One 0603 Line, Six Walsin MLCC Series: 100 pF NP0 50 V Compared

0603, NP0, 100 pF, ±5%, 50 Vdc resolves to six Walsin part numbers in six different
series. Case size, dielectric, capacitance, tolerance and rated voltage are identical on all
six. Published length, width and thickness are identical too, except for one field: the two
soft-termination parts carry a length tolerance of ±0.20 mm against ±0.10 mm on the other four.

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Venatech Limited, an authorised Walsin distributor in Hong Kong, holds the full MLCC parametric
extract from Walsin Technology (Walsin) — 24,025 real parts across 16 series — and 26 of its
MLCC datasheets. Every part number below is real.

Which Walsin MLCC series carry 0603 100 pF NP0 50 V?

Six. One general purpose, one automotive, two RF-oriented, two soft termination. The part
numbers differ only in their prefix; the capacitance code 101, the tolerance code J and the
voltage code 500 are the same string in all six.

Part number	Series	Datasheet
0603N101J500	General Purpose	General Purpose
MT18N101J500	Automotive, AEC-Q200 (MT)	Automotive MT
HH18N101J500	High Q & Low ESR (HH)	High Q / Low ESR HH
RF18N101J500	Microwave (RF)	Microwave RF
SG18N101J500	Soft Termination, Cu-poly (SG)	Soft Termination SG
SH18N101J500	Soft Termination, Ag-poly (SH)	Soft Termination SH

This is not an unusual line. Counted across the extract, 26 distinct combinations of case
size, dielectric, capacitance, tolerance and rated voltage are served by six or more Walsin
series. The most crowded holds eight parts across seven series — 0603, NP0, 5.0 pF, ±0.25 pF,
50 Vdc. A five-field match does not identify a single MLCC, and on a line like this one it does
not even narrow you to a technology.

If the five selection fields match, what actually differs?

One published dimension, and everything that is not in the parametric export.

Field	0603N101J500	MT18N101J500	HH18N101J500	RF18N101J500	SG18N101J500	SH18N101J500	Match / mismatch
Case size	0603	0603	0603	0603	0603	0603	Match
Dielectric	NP0	NP0	NP0	NP0	NP0	NP0	Match
Capacitance	100 pF	100 pF	100 pF	100 pF	100 pF	100 pF	Match
Tolerance	±5%	±5%	±5%	±5%	±5%	±5%	Match
Rated voltage	50 Vdc	50 Vdc	50 Vdc	50 Vdc	50 Vdc	50 Vdc	Match
Length	1.60±0.10	1.60±0.10	1.60±0.10	1.60±0.10	1.60±0.20	1.60±0.20	Mismatch on the soft-term pair
Width	0.80±0.10	0.80±0.10	0.80±0.10	0.80±0.10	0.80±0.10	0.80±0.10	Match
Thickness	0.80±0.07	0.80±0.07	0.80±0.07	0.80±0.07	0.80±0.07	0.80±0.07	Match
AEC-Q200	—	Yes	—	—	—	—	Mismatch
Termination construction	Standard	Standard	Standard	Standard	Cu-polymer	Ag-polymer	Mismatch

Everything that would actually decide the choice — Q factor, ESR, board-bend survival,
qualification status — is in the datasheet and not in the export. The export’s eight populated
columns put six different parts in the same row of your BOM comparison and tell you nothing
about why six exist.

That is the single most useful thing to know about Walsin’s MLCC data: the parametric export
is a filter, not a selector. It will get you to the six. It will not pick one.

Why do the soft-termination parts have a wider length tolerance?

Because the polymer layer sits between the ceramic body and the plated termination, and it adds
length. Walsin publishes that as a doubled length tolerance.

The pattern holds across the whole 0603 shelf, not just this line. Of the 0603 MLCC parts that
publish a length:

Group	0603 parts with a published length	Length tolerance published
Soft termination — SH, SG and ST	287	198 at ±0.20 mm, 89 at ±0.30 mm. No part tighter than ±0.20
Everything else	4,385	3,712 at ±0.10 mm, 633 at +0.15/−0.10 mm, 40 at ±0.20 mm

So no soft-termination 0603 part in Walsin’s catalogue is published tighter than ±0.20 mm, and
4,345 of the 4,385 non-soft-termination parts are published at ±0.10 mm or the +0.15/−0.10 form.
Width and thickness are unaffected — the polymer adds length only.

The 40 exceptions are worth naming, because they are not soft-termination parts. All 40 are
General Purpose high-capacitance Class II parts — 10 µF and 22 µF X5R, and X6S parts — where the
thickness tolerance also widens to ±0.20 mm. Those are the thickest 0603 parts in the catalogue,
and they widen for a different reason.

For a land pattern this matters directly. Designing a 0603 pad to the ±0.10 mm part and then
substituting the SH or SG part doubles the length variation your fillet has to absorb. If the
reason you want the soft-termination part is board flex, do not then give it a pad that cannot
accommodate it.

How do you read the case size out of a Walsin MLCC part number?

Two different ways, depending on the series — and that is the trap.

13,062 of the 24,025 MLCC part numbers begin with the four-digit imperial case size instead
of a series prefix. Three series families do this: General Purpose (8,467 parts), Middle to
High Voltage 200 V–4 kV (4,095) and Big Sizes 1825/2220/2225 (500). That is 54.4% of the
catalogue — a majority. 0603N101J500 is one of them.

The other 10,963 parts carry a two-letter series prefix and then a two-digit case code.
SH18N101J500 is one of those: SH, then 18, then the electrical codes.

The two-digit code is the part’s own length and width in millimetres. Whole millimetres where
the dimension is 1 mm or more, tenths where it is under 1 mm:

Case size	Length × width (mm)	Code	Check
0402	1.0 × 0.5	15	1, then 5 tenths
0505	1.25 × 1.25	11	1, 1
0603	1.6 × 0.8	18	1, then 8 tenths
0805	2.0 × 1.25	21	2, 1
1111	2.8 × 2.8	22	2, 2
1206	3.2 × 1.6	31	3, 1
1210	3.2 × 2.5	32	3, 2
1808	4.5 × 2.0	42	4, 2
1812	4.5 × 3.2	43	4, 3
1825	4.5 × 6.3	46	4, 6
2211	5.7 × 2.8	52	5, 2
2220	5.7 × 5.0	55	5, 5
2225	5.7 × 6.3	56	5, 6

We checked this against every prefix-coded part that publishes a length and a width. It holds
on all 8,720 parts at 0402 and above, across all 13 case sizes, with zero exceptions.

It fails on both sizes below 0402. The 0201 case, 0.6 × 0.3 mm, codes as 03. The ultra-small
case, 0.4 × 0.2 mm, codes as 02. Those are the last two digits of the metric designation —
0603 metric and 0402 metric — a different convention for the two smallest sizes.

Why does the same two-digit code mean two different case sizes?

Because a script that reads characters three and four of any MLCC part number is reading a case
code on 10,963 parts and the back half of an imperial size designation on 13,062. Four codes
collide as a result:

Characters 3–4	Means this on a prefix-coded part	Means this on an imperial-fronted part	Rows carrying it
02	01005 (0.4 × 0.2 mm)	0402	2,008
03	0201 (0.6 × 0.3 mm)	0603	3,680
06	—	1206, and 0306	2,566
25	—	1825 and 2225	243

RF02N0R2A160 is an ultra-small part. 0402N150J201 is a 0402 part. Both read 02 at
positions three and four, and they differ by a factor of six in area. MT03N101J500 is a 0201
part and 0603N101J500 is a 0603 part; both read 03.

8,497 rows — 35.4% of the catalogue — sit in one of those ambiguous codes. The fix is to test
whether the first four characters are all digits before reading anything else. If they are, the
case size is those four characters. If they are not, the case code is characters three and four.

How do you pick one of the six?

Pick on the thing the export does not show you.

• No special requirement. 0603N101J500, General Purpose. The default, and the deepest
  shelf in the catalogue at 8,467 parts.
• Automotive programme. MT18N101J500. The MT series is Walsin’s AEC-Q200 qualified line;
  it is the only one of the six with a qualification claim. Ask for the report against the exact
  part number.
• RF matching, filtering or a resonant node. HH18N101J500 or RF18N101J500. Both are
  specified for Q and ESR where the general purpose part is not. Read both datasheets — the HH
  and RF series target different parts of the same problem.
• Board flex, edge connectors, large boards, press-fit assembly. SH18N101J500 or
  SG18N101J500. Ag-polymer and Cu-polymer terminations respectively. Budget the ±0.20 mm
  length tolerance into the pad.
• You are second-sourcing and want the closest fit to an incumbent part. None of the six is
  an answer on its own. Compare field by field against your incumbent’s datasheet, and expect at
  least one mismatch.

For how the soft-termination series differ from each other, see
Soft termination MLCC: SH, SG, ST and VT. For the
part-number structure in full, see
How to read a Walsin MLCC part number. The full
range is on the Walsin MLCC range page.

The short version

Six series answer 0603 100 pF NP0 50 V, and the five fields you normally tick cannot tell them
apart. The one dimension that differs is length tolerance on the soft-termination pair. Read the
first four characters of the part number before you read anything else — on 54.4% of the
catalogue they are the case size, and on the rest they are a series prefix plus a millimetre
dimension code.

Send us the specification and tell us what the part has to survive, and we will tell you which
of the series actually answers it, with the part number and the datasheet page. Or give us one
part number and ask us to cross it.

Faster than an email. The cross-reference tool takes a pasted list or a spreadsheet and returns Walsin ceramic capacitor candidates field by field, differences included. Ready stock shows what is physically in Hong Kong, so you can see straight away whether a line is a stock pull or a production slot.

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Frequently asked questions