Walsin RF Case Size: 17 Sizes, 8 Functions, and Only 30 of 136 Grid Cells Hold a Part

We built the walsin rf case size grid nobody publishes: 17 distinct case sizes against 8 RF functions is 136 cells, and 30 hold a part. No case size reaches more than 4 of the 8 functions. 10 of the 17 exist in exactly one function.

Venatech Limited, an authorised Walsin distributor in Hong Kong, parsed the Size column of all 15 files in Walsin Technology (Walsin)’s RF product export — 457 part numbers across 8 functions — and built the function-by-case-size grid a front-end designer needs before placing a single footprint. It does not exist anywhere else we have looked. Every part number below is real. We hold zero datasheets for the RF line, so there is no land pattern in our library for any of these parts; Walsin’s own site is the only dimensional source we can point you at.

How many case sizes does Walsin’s RF line actually offer?

Seventeen distinct strings, and they are not all case sizes. We read all 457 Size values and found 11 written as a bare numeric case code — 1608, 2012, 1005, 2520, 3225, 1109, 605, 1411, 1814, 1510, 2109 — and 6 written as millimetre dimensions: 2.0×2.0, 1.1×0.7, 1.5×1.1, 1.1×1.1, 1.0×1.0 and 2.4×2.0. Two notations, one column, no key. Here is the whole grid.

Count the right-hand column before anything else. 30 of 136 cells hold a part and 106 are empty. We have not seen this grid published anywhere, and we built it because a question we keep being asked — “can I keep one footprint across the front end?” — has no published answer.

Which case size appears in the most RF functions?

1608, on 161 of the 457 parts and in 4 of the 8 functions: 65 filters, 57 multiplexers, 24 baluns and 15 couplers. Nothing else reaches four. 2012 and 1005 reach three each but both skip the coupler. 1109 reaches three only because it is the sole size for both acoustic filter families. That makes 1608 the one footprint on which a filter, a multiplexer, a balun and a coupler can all be laid out.

Four real 1608 parts, one per function, with the fields the export publishes:

The second row is the one to take away. RFDIP1606L168M1U carries 1606 inside its own part number and 1608 in the Size column. So does RFCPL1810B2450T, which says 1810 and sits at 1608. We read both fields and we will not pick one for you. A land pattern derived from a part number instead of from the Size column will be wrong on those parts, and there is no datasheet in our library to settle it.

Which RF functions offer only one case size?

One of the eight, and a second one is empty. The SAW filter file holds 3 parts and all 3 are case size 1109 — SF11091582GC2T, SF11092350B4004T and SF11092595B4108T. There is no second footprint and no second part. The antenna switch module file is worse: it carries 12 column headers and zero rows, so it offers no case size at all.

The rest run from two upwards. Coupler offers 2 (1608 and 605). BAW offers 3 across 5 parts, so DA18141747B3E1T at 1814 and BA14112593B41E1T at 1411 are each the only part at their size in their function. Balun offers 4, multiplexer 5, antenna switch 6 across 9 parts. Filter offers 9, the widest in the line, and still skips every millimetre-dimensioned size.

If your layout needs an alternative footprint on a SAW filter, this line does not have one, and we would rather say that than send you a selector that returns nothing. For how thin the band-by-band shelves run underneath this, see Walsin RF: balun, filter, coupler and multiplexer.

Why does the antenna switch file share zero case sizes with the other seven?

Because it is the only one of the eight written in millimetres. All 9 antenna switch parts carry a Size value like 2.0x2.0 or 1.1x0.7, and none of those 6 strings appears in any other RF file. The intersection between the antenna switch file’s size vocabulary and the other seven files’ is empty. That is not a near-miss; it is zero of 6 against zero of 11.

This is the same class of problem as a case size written two ways in one catalogue — see passive component case sizes, imperial and metric. Here the two notations never meet. Sort the RF line by board area and you get a list in which 605 falls below 1005 and 2.0x2.0 below both, because it is text.

What happens to a layout that assumes one footprint across the RF chain?

It runs out of parts, and the measurement says where. Of the 11 four-digit codes, only 1608 reaches four functions. 10 of the 17 sizes exist in exactly one function: 3225, 2109, 1814, 1510 and all 6 millimetre strings. Three of those ten hold a single part each — AMTIP2109ATM0T63 at 2109, DA18141747B3E1T at 1814 and RFBPB1510060A0T at 1510.

So a front end that wants a filter, a diplexer, a balun and a coupler on one footprint has exactly one choice here, and it is 1608. Add an acoustic filter and there is none, because 1109 carries no balun, no coupler and no multiplexer. Add an antenna switch and there is none twice over, because the switch file does not use case codes at all.

That is the grid. It is not an argument that the line is thin — 457 parts across 8 functions is a real catalogue — it is an argument that the catalogue’s own Size column will not tell you this and we have not found anyone who has counted it.

How do you check a Walsin RF footprint before you commit the board?

Start from the part number and work outward, because the export cannot close the loop on its own. The Size column is the only dimensional field Walsin publishes for these 457 parts — there is no length, width, thickness or land pattern column anywhere in the 38 column names across the 15 files, and 0 of our 451 datasheet pages cover an RF part.

1. Ask us for the datasheet by part number. We hold 28 Walsin datasheets, 451 pages, and zero cover an RF part. We will request the one you need in writing. Nothing has been requested yet and we will not tell you otherwise.
2. Treat the Size column as the authority and the part number as a hint. RFDIP1606L168M1U and RFCPL1810B2450T both disagree with themselves, and we found no third field to arbitrate.
3. Cross the passives around the RF block in one pass. Paste up to 500 part numbers or drop your Excel or CSV into the free cross-reference tool, filter by commercial or automotive grade, and read every stated difference rather than a claimed match. Those lines we do hold datasheets for.

Check what is physically in Hong Kong on ready stock: 1,125 part numbers as at 23 September 2026, a dated snapshot and not a live feed. The full range sits on the Walsin RF page. Our line runs from Hong Kong, Shenzhen, Singapore and Jiangmen, with Chengdu in preparation, and nowhere else.

The short version

17 case size strings, 8 RF functions, 136 grid cells, 30 populated. 1608 is the only size reaching 4 functions and covers 161 of 457 parts. 10 of the 17 exist in exactly one function and 3 of those hold a single part. The SAW file offers one case size on 3 parts; the antenna switch module file offers none on zero rows. The 9 antenna switches use millimetres and share nothing with the other seven files. Two part numbers disagree with their own Size column. We hold zero datasheets for this line, so every dimension here is a spreadsheet string. Qualification stays with you, and so does the land pattern — our job is to get you the document that settles it.

Send us the RF block off your schematic and we will return the case sizes actually available for each function, which ones share a footprint, and what we will have to ask Walsin for. And a question back: your front-end layout assumed one footprint across the chain — which of the 106 empty cells did it land in?

Frequently asked questions