Sony LinkBuds S FCC Teardown

In the main LinkBuds S post, Sony provided us a glimpse at the new System in Package (SiP) setup in the new earbuds, but we did not have any shots off the other components. So while we wait for a full teardown, the FCC filing does provide us with a teaser of what we can expect.

This will be a rather short analysis since the FCC filing does not provide that much. The first 2 photos show the LinkBuds S with the main cover taken off, revealing the contacts for the wireless antenna and touch sensor.

1. Microphone mesh 2. Contacts for wireless antenna/touch sensor

The photo is not of the best quality but the 2 contacts do correspond with 2 contacts on the main board/SiP which I will show latter. The right side photo shows how thin and compact Sony has made the new LinkBuds S. The battery is definitely not a CP1254 since it is too thin, and second all of Varta's coin cell batteries are 3.7V, while the LinkBuds S use a 3.85V battery, like the WF-1000XM4. So I suspect Sony is using a Zenipower battery here as well. 

    

Looking at the left side assembly, we see a lot of stuff and the packaging seems quite efficient. Almost as if Sony took some ideas from origami, since a lot of the ribbon cables are folding onto themselves for tighter packaging.

1. Feedforward microphone
2. Feedback microphone
3. Contacts for the driver
4. Proximity sensor

Turning the assembly over, we do not have much else apart from the charging pin contacts (3 arrows right) and the wireless antenna/touch sensor contacts (2 arrows left), which I talked about earlier.

I initially though the right earbud would be identical with the exact same parts but a mirrored image. This is not the case, since there is an extra piece at the end of the ribbon cable near the SiP.

This extra piece can actually be see on one press photo from Sony below, but this does not really help in identifying what it is for.

While this is just a rendering of the earbuds, this extra part can be seen here as pointed out by the arrow. This extra piece looks to have some components on it, but the quality of the photo is too poor to make them out. Perhaps the full teardown by 52Audio will reveal what this extra piece is for.

Looking at the System in Package, we have 2 sides. The side facing the interior has the main Bluetooth SoC, the Mediatek M2822M, an oscillator crystal, and lots of tiny other components. There does appear to be some little chip beside the SoC, but not sure what that is for. This entire side is covered by resin according to the FCC documents and it looks like the photo on the right side below.

Flipping this over, we have the 2 contacts for the wireless antenna/touch sensor, a ribbon connection strip which connects the SiP to the rest of the internal components. and 2 more unknown chips. Perhaps these will be labelled in the production version teardown.

One interesting piece of information from the FCC documents is a date on the SiP photos. The pictures of the SiP were taken back in 2021, on July 7th. This was a pre-production model according to the other documents. Looking back in my posts, the first appearance of the YY2950 was back in November on Korea's FCC and then a month later on the FCC. So almost 4 months earlier Sony already had pre-production models ready in the lab. 

So perhaps any upcoming WF-1000XM5 model could be testing in prototype form at Sony already. The WF-1000XM4 passed through the FCC in April 2021, with an appearance on Korea's FCC in mid March 2021. This means, it might still be a while before we see anything with regards to the WF-1000XM5, perhaps later on in the year in Q4 or in Q1 2023. But I am certain Sony has working prototype's at their labs. 

    

 If the new LinkBuds S show us anything, it is that Sony is willing to minimize the internal packaging of their earbuds to make smaller earbuds. While I expect a similar internal design and packaging of the WF-1000XM5, I do hope Sony uses the extra room to perhaps add a larger driver, or additional armature drivers, if not maybe keep a larger battery for longer use.

That is it for now, I am looking forward to a full teardown, to see the battery capacity and how it is all put together. If anyone notices anything interesting in these photos which I failed to mention, leave a comment below.