Hello everyone, this is 52audio, very glad to see you again.
Today, the teardown product is the Redmi AirDots3 Pro earbuds.
Compared to the previous generation.
It has the better appearance and new features such as noise cancellation, wireless charging, etc.
Now let’s unpack it first.
This time, the packaging box has used the new Xiaomi logo.
The product logo of AirDots series is in the middle.
And then will be the product’s picture and name.
There are eight highlights on the back of the box: Bluetooth 5.2, active noise cancellation,
adaptive noise cancellation, game mode, dual device connection, long battery,
wireless charging, wired fast charging, and pop-up animation.
Here is the product’s specification.
Let’s take a closer look at it.
Model is TWSEJ01ZM.
It supports Bluetooth 5.2 and has Type-C port.
The maximum wired input of the charging case is 5V⎓0.5A 2.5W.
Wireless charging needs 5W+ wireless charger.
The wired charging time of the charging case is about 2.5 hours.
The overall battery life of the charging case is about 28 hours.
The battery life of the earbuds is about 6 hours.
The rated capacity of a single earbud is 35mAh.
The rated capacity of the charging case is 470mAh.
The manufacturer is ZMI Electronic Technology.
Next, let’s tear off the film and open the box.
Except for the earbuds, There is also a manual, a charging cable,
and three additional pairs of ear tips.
Let’s look at the earbuds.
The charging case adopts the common oval design.
The indicator light and Bluetooth pairing button are on the front.
The hinge and Redmi logo are on the back.
The Type-C port is at the bottom.
There is a metal-like ring around the port, which can protect the port and make it shinier.
Open the charging case and take out the earbuds.
There are two charging contacts in there, and there is also a Qi logo inside.
This product supports the wireless charging of the Qi protocol
The shape of the earbud is kinda special, and the backside is pretty like crystal.
You’ll see different lights at different angles.
This is an opening for noise cancellation microphone.
The pressure relief hole is equipped with a metal mesh cover to prevent foreign objects from entering.
There is also a call microphone opening at the bottom.
There is a small pressure relief hole at the bottom to balance the air pressure.
The overall weight of earbuds and charging case is about 52g (1.83oz).
The weight of the earbuds is about 10g (0.35oz), and single one is about 5g (0.18oz).
When connecting to a mobile phone, AirDots 3 Pro will have pop-up animation to
be quickly connected.
You can also see the remaining power of the earbuds through the pop-up animation.
AirDots 3 Pro supports three gestures: double-click, triple-click and long press.
And you can set two earbuds separately.
Only in this way, can we control it without our phones.
You can also personalize settings through the MIUI settings or the voice assistant，
to satisfy the different habits of different users.
Next, we start to tear it down.
Firstly, let’s tear down the charging case, heat this tiny gap, and then pry it little by little.
There is a LED light hole in the shell of the charging case.
At the bottom is the metal-like ring of the USB-C receptacle port.
And the PCB is fixed in here.
We need to remove the screws and cover.
Remove the other side.
There is a small charging board and multiple magnets at the bottom.
Remove the charging board, There are five magnets to attract the earbuds
and the charging case cover.
This is a small board for charging the earbuds.
There are four pogo pins for charging the earbuds.
An LED light is on the back, and a black rubber light guide is on the outside.
A Hall element is used to sense the magnetic field’s changes when the charging case cover
is opened and closed.
And then, it will inform the MCU of the charging case and tell the earbuds
to connect or disconnect from the paired device.
That is the Hall effect.
A small thermistor is on the cable connected to the motherboard
and used to detect battery temperature.
The wireless charging coil and battery are connected to the motherboard.
There is a shielding sticker under the coil.
The battery capacity is 470mAh.
The battery circuit is connected to the motherboard through a cable.
Let’s look at the motherboard.
There is a physical button on it.
The bottom of the USB-C receptacle port is engraved with the ZMI LOGO
And Type-C port is soldered on the motherboard.
This is low-power MCU chip from SiNH Micro SS881Q-W, which integrated wireless charging
and RX controller and linear charging unit and power management unit
for battery charge & discharge management and overall control.
This is overvoltage and overcurrent protection IC from etasolution ETA7014.
This is lithium battery protection IC from XySemi.
This is wireless charging receiver chip from NuVolta NU1680C,
integrated the synchronous rectifier.
That makes it have high efficiency, low cost and can adjust the output voltage, track the
battery voltage for reducing the power consumption.
And next, let’s start to tear down the earbuds.
Remove the touch back panel of earbuds.
We can see another layer under the panel,
which make it have different lights in different angle.
A plastic plate is under the touch panel,
which fixes the touch sensor and Bluetooth antenna.
The motherboard unit of the earbuds can be seen under the plastic plate.
Take out the motherboard.
But we can’t continue to disassemble, because of the isolation layer underneath.
The speaker in the front of the earbuds is welded on the small “U” board.
Two BTB connectors on the small board are connected to the in-ear detection sensor and
the cable from the motherboard.
The charging contacts of the earbuds are also soldered on this small board.
Remove the speaker.
The noise cancellation microphone and in-ear detection sensor are in same cable.
The battery is fixed by plastic.
This cable connects to the motherboard Take out the battery and connection cable.
The battery capacity is 35mAh, also from Eve Energy.
This is a MEMS bone conduction sensor from STMicroelectronics.
It can detect whether keywords are spoken by user and reduce false triggers caused by
keywords from other people in the environment.
Let’s take a look at the motherboard.
Here are two elastic plates connecting the touch sensor and the antenna.
This is the microphone for noise cancellation.
This one is for the phone call.
The master control chip adopts Airoha AB1565AM.
It is Airoha’s next-generation Bluetooth audio technology, supports Bluetooth 5.2 and
can support LE audio in the future.
It also has a built-in CM4 processor and Tensilica HiFi mini DSP
and integrates lithium battery charge controller and power management,
which makes it has ultra-low power consumption,
stable Bluetooth connection, clear sound quality and Hybrid active noise cancellation.
This is the capacitive touch MCU of the modern microcontroller
A96T346, used for touch control.
Okay, that’s it for our today’s teardown of Redmi AirDots3 Pro Noise Cancellation Earbuds.
Its inner components are pretty nice.
And it’s amazing to be sold at such a low price.
This is 52 audio.
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I’ll catch you guys the next time.