A TDK MLCC alternative for an automotive or RF-grade line is found inside the qualified
series of Walsin Technology (Walsin) — MT and ST for AEC-Q200, HH, RF and UF for
microwave — never by matching five electrical fields alone. 93.5% of Walsin’s AEC-Q200
part numbers share their size, dielectric, capacitance, tolerance and voltage with at
least one non-qualified part. Venatech holds no TDK or Taiyo Yuden lifecycle data.
Venatech Limited, an authorised Walsin distributor in Hong Kong, writes this from Walsin’s
24,025-row MLCC parametric export and the linked series datasheets. Every part number below
is real and checkable in that export. This post does not name a TDK or Taiyo Yuden part
number and does not reproduce either manufacturer’s specifications. We hold no such list for
either manufacturer, so nothing here states that any of their parts is discontinued,
obsolete, end-of-life or constrained.
What is a TDK MLCC alternative at automotive and RF series level?
A candidate drawn from the Walsin series that actually carries the qualification or the RF
grade your TDK or Taiyo Yuden line claims — not just a part that happens to share the same
case size, dielectric and value. TDK’s automotive ceramic lines and Taiyo Yuden’s RF and
microwave ranges both sell on a property a five-field electrical match cannot see: a
qualification scope or a frequency-grade dielectric behaviour documented in the series
datasheet, not in a parametric column.
Cross on five fields alone and Walsin’s export will hand you several candidates that match
electrically and differ completely on the property you actually needed.
Which Walsin series cover automotive-qualified and RF-grade MLCC?
Five series carry the qualification or RF claim; three more sit alongside them on the same
electrical ground without carrying it.
| Walsin MLCC series | Parts held | Case sizes | Qualification / grade |
|---|---|---|---|
| Automotive Caps Qualified to AEC-Q200 (MT) | 2,176 | 0201–1210 | AEC-Q200 per series datasheet |
| Automotive Soft Term, AEC-Q200 (ST) | 118 | 0402–2220 | AEC-Q200, soft termination |
| Automotive Caps Without AEC-Q200 (MG) | 788 | 0201–1812 | Series title states not certified |
| High Q & Low ESR Caps (HH) | 1,709 | 0201–0805 | NP0, microwave / low-ESR grade |
| Microwave Caps (RF series) | 3,615 | 01R5–1111 | NP0 / X8G, microwave grade |
| Ultra Microwave Caps (UF) | 285 | 0201, 0402 | NP0, narrow tolerance microwave |
| General Purpose Caps | 8,467 | 0201–1812, plus 0306 | No qualification or RF claim |
| Microwave RT (automotive NP0) | 0 in export | 0402, 0603 per datasheet | AEC-Q200, datasheet only |
Sources: MT,
ST,
MG,
HH,
Microwave RF,
General Purpose,
Microwave RT.
RT is Walsin’s own automotive-qualified microwave series by name and datasheet scope, and it
is one of four MLCC series already identified in Venatech’s own catalogue audit as returning
zero rows in the parametric export — datasheet only, no downloadable part list. If a TDK or
Taiyo Yuden automotive RF line crosses electrically into RT’s documented range, the candidate
has to be requested from Walsin by name; it will not appear in any exported search.
Does a five-field match tell you whether a Walsin candidate is AEC-Q200 qualified?
No, and the gap is wide enough to change the outcome of most crosses. Size, dielectric,
capacitance, tolerance and rated voltage are the fields every part-number decoder reads
first, and they say nothing about qualification.
Unique to Venatech’s data. Of the 2,291 Walsin MLCC part numbers in the two AEC-Q200
qualified series (MT and ST), 2,142 — 93.5% — share their five-field signature (case
size, dielectric, capacitance, tolerance, rated voltage) with at least one part in a
non-qualified series. The non-qualified series they collide with most often are General
Purpose (1,872 shared signatures), HH (629), Soft Termination SH (600), Microwave RF (552)
and Middle to High Voltage (308). A cross tool or a script that matches on those five
fields alone will return a qualified and a non-qualified candidate with equal confidence,
because nothing in the five fields tells them apart.
That means the qualification decision cannot be automated from the parametric export. It has
to be read from the series identity and the series datasheet, every time, before a part is
quoted as AEC-Q200 qualified.
What does this look like on a real 0201 NP0 0.2 pF 50 V line?
Five real Walsin parts, identical on every field a quick filter checks, and only one of the
five is AEC-Q200 qualified.
| Walsin part number | Series | AEC-Q200 | L × W × T (mm) | Your TDK/Taiyo Yuden part — fill in from its datasheet | Match / mismatch |
|---|---|---|---|---|---|
MT03N0R2B500 |
Automotive MT | Qualified per series datasheet | 0.60±0.03 × 0.30±0.03 × 0.30±0.03 | ||
MG03N0R2B500 |
Automotive MG | Series title: not certified | 0.60±0.03 × 0.30±0.03 × 0.30±0.03 | ||
0201N0R2B500 |
General Purpose | Not claimed | 0.60±0.03 × 0.30±0.03 × 0.30±0.03 | ||
HH03N0R2B500 |
High Q & Low ESR | Not claimed | 0.60±0.03 × 0.30±0.03 × 0.30±0.03 | ||
RF03N0R2B500 |
Microwave RF | Not claimed | 0.60±0.03 × 0.30±0.03 × 0.30±0.03 |
Sources: MT,
MG,
General Purpose,
HH,
Microwave RF.
Case size, dielectric, capacitance, tolerance, voltage and even the published dimensions are
identical across all five rows. If your incumbent line is specified as AEC-Q200 qualified,
MT03N0R2B500 is the only one of the five that carries the claim in its own series
datasheet. The other four are not wrong parts — HH and RF are built for microwave behaviour
that MT does not specifically claim, and a design that only needs the electrical value and
not the automotive qualification may prefer one of them on cost or lead-time grounds. The
point is that nothing in the five matched fields tells you which is which.
What happened to Walsin’s dedicated automotive-RF series, RT?
It exists on paper and nowhere in the data Venatech can query. Walsin’s own series index
lists “Microwave RT, AEC-Q200” covering 0402 and 0603 at NP0, 0.1–100 pF, 25–50 V — exactly
the ground a TDK or Taiyo Yuden automotive RF capacitor would need to cross into. The
parametric export returns zero rows for it.
That is a known gap in Walsin’s public data, not a statement about the part’s availability.
The practical consequence for a cross is that an automotive RF line should be checked against
the RT datasheet by name, in addition to the MT and HH candidates that do show up in a
parametric search. Relying on the export alone would miss RT entirely.
How do I find out whether my TDK or Taiyo Yuden line is still available?
Ask the manufacturer, or your TDK or Taiyo Yuden distributor, in writing, for the exact part
number on your BOM. We hold no such list, so nothing here states that any TDK or Taiyo Yuden
part is discontinued, obsolete, end-of-life or constrained; only the manufacturer can tell
you that.
We will run the Walsin side of the comparison in parallel — qualification claim, dimensions,
and the series the candidate actually sits in — so a second source is ready to qualify
whether or not you decide to use it.
The short version
Treat qualification and RF grade as series-level properties, never as something a five-field
match can confirm. 93.5% of Walsin’s AEC-Q200 part numbers sit on the same electrical ground
as a non-qualified part, so the series name and its datasheet are the only reliable source.
Check RT by name if your line is automotive-grade RF — it will not appear in a parametric
export. Confirm status with the manufacturer and qualify any candidate yourself.
Send your TDK or Taiyo Yuden specification and tell us whether AEC-Q200 or RF grade is
required. We will return the Walsin candidates with the claim stated series by series, and a
column left for your part.
Frequently asked questions
Can a five-field MLCC match confirm AEC-Q200 qualification?
No. Case size, dielectric, capacitance, tolerance and rated voltage say nothing about qualification. 93.5% of Walsin’s AEC-Q200 MLCC part numbers (MT and ST) share that five-field signature with at least one non-qualified part, so qualification has to be read from the series name and its datasheet separately.
Which Walsin series is AEC-Q200 qualified?
MT (2,176 parts, 0201–1210) and ST (118 parts, 0402–2220, soft termination) carry the qualification in their own series datasheets. MG covers similar electrical ground but its series title states it is without AEC-Q200 certification.
Does Walsin have an automotive-qualified RF or microwave MLCC series?
Yes by name — RT, “Microwave RT, AEC-Q200”, covering 0402 and 0603 at NP0. It returns zero rows in Walsin’s parametric export, so it has to be requested by name against its datasheet rather than found through a parametric search.
Is a specific TDK or Taiyo Yuden MLCC line discontinued?
We hold no such list, so we cannot tell you. There is no TDK or Taiyo Yuden lifecycle data, affected-part list or allocation information on file here. Ask the manufacturer or your distributor in writing for the status of the exact part number on your BOM.
Why do HH and RF series parts show up on the same signature as an automotive MT part?
Because NP0 dielectric behaviour at a given case size, value, tolerance and voltage can be electrically identical across several Walsin series built for different purposes. HH and RF are built for low ESR and microwave behaviour respectively; MT is built for automotive qualification. The electrical fields overlap; the series purpose does not.
What do you need from me to start a TDK or Taiyo Yuden cross?
Case size, dielectric, capacitance, tolerance, rated voltage, and whether AEC-Q200 qualification or RF-grade performance is a hard requirement. If only a part number is available, send it and we will work back to the published specification.
How do you handle a Walsin series with no parametric data, like RT?
We say so and quote from the series datasheet directly rather than from an export that does not contain it. Any specification taken from RT in that situation is flagged for written confirmation from Walsin before it is used in a design.
Next step
Send the specification and tell us whether AEC-Q200 qualification or RF-grade performance is
required — that single fact decides which Walsin series the candidate has to come from.
Venatech Limited, an authorised Walsin distributor in Hong Kong, will return the Walsin
candidates with the qualification claim and dimensions stated per series, and a column left
for your part. Confirm the status of your current line with TDK or Taiyo Yuden, and qualify
any candidate in your own circuit before release.
Send your BOM to Venatech · Browse the
Walsin MLCC range · Read
AEC-Q200 MLCC: MT vs MG series and
High-Q low-ESR MLCC for RF.
Cross it yourself. The cross-reference tool takes a single part number or a whole BOM column and returns the Walsin candidates with every field that differs stated plainly — qualification stays with you. Ready stock shows what is held in Hong Kong today, with an RFQ against any line.