410 real parts in Venatech’s extract. AIP is 71 parts, one series.
MIP is 25 parts across three sub-series. WIP is 53 parts across four. Three prefixes break
the one-to-one rule: two are shared between series, and one — CSMM — feeds a series that is
not named after it at all.

Venatech Limited, an authorised Walsin distributor in Hong Kong, built this decode table from
Walsin Technology (Walsin)’s full inductor parametric export — 5,411 rows, one of which
(Test123999) is a QA test row excluded from every count below. The real total is 5,410 parts
across 36 distinct part-number prefixes. Every part number named in this post is real and
checked against that extract.

What does the AIP prefix mean on a Walsin inductor?

AIP is Walsin’s shielded power inductor line, 71 parts, one series, sized 4442 to 7265. The
series field in the export reads “AIP Seires” — Walsin’s own typo for “Series,” carried
straight through the parametric export. It does not affect the part number, only the series
label a filter would display.

What do MIP and WIP decode to?

MIP is 25 parts split across three sub-series by a suffix letter: MIP Series (13 parts,
plain), MIP-P Series (8 parts), MIP-H Series (4 parts). WIP is 53 parts split across four:
WIP Series (22), WIP_S Series (19), WIP_A Series (8), WIP_Y Series (4). In both cases
the four-letter prefix alone tells you the family; a suffix letter or underscore code after it
tells you which sub-series.

Real examples at the plain MIP Series level: MIP20121R0MBE and MIP20122R2MBE, both 2012
case size. Both sit in the same series and the same case size; the digits after the letters are
the inductance code, not part of the prefix.

Does every inductor prefix map to exactly one series?

Yes for 33 of the 36 prefixes found in the export. The full table:

MCI, MCB, MHC, WIP, WLBD, WLPH and MIP each cover more than one series, but every
sub-series carries that same prefix at the front — a reader can always tell the family from the
first few characters, then the sub-series from a suffix letter or an automotive marker in the
series name.

Which prefix is shared by two different series?

Two prefix pairs name a single combined series between them rather than each keeping its own:
MCB and MHC both feed into MCB / MHC Automotive Series (150 parts, on top of their own
MCB-S/MCB-H/MCB-B and MHC-S/MHC-P lines), and WFI and WLFW both feed into a single
WLFW/WFI Series (197 parts: 109 WFI plus 88 WLFW). Real examples:

A prefix match on the first letters of the series name works for four of these six real parts
and fails for two. Filtering a parts list on “series starts with the part-number prefix” will
silently drop every WFI and MCB row that belongs to a combined series.

Is there a part number that does not decode at all?

One does not decode as expected. 16 part numbers begin CSMM, not CSME, and all 16 are
filed under CSME Series — the series name used by the other 73 parts that do begin CSME.
Both groups sit at the same 4040 case size, with the same hyphenated part-number format (a base
code, a dash, then an inductance suffix). Reading the first four letters of a CSMM part
number and expecting a series called “CSMM” will not find it; the series is CSME Series, 89
parts total, 73 of them starting CSME and 16 starting CSMM.

Can I trust the prefix alone to identify a series?

Mostly, not always. 33 of 36 prefixes map cleanly — read the first 3–5 letters and you know the
family. Three prefixes need more care: MCB and MHC both also feed a shared automotive
series, WFI and WLFW both feed a shared series named for only one of them, and CSMM feeds
a series named for a different four letters entirely. A script built on “first four characters
= series key” will mis-sort 16 CSMM parts and mis-handle every WFI row.

For the part numbers that will not paste or sort cleanly for other reasons, see
why Walsin part numbers do not paste into your BOM.
For how the same prefixes split between multilayer and wirewound construction, see
multilayer vs wirewound chip inductors. Browse
the full Walsin inductor range.

The short version

36 prefixes, 5,410 real parts, 33 prefixes that map one-to-one once you read the suffix letter.
Watch three exceptions: MCB/MHC share an automotive series, WFI/WLFW share a series
named for only one of them, and CSMM feeds a series called CSME. None of the 36 has a
Walsin datasheet PDF on file with Venatech.

Send us a list of your inductor part numbers and we will tell you, prefix by prefix, which
series each one belongs to and whether we hold any specification data for it. Or ask us to
cross a single part.

Two things you can do without waiting for a reply. Cross your part — paste a single number or drop in an Excel or CSV of the whole line, and each result names what matches and what does not. And ready stock lists the inductor part numbers held in Hong Kong, with an RFQ against any of them.

Frequently asked questions