Huawei FreeBuds 5 is equipped with a ultra-magnetic drive unit, dual magnetic circuit architecture – the low-frequency sensitivity is increased by 30% compared with the previous generation, and the low-frequency can be extended to 16Hz. Newly added bass sound pressure Turbo technology to further enhance the low-frequency effect. Support ultra-wideband real-time listening optimization to create delicate sound quality. Supports L2HC and LDAC audio decoding, can better restore rich sound details, and has passed Hi-Res certification. Audio Vivid spatial audio (fixed) is also supported for an immersive listening experience.
Semi-in-ear comfortable noise cancellation 3.0 supports three-microphone hybrid noise cancellation. With the ear canal adaptive algorithm, it can intelligently adjust the noise cancellation mode according to the user’s ear shape, the wearing status of the earbuds, and by identifying external environmental noise. Support AI call noise cancellation, through three-microphone hybrid noise cancellation and deep neural network algorithm, accurately pick up human voice, weaken environmental noise, and provide clear calls.
We have previously teardown Huawei products including: Huawei FreeBuds 4E, Huawei FreeBuds 4, Huawei FreeBuds Pro 2, Huawei FreeBuds Pro, Huawei Watch Buds, Huawei Watch GT Cyber, Huawei Watch GT3, Huawei Band 7 and Huawei Sound Joy. Let’s take a look at the detailed teardown report of this product.
$130 – Huawei FreeBuds 5 Review
01/ Huawei FreeBuds 5 Charging Case Teardown
Teardown the charging case shell and take out the charging cockpit structure.
The frame under the charging cockpit is fixed by screws, and various components are arranged on the frame.
The cover plate structure on the other side has an indicator light FPC attached to it. The Hall element at the bottom of the charging cockpit is connected to the main board through FPC.
The main board structure is fixed on the frame by positioning columns. The FPC is connected to the main board through the BTB connector, and the battery wires are welded on the main board for protection.
Open the connector, remove the screws, and separate the charging cockpit.
The charging contacts, Hall elements, indicator lights, and function buttons at the bottom of the charging cockpit are connected to the same circuit.
One side structure of the frame to fix the motherboard.
The other side of the frame holds the battery.
Remove the motherboard and battery from the frame.
The charging case has a built-in lithium-ion polymer battery pack, model: HB751834EFW-11, rated capacity: 505mAh 1.95Wh, nominal voltage: 3.87V, charging limit voltage: 4.45V, made in China.
Tear off the external insulation protection, silk screen information on the internal cell, model: 731832, from ATL.
The battery protection board circuit, the components are protected by black hard glue, and the detailed information cannot be obtained.
The circuits on one side of the motherboard.
The circuit on the other side of the motherboard.
Silk screen H22 H IC.
Silk screen 2F JD IC.
Silkscreen RZR DZB IC.
Connect to the BTB connector of the FPC.
Silkscreen A25 IC.
Nations N32G4FR MCU microcontroller. The N32G4FR series uses a 32-bit ARM Cortex-M4 core with a maximum operating frequency of 144MHz. Support floating-point operations and DSP instructions, built-in cryptographic algorithm hardware acceleration engine, integrated up to 512KB encrypted Flash memory, 144KB SRAM, which can be used to safely store fingerprint information. Support mainstream semiconductor fingerprint and optical fingerprint sensor. Supports up to 18 channels of capacitive touch keys, and integrates rich U(S)ART, I2C, SPI, QSPI, USB, ADC, DAC, SDIO and other common peripheral interfaces.
The crystal oscillator that provides the clock for the MCU.
Southchip SC8753 is a high-efficiency direct charging chip specially designed for TWS charging case. The component is paired with a Southchip SC7289 linear charging chip (headphones) for charging or bi-directional UART communication via a 2-contact connection.
SC8753 adopts Buck Boost topology, integrates MOSFET, has low quiescent current and light load PFM mode. It provides excellent power efficiency, current and voltage regulation whether the charging voltage is above, below or equal to the input voltage. It supports an input voltage range of 2.7V to 5.5V and an output voltage range of 3.0V to 5.2V. SC8753 supports CC/CV loop, and the charging parameters are controlled by SC7289 in the earbuds during trickle charging and CV charging stages. In the CC charging stage, SC7289 is fully turned on, SC8753 controls the charging current in constant current mode, and supports a continuous charging current up to 750mA, with ultra-low heat dissipation and high charging safety. In communication mode, charging is suspended and the 2-wire power connection switches to a UART data connection. With two-way UART communication over the power line, the charging case and earbuds can exchange data and request fast charging.
The charging case has a built-in buck-boost charging circuit, and the output voltage can be adjusted to follow the battery voltage of the earbuds to realize direct charging of the earbuds. In the charging case, the voltage conversion efficiency is improved, and the loss of earbuds linear charging is also eliminated, which prevents earbuds from heating and improves the overall battery life.
Another Southchip SC8753 buck-boost chip, the two chips charge earbuds respectively.
Renesas DA9168 battery charge management chip, built-in dual independent LDO and reverse boost function. Support for the USB On-The-Go (USB-OTG) standard has very low quiescent current consumption and a very compact footprint, making it ideal for a wide range of space-conscious battery-powered consumer applications.
Silkscreen 4W IC.
Silkscreen B1 IC.
Remove the FPC at the bottom of the charging cockpit.
FPC side circuit.
The circuit on the other side of the FPC.
The BTB connector that connects the FPC to the motherboard.
Micro button for bluetooth pairing function.
LED indicators for feedback of remaining power and bluetooth pairing status.
The Hall element of the silk screen AQ 2D is used to sense the magnetic field change when the charging case is turned on/off, and then notify the charging case MCU and earbuds to pair or disconnect with the connected device.
02/ Huawei FreeBuds 5 earbuds teardown
Enter the teardown part of the earbuds and open the earbud head along the parting line. A ring bracket is arranged inside the front cavity to fix the loudspeaker.
The internal structure of the rear cavity is sealed with a large amount of glue. The blue plastic is the structure of the bass enhancement conduit, which is equipped with an inverter tube and connected to the external pressure relief hole to enhance the low frequency effect.
Take out the speaker, the one on the right is the retaining ring.
The internal structure of the front cavity is equipped with a microphone and an in-ear detection sensor.
Take out the FPC inside the anterior cavity.
Optical in-ear detection sensor structure inside the front cavity.
The front diaphragm of the ultra-magnetic speaker.
Magnets on the back of the ultra-magnetic speaker.
After actual measurement, the size of the speaker is about 10.71mm.
The back-fed noise cancellation MEMS microphone of the laser engraving 234o is used to pick up sound from the inside of the ear canal.
Optical in-ear detection sensor, used to automatically pause audio playback when earbuds are taken off, and automatically resume playback when worn.
Take out the bass enhancement tube structure and microphone inside the rear cavity.
One side structure of the bass booster duct. The feed-forward noise cancellation microphone is fixed in the groove on the right side, and is protected by a fine dust-proof net. The microphone pickup hole on the other side is covered with a waterproof and breathable membrane.
The laser engraving 234o feed-forward noise cancellation MEMS microphone is used to pick up external environmental noise.
The bottom structure of the rear cavity is provided with a main board. The FPC is connected to the main board through the BTB connector.
Remove the inner cover of the headset stem. There is a battery unit inside the cavity, and the end FPC is connected to the microphone, which is sealed and fixed with a lot of glue.
There is an integrated lithium battery protection IC with silk screen printing “031 L21” on the FPC on the back of the battery.
Remove the battery and microphone. The main board FPC structure at the bottom of the cavity.
The earbud has a built-in steel shell button battery, and the QR code and “3836AAM725K07E5A” information are printed on the note.
Disassemble the headset stem and take out the motherboard.
The touch detection patch on the cavity wall is used for long press and slide control.
Main board and FPC front circuit.
There is a cover plate fixed on the back of the motherboard, on which the LDS laser antenna is printed. Remove the cover of the printed bluetooth antenna, and connect the inner side to the main board through contacts.
The circuit on the back of the motherboard.
Laser engraving 234o MEMS call microphone. A single earbud is equipped with three MEMS microphones of the same model, which are used for cooperative sound pickup of active noise cancellation and AI call noise cancellation functions.
BES BES2700YP bluetooth audio SoC has the characteristics of ultra-low power consumption and high integration. It adopts 12nm process technology, integrates dual-mode Bluetooth 5.3, and supports BT&BLE. The main processor has a built-in Arm Cortex-M55 CPU and Tensilica HiFi 4 DSP, which greatly improves the computing performance of the chip. The sensor hub subsystem has a built-in STAR-MC1 MCU and BES self-developed neural network processor BECO NPU, which realizes rich application processing capabilities while reducing power consumption.
The 24.0MHz crystal oscillator provides the clock for the bluetooth chip.
Screen printing 7 A36 acceleration sensor, used for tap control function.
Southchip SC7289 Linear Charging IC with system power path management and I2C interface for portable products where space is limited. SC7289 supports Bypass bypass mode, which can realize low-voltage direct charging at the earbuds. In shipping mode, SC7289 supports a low battery leakage current of 400nA, which prolongs the battery cycle life and enables users to obtain a better product experience.
SC7289 adopts WCSP-12 1.55mm X 1.95mm ultra-small package, which can be widely used in rechargeable battery packs with very small space constraints. SC7289 cooperates with SC8753 buck-boost chip inside the charging case, supports 10C direct charging, and has good thermal performance. The charging efficiency can reach up to 94%, which improves the overall battery life of the product.
SC7289 and SC8753 support load detection function, which can save the Hall switch for plug-in/out detection. Both SC8753 and SC7289 have built-in UART switches, eliminating the need for external load switches or MOS control. It also integrates charging case and earbuds communication functions.
Silkscreen AQ 2F IC.
Silkscreen K6 IC.
Connect to the BTB connector of the FPC of the front chamber assembly. As far as we know, the model number is: OK-114GF006-35, from OCN.
The BTB connector on the FPC of the internal component of the front cavity, model: OK-114GM006-35, from OCN.
All components of Huawei FreeBuds 5 true wireless noise cancellation earbuds.
Huawei FreeBuds 5 has changed the classic design of the previous two generations in terms of appearance. The charging case adopts a vertical “pebble” shape, and the open charging cockpit structure makes it easier to take and place earbuds. The earbuds adopts a very avant-garde unique design, a full-surface streamlined body, and a water drop-shaped headset stem, which is highly recognizable. At the same time, it has passed tens of thousands of ergonomic simulation tests to ensure the comfort of wearing.
In terms of internal main configuration, the charging case includes a motherboard, a battery, and an FPC connected to the earbud charging terminal, Hall elements, indicator lights, and function buttons. Built-in 3.87V high-voltage lithium battery with a capacity of 505mAh, and the battery comes from ATL. The motherboard uses Nations N32G4FR MCU single-chip microcomputer, Renesas DA9168 charging management chip to charge the built-in battery, and two Southchip SC8753 buck/boost converters, which are used to directly charge earbuds to improve charging efficiency.
The internal structure of the earbuds is quite unique. The earbud head is equipped with a ultra-magnetic drive unit, a feedback noise cancellation microphone and an optical in-ear detection sensor. The end of the headset stem is equipped with a steel shell button battery and a call microphone, and the main board unit and feed-forward noise cancellation microphone are fixed inside the middle end. The main control chip is BES BES2700YP bluetooth audio SoC, which supports dual-mode Bluetooth 5.3, and has the characteristics of ultra-low power consumption and high integration. The charging IC adopts the Southchip SC7289 chip, and cooperates with the SC8753 buck-boost chip in the charging case to realize direct charging with high magnification and ultra-high efficiency, bringing a revolutionary charging experience to TWS earbuds.