In March 2023, Nothing officially released a new iterative product – Nothing Ear (2). The appearance continues the family-style transparent shell design, and the waterproof performance has been improved – the earbuds have reached IP54 for sweat and dust resistance, and the charging case also support IP55 protection. In terms of functional configuration, it is equipped with an 11.6mm dynamic drive unit, upgraded LHDC 5.0 transmission protocol, supports 24bit/192kHz high-resolution audio, and has passed Hi-Res audio certification.
Nothing Ear (2) has upgraded the personalized noise cancellation function, with 3-level of noise cancellation modes, which can be adaptively adjusted according to the environmental noise, and the maximum noise cancellation depth can reach 40dB. Support personalized ANC function, you can customize the exclusive noise cancellation effect according to the shape of the ear through the Nothing X APP, bringing a more accurate noise cancellation experience. It also supports the transparent mode of environmental sound enhancement, and the noise cancellation function of the 3-microphone call, providing users with a full-scenario noise cancellation experience.
In other respects, Nothing Ear (2) supports low-latency mode (with Nothing Phone) to meet the needs of game scenarios. Support pressure-sensitive control, in-ear detection and multi-point connection. When the ANC is turned off, the total battery life is increased to 36 hours, and the single battery life is up to 6 hours. It supports fast charging and 2.5W (Qi certified) wireless charging function. Let’s take a look at the detailed teardown report of Nothing Ear (2).
01/ Nothing Ear (2) charging case teardown
Remove the bottom cover of the charging case. The internal components of the charging case fit the chamber design and make perfect use of the internal space. A wireless charging receiving coil and a small circuit board are fixed on the inside of the cover.
The wireless charging receiving coil circuit is set on the magnetic shielding sticker. The wires connect to a small circuit board, which then connects to the main board through contacts.
Remove the screws and take out the motherboard and battery unit.
The circuit on the motherboard side of the charging case.
The circuit on the other side of the charging case motherboard.
The TVS tube with silk screen P24 004 is used for input overvoltage protection.
Silkscreen N6S k MOS tube for input control. TPS SY5320 overvoltage and overcurrent protection IC is a highly integrated protection IC with input undervoltage and overvoltage protection, lithium battery front-end overvoltage protection, abnormal load current protection, and overtemperature protection. Support 28V input withstand voltage, overvoltage shutdown protection is less than 1uS, support high-precision battery overvoltage protection function.
Bluetooth pairing function button.
Connect to the BTB connector of the FPC.
Connect the metal dome connector of the wireless charging receiving coil.
TPS SY8809 bluetooth headset charging compartment solution. The chip integrates a charging module and a discharging module. The charging module adopts the NVDC architecture, and the charging current of the battery terminal can be adjusted by I2C. The output voltage I2C of the discharge module can be adjusted, and it integrates two output current limiting switches, provides independent load presence detection and load insertion detection, and supports output current detection. The chip integrates NTC protection function to charge and discharge the battery more safely.
SY8809 integrates standard I2C interface and interrupt signal, which facilitates the communication between the chip and MCU, and controls the charging and discharging functions. SY8809 integrates a communication port, which can realize high-speed communication from the MCU to the earphone end, which is very suitable for the design of the bluetooth headset charging compartment. The high level of integration greatly simplifies the peripheral circuits and components, providing an easy-to-use solution for the application of the TWS charging compartment. The package used by SY8809 is QFN4x4-24.
The peripheral power inductor of the power management chip.
Chipsea CS32F031K8U6 MCU microcontroller. The CS32F031 series microcontrollers use a high-performance 32-bit ARM® Cortex®-M0 core, embedded up to 64K Bytes flash and 8K Bytes SRAM, with a maximum operating frequency of 48MHz. The chip provides standard communication interfaces (I2C, SPI/I2S and USART), 1 channel 12bit ADC, 7 16bit timers, 1 32bit timer, 1 enhanced control PWM timer. The working temperature range is -40℃~105℃, and the working voltage range is 2V~5.5V.
COPO CP2022 is a single-chip, advanced, flexible, secondary-side wireless charging transmission chip that can provide up to 3W of power for portable applications. It has the advantages of high integration, high efficiency, and low power consumption, and complies with the Qi V1.2.4 standard.
Silkscreen MKY IC.
Take out the FPC inside the charging case.
The circuit on the FPC side.
The other side of the FPC is connected to the main board through the BTB connector.
Pogo Pin connector for charging earbuds.
Two LED indicators of different colors, and the peripheral hood prevents light leakage.
The Hall element of the AR3B1 silk screen is used to sense the magnetic field change when the charging case cover is turned on/off, and then inform the charging case MCU to control the pairing or disconnection of the earbuds with the connected device.
The Pogo Pin connector that connects the FPC to the motherboard.
The charging case built-in lithium battery model: VDL 831536PF4, rated voltage: 3.85V, capacity: 480mAh/1.867Wh, from VDL.
There is a charging limit voltage on the back silk screen: 4.4V.
The circuit on one side of the battery protection board is equipped with an integrated lithium battery protection IC and a thermistor for monitoring the battery temperature.
iCM M1112-DAE is a single-cell lithium battery protection IC with built-in MOSFET. Built-in high-precision voltage detection circuit and delay circuit, by detecting the voltage and current of the battery, it can protect the battery from overcharge, overdischarge and overcurrent. Protection circuit for single-cell Li-ion/Li-polymer rechargeable batteries.
02/ Nothing Ear (2) Earbuds Teardown
Enter the earbuds dismantling part, and open the earbud cavity along the earbud head parting line.
The internal structure of the front cavity is provided with a bracket to fix the battery unit.
The internal structure of the rear cavity, the FPC is connected to the internal motherboard of the earbud stem, and the in-ear detection sensor is attached to the cavity wall.
Take off the back cover of the earbud stem, and take out the motherboard unit.
The inner structure of the cover is provided with a black bracket to fix the bluetooth antenna.
The circuit on one side of the earbud motherboard.
The circuit on the other side of the earbud motherboard.
The BTB connector that connects the internal components of the front cavity.
TPS SY5501 power management PMIC is a chip specially designed for TWS earbuds, providing a perfect solution for charging and isolation communication. The chip integrates linear charge management, discharge protection, single-wire two-way data communication and I2C communication interface, which is convenient for users to realize earbuds charge and discharge management and protocol communication.
The maximum charging current of SY5501 can be adjusted by an external resistor, and it also supports constant current charging ICC and floating charging voltage VFLOAT gear I2C adjustment. The chip integrates NTC detection and protection functions to more safely charge and discharge the battery. SY5501 has battery discharge protection and shipmode functions, which can meet the low power consumption requirements of the headset system. The chip integrates private control commands, and the charging case can send commands through the VIN to control the SY5501, realizing the power on/off and reset operations of the earbuds main control.
Silkscreen NS U’s IC.
The metal piece that connects the bluetooth antenna.
Connect the BTB connector of the pressure-sensitive control board.
The MEMS microphone of Leidiao G047 is used for voice pickup.
AWINIC AW86862 pressure sensing IC, with pressure sensing signal acquisition, amplification and processing functions. Integrates 1 I2C communication module, 1 system control module, 1 power management module and 1 AFE module (including 2 analog input differential channels and multiplexers, 2-stage PGA, 11-bit offset calibration DAC, 14 bit ADC and intelligent pressing logic processing module). The size of AW86862 is as small as 1.41mm×1.41mm, which is very suitable for the small space of TWS.
BES BES2600YP bluetooth audio SoC, Bluetooth + noise cancellation + in-ear detection three-in-one single-chip solution. Support dual-mode Bluetooth 5.3 and multi-point connection, internally integrate dual-core ARM STAR-MC1 CPU and ultra-low power consumption Sensor Hub subsystem, with powerful application processing capabilities. Support open adaptive noise cancellation and AI noise cancellation. Support auxiliary listening function and spatial audio. Support functions such as voice wake-up and interaction.
The crystal oscillator that provides the clock for the bluetooth chip.
Laser carving G051 MEMS microphone. It is a feed-forward noise cancellation microphone, which is used for the noise cancellation function to pick up external environmental noise.
The FPC of the internal components of the earbud head.
The BTB connector that connects the FPC to the motherboard.
In-ear detection sensor for detecting wearing status.
AWINIC AW93105DNR in-ear detection IC is a 5-channel low-power, high-precision capacitive in-ear detection and touch controller. Each channel can be independently configured as a capacitance detection channel and a reference channel, which can be used for in-ear detection, touch button detection and sliding functions in TWS earbuds. The package size is small and can be placed on the FPC of the in-ear detection, thus saving the space of the motherboard.
AW93105DNR adopts advanced self-capacitance technology, and with the help of AWINIC’s in-ear detection algorithm and sliding algorithm, it can accurately identify operations such as putting on and taking off TWS earbuds, clicking, double-clicking, and sliding. It is used for in-ear detection function in this product.
Silkscreen 2Z hz lithium battery protection IC.
Open the cover of the sound cavity to see the structure of the internal speaker unit.
Open the speaker, and the end of the FPC is equipped with an in-ear detection sensor and a noise cancellation microphone for feedback.
On the front of the speaker, the diaphragm is protected by a metal cover.
On the back of the speaker, there is a tuning hole in the center, which is protected by a silk screen.
After actual measurement, the size of the speaker is about 11mm.
The earbud has a built-in steel shell button battery, model: 1033S1, nominal voltage: 3.85V, rated capacity: 33mAh 0.127Wh, from VDL.
In-ear detection sensor. Two in-ear detection for more precise control.
Laser carving R130 MEMS microphone. It is a feed-back noise cancellation microphone for picking up ambient noise from inside the ear canal, from RAYKING.
Internal structure of earbud stem cavity. The FPC with pressure-sensitive buttons and charging contacts is fixed, and the end is the sealing structure of the call microphone.
A pressure sensitive sensor fixed on the cavity wall.
The BTB connector on the FPC is used to connect with the motherboard.
Take out the FPC of the pressure sensor. The metal connector on the FPC is used to connect to the charging case for charging.
Nothing Ear (2) true wireless noise cancellation earbuds all components.
Nothing Ear (2) adopts a very brand characteristic transparent shell design. The square charging case with rounded corners has been optimized in structure, with a splicing design of a transparent shell and a white cavity. The texture of the transparent material is more crystal clear, and the white cavity adopts a frosted texture, and the dot matrix concave-convex texture decoration is canceled. The earbuds continue the stem-shaped in-ear design of Nothing Ear (1), and the earbud stem transparent shell allows you to clearly see the internal circuit structure.
In terms of internal structure, the internal space is perfectly utilized, and in the case of upgraded configuration, it has a lighter size than the previous generation. In terms of main configuration, the charging case has a built-in VDL 480mAh lithium battery and is equipped with iCM CM1112-DAE lithium battery protection IC. Wired charging uses the TPS SY8809 bluetooth headset charging compartment solution. Wireless charging uses COPO CP2022 wireless charging transmission chip. It is also equipped with Chipsea CS32F031K8U6 MCU microcontroller and TPS SY5320 overvoltage and overcurrent protection IC.
In terms of the main configuration inside the earbuds, it is equipped with an 11.6mm dynamic drive unit and built-in three MEMS microphones for pickup. The capacity of the steel shell button battery has been increased to 33mAh. The main control chip is upgraded to BES BES2600YP bluetooth audio SoC. TPS SY5501 power management PMIC, AWINIC AW86862 pressure sensing IC and AW93105DNR in-ear detection IC are also used.