Disc Capacitor Body Code vs Capacitance: 47 of 7,507 Walsin Pairs Invert, and 5 of Them Are One Part Number

The disc capacitor body code does not rank capacitance. We compared every pair of capacitance values inside every series, dielectric and rating group in the 929-row Walsin export: 5,117 of 7,507 pairs rise with the code, 2,343 tie, and 47 invert, giving the higher capacitance a smaller body code. We have not seen this counted anywhere.

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Venatech Limited, an authorised Walsin distributor in Hong Kong, holds the ceramic disc capacitor parametric export published by Walsin Technology (Walsin): 929 rows, and no datasheet for any of them. This post is written from that one file. The last three digits of every disc part number carry a body or lead-pitch code, and we do not hold the document that defines it. Every part number below is real. What the code ranks, and where it stops ranking, is a question a footprint decision depends on.

Does a larger Walsin disc capacitor body code always mean more capacitance?

No. We parsed all 929 rows and read the final three digits of each part number as the body code. We then built 81 groups of parts sharing the same series, dielectric and rated voltage, and compared every pair of different capacitances inside each group. Of 7,507 pairs, 5,117 (68.2 percent) rise with the code, 2,343 (31.2 percent) tie, and 47 (0.6 percent) invert. An inversion is a pair where the higher capacitance carries the smaller code.

Outcome for a pair with different capacitance	Pairs	Share	Match / mismatch against “more capacitance, same or larger code”
Higher capacitance, larger body code	5,117	68.2%	Match
Higher capacitance, same body code	2,343	31.2%	Match (a tie, not a violation)
Higher capacitance, smaller body code	47	0.6%	Mismatch

The rule holds on 99.4 percent of pairs. That is why it is easy to believe and why the 47 are worth reading. 77 of the 81 groups hold two or more capacitance values; the other four hold one part’s worth of ladder and cannot invert. Ten of the 77 groups contain at least one inversion, and the 47 pairs touch 54 distinct part numbers.

Which ten groups hold the 47 inversions?

Two Class I ladders, three Class II ladders, one AS safety ladder, and four small-size safety groups that repeat one drop. We listed every inverted pair, then grouped them. The largest group is the 50 Vdc Class I SL ladder with 17 inverted pairs, and the second is the 100 Vdc Y5P ladder with 9.

Group (series, dielectric, rating)	Inverted pairs	Lower capacitance, body	Higher capacitance, body	Real part pair	Match / mismatch
Class I, SL, 50 Vdc	17	22 pF, 050	24 pF, 040	SL500220J050 and SL500240J040	Mismatch — more capacitance, one step smaller
Class I, SL, 500 Vdc	8	39 pF, 060	47 pF, 050	SL501390J060 and SL501470J050	Mismatch
Class II, Y5P, 100 Vdc	9	220 pF, 050	240 pF, 040	YP101221K050 and YP101241K040	Mismatch
Class II, Y5P, 2000 Vdc	2	470 pF, 080	560 pF, 060	YP202471K080 and YP202561K060	Mismatch — a two-step drop
Class II, Z5U, 1000 Vdc	2	3300 pF, 070	3600 pF, 060	ZU102332M070 and ZU102362M060	Mismatch
Safety AS, Y5U, X1 760 Vac / Y1 500 Vac	5	1000 pF column, 190	1500 pF, 090	YU0AS103M190 and YU0AS152M090	Mismatch — see below
Safety AH small size, Y5P, two ratings	2	220 pF, 060	330 pF, 050	YP0AH221K060 and YP0AH331K050	Mismatch
Safety AC small size, Y5P, two ratings	2	220 pF, 060	330 pF, 050	YP0AC221K060 and YP0AC331K050	Mismatch

The last two rows deserve a second look. The same step, 220 pF at 060 to 330 pF at 050, repeats in four separate safety groups: AH at X1 400 Vac with Y1 250 Vac and with Y1 400 Vac, and AC at X1 440 Vac with Y2 250 Vac and with Y2 300 Vac. A defect does not usually repeat four times in four ratings. A ladder built that way does.

Is the inversion one defect or several?

Three different things, and only one of them is a data defect. We separated the 47 pairs by what the lower-capacitance part looks like. In five groups the lower capacitance appears under two body codes; in five it is a clean one-step drop; and one part number, YU0AS103M190, supplies 5 of the 47 by itself.

Take the 50 Vdc SL ladder. 22 pF exists as SL500220J050 with code 050 and also at code 040, and 24 pF exists only at 040. The inverted pairs are the ones that compare the 050 version of 22 pF to everything at 040. The same shape appears at 39 pF in the 500 Vdc ladder, at 56 pF in the 50 Vdc ladder, at 220 pF in the 100 Vdc Y5P ladder and at 470 pF in the 2000 Vdc Y5P ladder. In all five, one capacitance is published at two body codes, and the pair counts are what that duplication produces against every higher step.

The other five are plain. ZU102332M070 at 3300 pF carries 070 and ZU102362M060 at 3600 pF carries 060. Nothing else in that group explains it. We hold no disc datasheet, so we cannot say whether the smaller code at the higher capacitance is a different dielectric thickness, a different disc or a transcription slip.

Pattern	Groups	Pairs	Step size of the drop	Match / mismatch against a monotone ladder
One capacitance published under two body codes	5 (including AS)	41	10 to 100	Mismatch — the duplicate creates the inversion
Clean step down at one capacitance	5	6	10	Mismatch — no duplicate to blame
All 47 together	10	47	40 of 47 are a single step of 10	Mismatch

Outside the AS series, no inversion is larger than two steps. 40 of the 42 non-AS pairs drop by exactly one step.

What does YU0AS103M190 contribute to the count?

Five of the 47, and the other 42 do not depend on it. We published earlier that this part number decodes to 10,000 pF while the Capacitance column says 1000 pF. If the column is wrong and the part is 10,000 pF, its body code 190 sits at the top of the AS ladder, all 5 of its inversions disappear, and 42 remain.

Part number	Capacitance column	Code decodes to	Body code	Match / mismatch against the AS Y5U ladder
YU0AS102M080	1000 pF	1000 pF	080	Match — smallest body, lowest capacitance
YU0AS152M090	1500 pF	1500 pF	090	Match
YU0AS472M140	4700 pF	4700 pF	140	Match — top of the published ladder
YU0AS103M190	1000 pF	10,000 pF	190	Mismatch — column and code disagree by 10 times; the body code sides with the code

The detail is in the capacitance code post. The point here is narrower. Whichever reading is right, the 42 other inversions stand, so the body code cannot be used as a capacitance ranking even after the one known defect is fixed.

What should a selector do with the body code?

Treat it as a label, not a ranking. The lead-spacing column is empty on all 929 rows, so the body code is the only size-like field the export gives you, and we have just shown that it fails as an ordering on 47 pairs in 10 groups. We showed earlier that on 350 parts the published fields do not fix the footprint at all. Three rules follow.

1. Never sort a disc ladder by body code and read the order as capacitance. In 10 of 77 groups it breaks.
2. Never assume two parts at the same capacitance share a body. In five groups one capacitance is published under two codes.
3. Confirm the dimension against Walsin’s own published catalogue before layout. We hold no disc datasheet, so every dimension reading from this export is a flag, not a specification.

None of the 929 disc capacitor part numbers appears in our ready-stock snapshot of 1,125 part numbers as at 23 September 2026, which lists ready stock in the MLCC, chip resistor and other lines. Ask us about disc availability directly. For the structure behind the other fields, see disc capacitor temperature coefficient codes, and for the family page see disc capacitors. Our free cross-reference tool states differences from your original part rather than hiding them behind a tick.

The short version

Walsin’s disc body code rises with capacitance on 5,117 of 7,507 pairs, ties on 2,343 and inverts on 47. The inversions sit in 10 of 77 groups and touch 54 part numbers. Five groups publish one capacitance under two body codes, five show a clean one-step drop, and YU0AS103M190 alone supplies 5 of the 47. Without it, 42 remain. The same 220 pF to 330 pF drop repeats in four safety groups. We hold no disc datasheet, so we will not tell you which reading is intended. We will show you the string the file holds. Qualification stays with you; confirm against both datasheets and qualify in your own circuit.

Send us the disc capacitor on your drawing and its hole spacing, and we will tell you what the export says about its body code and what it does not. And a question back: when you last sorted a disc ladder by size, did you check that the order held?

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Frequently asked questions

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