Sony LinkBuds Teardown

The Sony LinkBuds were announced only last month and we already have a teardown by 52Audio. Check their article out for the full teardown which features a lot more detail than I will be posting. Photos courtesy of 52Audio.

So beginning with the case PCB, we can see Sony has decided to solder on the battery cables like in the WF-C500. While not a major issue, replacing the battery would require more work and tools than in the WF-1000XM4, which has its battery attached to the board with a connector.

There is a connector in the top left, but this is for the extra PCB which signals to the headset to either connect/disconnect to the paired device when the lid is opened/closed. The USB type-C port is not centered on the board since to the left is a reset button.

The other side of the PCB has the main controller chip and the charging pins. The main chip is the K32 L2B microcontroller; more information about it can be found here. Interesting to see the model code printed on the board, YY2953, rather than the model name, WF-L900 like in other models.

Comparing the internal battery, we have a type 621733 lithium ion, with a capacity of 300mAh/1.11Wh. If this battery looks familiar, that is because it is the exact same battery that is found in the WF-C500 charging case. For the rest of the case teardown check the source.

Now moving onto the earbuds themselves, both halves in the driver unit and main body are glued together.  As seen below, the black substance does not surround the entire opening, so this is probably not for IPX4 resistance but to hold the pieces together (in addition to glue). There is also no mesh on the holes so best to keep any dirt and water away from them. The little holes do face the ear canal, so it is possible that the hole could get clogged up with dirt and ear wax.

Opening up the main body, we have a ribbon cable connecting the cover to the rest of the unit. So be careful when opening this part so as not to rip/damage the cable.

On the inside we have the battery which is held inside the earbuds with a plastic surround. This is probably to keep the battery in place. Unfortunately the consequence of this is that the battery looks to be smaller than in other models.

The battery is a Zenipower brand again but a different model, Z32H. The capacity is 3.85V 0.12Wh, which is around 31 mAh. Looking at the other Sony earbuds, the WF-C500 is around 70 mAh and the WF-1000XM4 is around 75 mAh.