The Walsin MLCC datasheet soldering profile is a picture on 11 of the 12 approval sheets we opened. Nine sheets end on the same soldering page, word for word, with two sentences and two captions as the only text. Only the 1825, 2220 and 2225 sheet prints the profile parameters as numbers.
Venatech Limited, an authorised Walsin distributor in Hong Kong, holds 28 datasheets from Walsin Technology (Walsin), 451 pages in all. This post is written from the first 12 series approval sheets in the MLCC folder, 175 pages, which we read page by page with pdftotext and pdfimages. We compared the last pages of the sheets with each other after removing the footer and the figure numbers. Every part number below is real and sits in the series its sheet describes. The question is the one a process engineer asks before a first article: where in the PDF are the reflow numbers?
How are the 175 pages of Walsin’s 12 MLCC approval sheets divided?
Into three blocks, and the middle one is the smallest. We located the “Reliability test conditions and requirements” heading on every sheet and the “Appendixes” block that closes it. 88 pages come before the reliability heading, 52 are reliability tests, and 35 are appendix: 50.3, 29.7 and 20.0 percent of 175. Every sheet is between 8 and 29 pages, and the “Page N of M” footer total equals the real page count on all 12.
| Sheet | Pages | Before reliability | Reliability tests | Appendix | A real part | Match / mismatch against the General Purpose appendix |
|---|---|---|---|---|---|---|
01_General_Purpose |
21 | 11 | 7 (12 to 18) | 3 (19 to 21) | 0603B104K500 |
reference |
02_Ultra_Small_01005 |
8 | 4 | 2 | 2 (7, 8) | 01R5B101K100 |
Mismatch — same topics folded onto 2 pages, reflow figure only |
03_Large_Size_1825_2220_2225 |
10 | 5 | 2 | 3 (8 to 10) | 1825B224K631 |
Mismatch — tape and reel, then application notes |
04_Middle_and_High_Voltage |
13 | 8 | 2 | 3 | 0805B101K251 |
Match |
05_Surface_Coating_Type |
9 | 4 | 2 | 3 | no series of its own | Match |
06_Microwave_RF |
19 | 14 | 2 | 3 | RF03N0R1A250 |
Match |
07_Microwave_High_Reliability_RH |
13 | 8 | 2 | 3 | no export rows | Match |
08_Microwave_Narrow_Tolerance_UF |
9 | 4 | 2 | 3 | UF03N0R1A101 |
Mismatch — the wave-soldering profile is dropped |
09_Microwave_Automotive_RT |
10 | 4 | 3 | 3 | no export rows | Match |
10_High_Q_Low_ESR_HH |
11 | 6 | 2 | 3 | HH15N0R2A500 |
Match |
11_Automotive_MT |
29 | 13 | 13 | 3 | MT15N0R5C500 |
Match |
12_Soft_Term_Automotive_ST |
23 | 7 | 13 | 3 | ST18B473K500 |
Match |
| Total | 175 | 88 | 52 | 35 |
The 12 sheets are 175 pages and we have read all of them. The reliability tables are 2 pages on 8 sheets, 3 on the RT sheet, 7 on the General Purpose sheet and 13 on each of the MT and ST sheets.
Is the soldering page the same on every sheet?
On nine of the ten sheets that end on it, yes, word for word. We stripped the footer, removed the figure numbers and collapsed the line breaks, then compared the last page of each sheet with the General Purpose page. Nine pages are character-for-character identical, 538 characters each: sheets 01, 04, 05, 06, 07, 09, 10, 11 and 12. The tenth, the UF sheet, matches except that it drops the wave-soldering profile and its caption. Sheet 02 prints the same text on page 8 beside the construction and storage notes, with the reflow figure only, and sheet 03 has no such page.
We have not seen this counted anywhere: 175 pages, 35 of them appendix, and the soldering page repeats nine times as one page. The text reads, in full, that the lead-free termination MLCCs suit lead-free and lead-containing solder paste, that “increasing soldering time, temperature and concentration of N2 within oven are recommended” for an optimised joint, and then two figure captions. It carries no peak temperature, no time and no ramp rate; the only digit is the 2 in “N2”.
The 23 September 2026 ready stock snapshot holds 786 part numbers in the 9 export series these sheets describe. 782 of them sit in a series whose sheet carries the identical page, and 4 do not: 3 on the large-size sheet and 1 in the UF series. A snapshot is a dated list, not a live feed.
Where is the recommended soldering profile, in the text or in a picture?
In a picture on 11 of 12 sheets. We ran pdftotext and pdfimages on the soldering page of each sheet. On the 11 sheets that print a recommended-profile caption, the page lists 5 or 6 image objects, and the soldering block of its text layer holds the caption and no temperature, time or ramp rate. The only digit in it is the 2 in “N2”. On the General Purpose sheet, page 21 lists 6 image objects, including one of 639 by 425 pixels and one of 836 by 420. The caption reads “Recommended reflow soldering profile for SMT process with SnAgCu series solder paste”; the profile it names is not in the text.
The exception is 03_Large_Size_1825_2220_2225.pdf, page 9, which prints the parameters as a table citing IPC/JEDEC J-STD-020D.
| Profile feature | 03_Large_Size_1825_2220_2225, page 9, as printed |
The other 11 sheets | Match / mismatch |
|---|---|---|---|
| Preheat and soak, minimum and maximum | 150 °C and 200 °C | picture only | Mismatch — no number in the text |
| Time from minimum to maximum soak | 60 to 120 seconds | picture only | Mismatch |
| Ramp-up rate | 3 °C per second maximum | picture only | Mismatch |
| Liquidus temperature and time above it | 217 °C; 60 to 150 seconds | picture only | Mismatch |
| Peak package body temperature | classification temperature 260 °C | picture only | Mismatch |
| Ramp-down rate and time from 25 °C to peak | 6 °C per second maximum; 8 minutes maximum | picture only | Mismatch |
This matters for anyone who searches Walsin’s PDFs for a temperature. We counted what pdftotext returns from the soldering block of the other 11 sheets: the digit 2 in “N2” and nothing else once the figure number is removed. A script, or a reader using a text search, finds the 260 °C on the large-size sheet and finds nothing on the other eleven. For the question of what the sheets say in text about hand soldering, see our hand-soldering and cleaning post.
Does a figure number identify the figure?
No. The profile figures carry different numbers on different sheets, and two numbers are reused for the other profile. We read the captions on all 12 sheets. The reflow profile is Fig. 5 on four sheets, Fig. 6 on four, Fig. 18, Fig. 19 and Fig. 25 on one each: five numbers for one picture. The wave profile is Fig. 7, 6, 26, 19 and 20, also five numbers. Fig. 6 is the reflow profile on four sheets and the wave profile on two; Fig. 19 is the wave profile on the RH sheet and the reflow profile on the HH sheet.
| Sheet | Reflow profile caption | Wave profile caption | Match / mismatch against the General Purpose numbering |
|---|---|---|---|
01_General_Purpose, 04, 05, 09 |
Fig. 6 | Fig. 7 | reference |
02_Ultra_Small_01005, 08_Microwave_Narrow_Tolerance_UF |
Fig. 5 | none | Mismatch — number and no wave profile |
06_Microwave_RF |
Fig. 25 | Fig. 26 | Mismatch |
07_Microwave_High_Reliability_RH |
Fig. 18 | Fig. 19 | Mismatch |
10_High_Q_Low_ESR_HH |
Fig. 19 | Fig. 20 | Mismatch — Fig. 19 is the wave profile on sheet 07 |
11_Automotive_MT, 12_Soft_Term_Automotive_ST |
Fig. 5 | Fig. 6 | Mismatch — Fig. 6 is the reflow profile on sheet 01 |
A purchase specification that says “see Fig. 6 of the Walsin approval sheet” points to a reflow profile on four sheets and a wave profile on two. The numbers are consecutive within a sheet and do not travel between sheets. Cite the caption text and the page, as we suggested for section numbers in our post on datasheet section numbers.
How long is the reliability table on each sheet?
Two pages on eight of the 12 sheets, and thirteen on the two longest. The 52 reliability pages break down as 8 sheets at 2 pages, the RT sheet at 3, the General Purpose sheet at 7, and the MT and ST sheets at 13 each. The MT, ST and RT sheets each cite five AEC-Q200 test numbers, yet they run 13, 13 and 3 pages, and MT and ST together hold 26 of the 52 pages, half of them. We did not read why. We are not saying the short tables test less; we are saying a reader who wants the soldering heat or the board-flex row opens page 14 of a 29-page MT sheet and page 5 or 6 of a nine-page one.
The capacitor range sits on the MLCC page, and the AEC-Q200 wording is “compliant”, as Walsin writes it. Request the qualification report for the exact part number.
What should a supplier-approval file attach for the soldering profile?
The soldering page and the page that carries the profile picture, cited by caption, and a written statement from Walsin of the profile values for your series. We hold 28 Walsin datasheets, 451 pages, and we will send the sheet for your part number. Our free cross-reference tool tells you which series a candidate belongs to; the profile that applies to it is the one on that series’ sheet, and the parameters are yours to confirm.
Qualification stays with you. A profile on a datasheet is a recommendation from the manufacturer; your oven, your board and your paste decide the profile you run, and your own test results decide whether the part passes. Confirm against both datasheets and qualify in your own circuit.
The short version
The 12 Walsin MLCC approval sheets are 175 pages: 88 before the reliability heading, 52 of tests and 35 of appendix. Nine sheets end on one soldering page, 538 characters, word for word; the UF sheet matches minus the wave profile. On 11 sheets the recommended reflow profile is a picture with a caption and no number in the text; only the 1825, 2220 and 2225 sheet prints it as a table, with a 260 °C classification temperature. The reflow profile is five different figure numbers and Fig. 6 means reflow on four sheets and wave soldering on two. We will not tell you a profile suits your part. We will tell you which page it is on. Confirm against both datasheets and qualify in your own circuit.
Send us the part numbers on your BOM and we will tell you which sheet, and which page, carries the soldering guidance for each. And a question back: if your process specification quotes a figure number from a Walsin sheet, which of the five did it mean?
Frequently asked questions
Is the Walsin MLCC reflow profile in the datasheet text?
On one sheet of 12. The large-size sheet prints the profile parameters as a table on page 9, with a 260 °C classification temperature. On the other 11 the recommended reflow profile is a picture with a caption, and the text layer of the page carries no temperature, time or ramp rate.
Do all Walsin MLCC sheets carry the same soldering page?
Nine of them do, word for word: General Purpose, Middle and High Voltage, Surface Coating, Microwave RF, RH, RT, High Q HH, MT and ST. The UF sheet drops the wave profile. The Ultra-small sheet folds it onto page 8, and the large-size sheet has application notes instead.
How many pages of a Walsin MLCC sheet are appendix?
35 of 175 across the 12 sheets, 20.0 percent: 3 pages on 10 sheets, 2 on the Ultra-small sheet and 3 on the large-size sheet. They cover tape and reel, a customer-label example, constructions, storage and handling, and recommended soldering conditions.
Is Fig. 6 in a Walsin datasheet the reflow profile?
It depends on the sheet. Fig. 6 is the reflow profile on the General Purpose, Middle and High Voltage, Surface Coating and RT sheets, and the wave profile on the MT and ST sheets. Cite the caption text and the page instead of the number.
Which Walsin sheets have a wave-soldering profile?
Nine of the 12: the General Purpose, Middle and High Voltage, Surface Coating, RF, RH, RT, HH, MT and ST sheets. The Ultra-small and UF sheets print a reflow profile only, and the large-size sheet prints application notes in place of a profile page.
Can I search the datasheet PDFs for the peak temperature?
Only on one sheet. A text search for 260 °C finds the large-size sheet’s table. On the soldering block of the other 11 sheets the text layer holds no temperature, because the profile is an image, so the search returns nothing.
Where do I get the profile values for my series?
From Walsin. We hold 28 datasheets, 451 pages, and send the sheet for your part number on request. We have not transcribed numbers from the profile pictures, so ask for the profile in text or table form and confirm it against your own process.