Recently, SHOKZ launched a new open-ear headphones with air conduction design – SHOKZ OpenFit. Similar to the split design of TWS earbuds, ear-hook structure, double-layer zero-degree silicone material, non-in-ear wear, providing an all-round comfortable wearing experience. It is also equipped with a charging case for storing and charging the headphones, improving portability and battery life.
SHOKZ OpenFit is equipped with a custom high-amplitude, high-sensitivity drive unit, bringing abundant bass and strong and stable high-frequency. With the Shokz OpenBass low-frequency enhancement algorithm, DRC dynamically adjusts the sound quality, bringing a natural hearing sense with sufficient quantity sense. Built-in dual microphones, support AI smart call noise cancellation function, protect human voice, effectively eliminate environmental noise and call echo, and provide clear voice call effect. It is also equipped with DirectPitch directional sound field technology, accurate and efficient sound transmission, and privacy protection.
The headphone has a single battery life of up to 7 hours, and a comprehensive battery life of up to 28 hours. Also support fast charging function – charging for 5 minutes, music playback for 1 hour. Let’s take a look at the detailed teardown report of this product.
01/ SHOKZ OpenFit charging case teardown
Disassemble the charging case cover and take out the headphone cockpit structure. There are magnets, metal thimbles and wires for charging the headphones at the bottom of the cockpit.
Connector for charging the headphones. On one side is the plug where the wire connects to the motherboard, and on the other side is the Pogo Pin connector.
The internal structure of the charging case. The main board is fixed by screws, the battery is fixed in the positioning slot by glue, and the battery wires are connected to the main board by sockets.
The circuit on the side of the motherboard of the charging case.
The circuit on the other side of the charging case motherboard.
GigaDevice GD32L233CCT6 microcontroller. GD32L233xx series is a new 32-bit general-purpose microcontroller based on ARM Cortex-M23 core, with a maximum frequency of 64MHz. It integrates 64KB to 256KB of embedded eFlash and 16KB to 32KB of SRAM, as well as various enhanced I/O and peripheral resources connected to two APB buses.
The Cortex-M23 processor is an energy-efficient processor with an extremely low gate count designed for use in microcontrollers and deeply embedded applications requiring an area-optimized processor. The processor provides energy-efficient processing capabilities through an instruction set and extensively optimized design, including high-end processing hardware including a single-cycle multiplier and a 17-cycle divider.
The crystal oscillator that provides the clock for the microcontroller.
Screen printing 6UC3 AAE8 IC.
Two sets of LED indicators with different colors are used to feedback the status of headphone charging and bluetooth pairing.
Connect the lead wire socket of the battery.
TI’s BQ25619 power management chip integrates charging, boost converter and voltage protection into a single device for charging batteries and headphones.
The BQ25619’s best-in-class low quiescent current reduces battery leakage to 6uA in ship mode, saving battery power and doubling device shelf life. The BQ25619 is available in a 4×4 QFN package.
The power inductor, together with the power management chip, is responsible for the charge and discharge management of the battery.
Screen printing MK71 regulator IC.
Connect the socket of the Pogo Pin connector.
The Hall element of the silk screen AJ 2S corresponds to the magnet at the bottom of the cockpit, which is used to sense the magnetic field change when the charging case is turned on/off, and then notify the charging case MCU and headphones to pair or disconnect with the connected device.
The charging case built-in lithium battery model: EVE 472640GH, nominal voltage: 3.85V, rated capacity: 600mAh 2.31Wh, from EVE.
The battery protection board circuit is equipped with an integrated lithium battery protection IC and a thermistor.
Screen printing 192XCAA BC’s integrated lithium battery protection IC is responsible for battery overcharge, overdischarge, overcurrent and other protection functions.
02/ SHOKZ OpenFit headphones teardown
Enter the headphone teardown section. Remove the back cover of the headphone to see the internal structure of the cavity.
The inside of the cover is provided with a bracket printed LDS laser antenna and touch detection electrodes.
The main board unit structure inside the cavity.
Take out the main board, and the lower speaker unit structure is provided with a transparent plastic part to seal the sound cavity.
The circuit on one side of the headphone motherboard.
The circuit on the other side of the headphone motherboard.
Connect the BTB connector of the battery FPC.
The 24.000MHz crystal oscillator provides the clock for the bluetooth chip.
Connect the Pogo pin connector of the touch detection electrode.
GOODi GH611 capacitive in-ear detection and touch 2-in-1 chip is used for the touch control function of the headphones. GOODi GH61x series chips adopt the patented technology of human body capacitance detection, which can assist true wireless earphones to realize automatic sleep, automatic wake-up, master-slave switching, automatic start and stop of music and other functions. Improve user experience and support rich interactive functions such as touch and sliding volume adjustment.
The GH61x series adopts dual-channel in-ear detection and the capacitive detection scheme only responds to electrodes, which makes it have a lower false recognition rate than traditional optical detection schemes. The chip integrates PMU and MCU, and the algorithm runs independently on the chip, directly reporting events to the main control, without the need for the main control to do data processing.
Silkscreen 22A7T2 IC.
BES BES2500YP ultra low power bluetooth audio SoC. Supports dual-mode Bluetooth 5.2, and integrates high-fidelity audio DAC and ADC. By integrating the high-performance dual-core STAR-MC1 MCU subsystem and the ultra-low power Sensor Hub subsystem, the power consumption is greatly reduced, and it also has powerful application processing capabilities. And optimize the TWS application through BES IBRT technology, improve the RF performance in the TWS system. It can also support functions such as adaptive ANC noise cancellation.
The MEMS microphone of Leidiao SG01 is used to pick up the sound of the noise cancellation function of the call.
Pogo pin connector to connect the bluetooth antenna.
Silk screen 13 IC.
Disconnect the wires and remove the speaker.
The internal structure of the cavity is equipped with metal connectors, microphones and battery wires for the FPC to charge the headphones.
The front diaphragm of the headphone custom-made super large dynamic drive unit is made of lightweight polymer material to bring abundant bass experience. Double-layer super smooth carbon fiber provides strong and stable high-frequency output.
After actual measurement, the length of the drive unit is 18mm, the width is about 12.23mm, and the thickness is about 4.76mm.
Extract the FPC, the circuit on the FPC.
Silkscreen SG01 MEMS microphone for voice pickup.
Three metal connectors for headphone charging and communication.
The BTB connector that connects the FPC to the motherboard.
Remove the earhook end structure.
There is a soft-packed lithium battery in the cavity at the end of the earhook, and the battery is wrapped and protected with high-temperature insulating tape.
The battery wire is connected to the main board, and there is a silk screen 2P integrated lithium battery protection IC on the main board.
The built-in lithium battery model of the headphone: AEC 08170, capacity: 0.22Wh, voltage: 3.85V, from AEC.
All components of SHOKZ OpenFit no-in-ear bluetooth sprots headphones.
As SHOKZ’s first non-bone conduction headphones, SHOKZ OpenFit still brings a comfortable and high-quality open wireless listening experience based on its innovative exploration and technology accumulation in the field of acoustics. In appearance, the charging case adopts a rounded square design with a delicate matte texture. The headphones adopts a separate earhook design, which is more free and flexible to use. It is equipped with flexible titanium wire memory earhooks and double-layer zero-degree skin-friendly silicone material to provide a personalized and comfortable wearing experience.
In terms of internal configuration, the charging case has a built-in EVE 600mAh lithium-ion battery pack. The main board is powered by the Type-C interface, and adopts TI BQ25619 power management chip, which integrates charging, boost converter and voltage protection functions, and is used to charge the battery and headphones. A new 32-bit microcontroller with GigaDevice GD32L233CCT6 Arm Cortex-M23 core is used for charging case control.
The internal design of the headphone is exquisite, and the built-in AEC 0.22Wh lithium battery is located at the end of the ear hook, which balances the weight of the headphone and improves the wearing comfort and stability of the headphones. The headphone is equipped with a custom super large dynamic drive unit and two MEMS microphones to pick up sound. The motherboard adopts BES BES2500YP ultra-low power consumption bluetooth audio SoC, GOODiX GH611 capacitive in-ear detection and touch 2-in-1 chip, etc.
Check the Shokz OpenFit price:
- Check latest price on AliExpress