Technics is Panasonic’s high-end HiFi brand, which was born in 1965. Its products include high-end record players, power amplifier equipment, CD players, audio equipment, headphones, etc. Recently, the Technics series has released three iterative new products. We have recently shared Technics EAH-AZ40M2 Review, Technics EAH-AZ80 Review, and Technics EAH-AZ40M2 Teardown. This time let’s take a look at the internal structure and configuration of Technics EAH-AZ80.
01/ Technics EAH-AZ80 Charging Case Teardown
Pry open the charging case and take out the internal charging bin structure.
The front structure of the charging bin has the battery fixed in the middle and the motherboard at the top.
The structure on the back of the charging bin.
The bottom structure of the charging bin fixes the wireless charging receiving coil through a transparent bracket.
Remove the screws and remove the clear bracket.
The motherboard unit structure at the bottom of the charging bin is fixed with screws.
Remove the screws and remove the motherboard unit.
Charging case motherboard side circuit.
Charging case motherboard side circuit.
Connect the battery’s wire socket.
The charging case is a Pogo Pin connector for earbuds charging and communication.
TI BQ25616J is a self-contained single-cell 3.0A step-down battery charger with power path and 1.2A boost operation. Highly integrated 3A switch-mode battery charge management and system power path management for single-cell Li-ion and Li-polymer batteries. The solution is highly integrated between the system and battery input reverse blocking FET (rfet, Q1), high-side switching FET (HSFET, Q2), low-side switching FET (lfet, Q3) and battery FET (BATFET, Q4) . The low-impedance power path optimizes switch-mode operating efficiency, reducing battery charging time and extending battery operation time during the discharge phase.
Silk screen 1SOU 198 boost IC.
Power management chip peripheral power inductor.
The lamp bead that provides light source for the indicator light inside the charging bin.
LED lamp beads that provide light source for the indicator light at the cover opening.
Silk screen 1365 NNNJ MCU microcontroller for charging case control.
Two silk screen D9 ICs.
Silk screen ARBP 122 IC.
TI BQ51003 wireless receiver power supply, compliant with WPC V1.2 standard, optimized for 2.5W applications, with an overall peak AC/DC conversion efficiency of 93%. Integrates a fully synchronous rectifier, low-dropout voltage regulator, digital control, and precise voltage and current loops for earbuds wireless charging reception.
The charging case has a built-in rechargeable lithium-ion battery pack, model number: 102427, charging limit voltage: 4.2V, nominal voltage: 3.7V, rated capacity: 700mAh 2.59Wh, manufacturer: Chongqing VDL Electronics Co.,Ltd.
The socket where the battery wires connect to the motherboard.
Tear off the external insulation protection of the battery, and the silk screen information on the battery core is consistent with the external label.
The battery is equipped with two PCB protection boards. PCB-A is connected to the positive and negative nickel plates of the battery, and a BOURNS battery circuit breaker is installed on it for battery overheating and overcurrent protection.
The wire connecting PCB-B to the motherboard is equipped with a lithium battery protection IC and MOS tube.
Silk screen 6C 224 lithium battery protection IC is responsible for battery overcharge, overdischarge, overcurrent and other protection functions.
Silk screen 2007 NI MOS tube.
02/ Technics EAH-AZ80 Earbuds Teardown
Open the earbud cavity; there is a power input board inside the front cavity, and the bass duct structure of the speaker is on the right side.
The internal structure of the back cavity has the battery fixed in the middle and the main board at the bottom.
Feedback noise cancellation microphone structure.
The internal structure after removing the sound chamber cover.
The speaker unit structure.
Take out the components on the front cavity.
The power is input to the circuit on one side of the motherboard, and the speaker wires are soldered to the motherboard.
The power input is to the circuit on the other side of the motherboard.
Vesper VA1210 acceleration sensor is a high-performance, low-noise differential analog piezoelectric MEMS voice accelerometer. Featuring Vesper’s adaptive zero-power sensing, dramatically extending battery life in always-on systems. Adaptive ZeroPower Sensing continuously monitors background acceleration levels to activate the system when preconfigured acceleration thresholds, such as the user’s voice, are detected. The entire signal chain of the ZeroPower sensing system is in sleep mode while sensing speech.
Silk screen XDK IC.
Feedback noise cancellation microphone circuit. On the right is the feedback noise cancellation microphone of the Lasdiao 173A03, which is used to pick up noise from inside the ear canal.
Optical in-ear detection sensor FPC circuit.
Infrared distance sensor is used for in-ear detection function to automatically pause music playback when taking off the earbuds and automatically resume playback when wearing them.
The front of speaker diaphragm.
On the back of the speaker, there is a tuning hole in the middle, which is protected by a wire mesh.
After actual measurement, the speaker size is about 10mm.
Remove the middle frame of the rear cavity and the battery is fixed in the transparent frame.
The small plate fixed on the side of the frame is welded to the battery wires.
Remove the transparent frame and take out the battery.
The earbuds have a built-in soft-packed button battery, which is protected by high-temperature insulating tape. Tear off the insulation protection, silk screen information on the battery cell – model: 1454; energy: 0.32Wh; voltage: 3.7V; from VDL.
Main board structure inside the rear cavity cover.
The circuit on one side of the motherboard.
The circuitry on the other side of the motherboard.
AIROHA AB1565M bluetooth audio SoC. The AB1565x series is Airoha’s advanced bluetooth audio solution, supporting Bluetooth 5.3 and capable of supporting LE audio. The latest multi-point for TWS can connect laptops and mobile phones at the same time and switch easily. Providing ultra-low power consumption and ultra-low latency performance, the average power consumption can reach ~4.x mA, which is the leading power consumption level in the current bluetooth audio market. AB1565x also has stable bluetooth connection, clear sound quality and Hybrid ANC function, providing rich and powerful performance for bluetooth headsets.
The peripheral crystal oscillator of the bluetooth chip is used to provide the clock.
Silk screen LGV IC.
Silk screen C 2CQ IC.
The feedforward noise cancellation microphone of the Lasdiao 6D5 W28 is used for the noise cancellation function to pick up external environmental noise.
Silk screen C3A1A 21110T DSP chip, there are two in total.
The MEMS microphone of Lasdiao 6D5 W28 is used for voice call function to pick up vocals.
Small board circuit to connect the battery.
Silk screen 761PKIU2 lithium battery protection IC.
Sensor circuit for detecting battery temperature.
Touch sensor for touch control functions.
All components of Technics EAH-AZ80 true wireless noise cancellation earphones.
Technics EAH-AZ80 has further upgraded its texture compared to previous generations. The charging case adopts a metal-like coating and is designed with a brushed metal texture to enhance the detail. The bean-shaped in-ear earbuds use the combination of two processes, which not only improves the quality of the product, but also ensures comfort. However, due to the addition of many configurations and the built-in larger-capacity battery, its size and weight have also increased significantly.
The charging case has a built-in VDL 700mAh large-capacity battery and supports both wired and wireless charging methods. Wired charging uses TI BQ25616J battery charger, which integrates 3A switch-mode battery charging management and system power path management. The low-impedance power path optimizes switch-mode operating efficiency, reduces battery charging time, and extends battery operating time during the discharge phase. Wireless charging uses TI BQ51003 wireless receiver power supply, which complies with WPC V1.2 standard and is optimized for 2.5W applications. The overall peak AC/DC conversion efficiency is 93%.
The earbud is equipped with a 10mm dynamic driver and three built-in MEMS microphones + Vesper VA1210 acceleration sensor for voice calls and noise cancellation functions. An infrared distance sensor is used to achieve in-ear detection, and a capacitive touch sensor is used to achieve touch control. Use VDL 0.32Wh soft pack button battery. The main control chip is AIROHA AB1565M bluetooth audio SoC, which supports Bluetooth 5.3, multi-point connection, and Hybrid ANC. It is also equipped with two DSP chips to improve sound quality performance.
Translated from 52audio