TOZO is an American best-selling audio brand. Its products include true wireless earphones, smart watches, power banks, chargers, mobile phone protective cases, etc., which have very good sales in overseas markets. The one that will teardown this time is TOZO NC7, one of its true wireless active noise cancelling earphones.
The TOZO NC7 charging case is compact and lightweight, and the earphones are bean-shaped in-ear ergonomic design with multiple elastic eartips for a comfortable fit. Functionally, it supports ANC/transparency mode and dual-mic call noise cancelling. Equipped with optical sensor to provide accurate wearing detection function. In terms of battery life, the single battery life can reach more than 8 hours, and the overall battery life with the charging case is 32 hours. It supports wireless charging and is compatible with most wireless chargers.
52audio has previously teardown TOZO brand products including: TOZO NC2 true wireless noise cancelling earbuds, TOZO T12 true wireless bluetooth earphones, TOZO T9 true wireless earbuds. Let’s take a look at the detailed teardown report of this product.
|1. TOZO NC7 charging case teardown
After reading the appearance design of the product, enter the teardown section below. Let’s take a look at the internal circuit and configuration information.
Remove the snap-on earphone charging pod.
The bottom structure of the cockpit is equipped with four cylindrical magnets for attaching headphones and charging case.
The internal structure of the charging case cavity, the uppermost motherboard is fixed by screws.
Below the motherboard is a battery unit, and a wireless charging receiving coil is attached below the battery.
Take out the main components in the charging case and the internal structure of the cavity.
One side of the circuit inside the charging case.
On the other side of the circuit inside the charging case, you can see the professional-grade waterproof Type-C socket on the motherboard, which shows how much TOZO attaches great importance to waterproofing this time.
The wireless charging receiving coil is set on the magnetic shielding sticker.
A thermally conductive silicone pad is arranged on the back of the shielding sticker where the battery is connected.
The internal soft pack battery model of the charging case: 112222PN3, rated voltage: 3.8V, rated capacity: 500mAh, 1.9Wh, from VDL.
The battery is equipped with a circuit protection board and a lithium battery protection IC, which is reinforced with glue.
The front circuit of the charging case motherboard.
The circuit on the back of the charging case motherboard.
Type-C charging interface female seat, the interface is provided with a sealing pad, which is a professional waterproof Type-C interface.
The Hall element of the silkscreen 4002 0nAG is used to sense the magnetic field changes when the charging case lid is opened and closed, and then notify the charging case MCU to control the earphone to pair or disconnect from the connected device.
A power inductor that works with the boost chip to charge the earphones.
The pogo pin connector on the motherboard for charging the earphone.
Four indicator lights, wrapped in black foam to prevent light leakage.
Screen printing 001 microcontroller.
LY ICP1106 power management chip integrates switching charging, Boost synchronous boosting, power path management, binaural independent plug detection, two-way communication, OVP, OCP protection and other functions. It has the characteristics of powerful performance, high integration, and simple peripheral circuits.
The charging voltage, charging current and output voltage of ICP1106 can be flexibly configured through I2C, which can easily realize TWS fast charging and efficient charging. At the same time, it supports two communication modes of power line carrier two-way communication and UART two-way communication, which can reliably meet the information interaction requirements of the charging compartment and the earphone, and realize the intelligent control of the earphone and the charging compartment.
ICP1106 also supports transport mode, the standby power consumption can be as low as 1uA, and supports 0V, 2.4V, battery voltage and other voltage output standby modes.
52audio learned from previous dismantling that Belkin SOUNDFORM Freedom true wireless headphones and omthing AirFree2 true wireless noise cancelling earbuds also use this power management chip product.
The NuVolta NU1680 is a small size, highly integrated wireless power receiver that integrates a synchronous rectifier without bootstrap capacitors for high efficiency and low cost. It can provide a wide range of voltage regulation from 3.5V to 9V, which is suitable for different applications. And can adjust the output voltage to track the battery voltage and reduce the power consumption of the charging system.
NuVolta NU1680 can communicate with the transmitting system through ASK, and the communication conforms to WPC V1.2.4; FOD parameters can be configured through I2C interface or external resistance. NU1680 also supports I2C interface for communication. Provides external interrupts, battery voltage ADC value, output current, etc. The NU1680 also supports standard protection functions such as overcurrent protection, short circuit protection, overvoltage protection and thermal shutdown.
|2. TOZO NC7 earbuds teardown
Enter the teardown part of the earphone and pry open the earphone cavity along the parting line.
The internal structure of the front cavity, the speaker and the power input board are all fixed by a large amount of glue, which plays a good sealing and waterproofing effect.
The internal structure of the rear cavity is provided with a plastic bracket to fix the internal components.
Take out the main components in the rear cavity, and connect the cables of the microphone, the antenna and the touch detection patch on the motherboard.
The internal structure of the rear cavity has a bluetooth antenna and a touch detection patch attached to the bottom and a microphone on the side.
Laser engraving MD03 H118’s MEMS microphone for voice pickup.
The internal battery of the earphone and the motherboard unit teardown.
The inside of the earphone uses a soft-pack button battery, equipped with a circuit protection board, and the outer layer is wrapped with Mara tape for insulation.
On the back of the battery, there is a QR code on the silk screen, and the battery information can be traced back.
Silkscreen G60 QSOq integrated lithium battery protection IC.
The soft-pack button battery inside the earphone is 1350PN2, the voltage is 3.7V, and the capacity is 0.266Wh.
The circuit on the side of the headphone motherboard.
The circuit on the other side of the headphone motherboard.
Touch chip, silk screen YSC612.
BTB connector for connecting the cable of components inside the front chamber.
Connect the pogo pin connector of the bluetooth antenna.
ZIF connector for connecting feedforward microphones.
AIROHA AB1562A bluetooth audio SoC, which has ultra-low power consumption, stable bluetooth connection and Hybrid active noise cancelling function, integrates all functions into one. The chip has built-in Hybrid ANC, and provides a new generation of three-microphone noise cancelling technology. With the Airohanoise cancelling algorithm, it can significantly reduce wind noise and improve call quality.
AIROHA AB1562A has built-in Tensilica HiFi mini DSP, 2MB/4MB flash memory, integrated lithium battery charging controller and power management circuit. In terms of bluetooth specifications, it supports Bluetooth 5.2 dual-mode, and supports bluetooth low energy mode, supports A2DP, HFP, AVRCP, SPP and other functions.
According to 52audio, the true wireless earphones on the market including Sony, Zepp Health Corporation, 1MORE, realme, FIIL, Edifier, Plantronics, earsopen and other brands have widely adopted the AIROHA solution.
The crystal oscillator that provides the clock for the bluetooth chip.
The MEMS feed-forward noise cancelling microphone of the Laser Engraving 3A2 H18 is used for the noise cancelling function to pick up external environmental noise.
Take out the internal components of the front chamber and the internal structure of the housing.
Front cavity internal component circuit.
The front of the dynamic driver.
On the back of the dynamic driver, there is a tuning hole in the middle, which is protected by a dust-proof net.
After actual measurement, the speaker size is about 7mm.
The power input small board has an optical sensor between the two metal copper columns, which is used for the in-ear detection function, and realizes the function of automatic pause when picking and automatic resume playback when wearing.
The internal components of the front cavity are all connected to an FPC cable, and the end of the cable is connected to the motherboard through a BTB connector.
Laser carving MC38 H121’s MEMS feedback noise cancelling microphone is used to pick up the noise inside the ear canal.
TOZO NC7 true wireless noise cancelling earbuds all components.
The TOZO NC7 true wireless noise cancelling earbuds continues the TOZO family-style design style in appearance, and the overall design is more layered and highly recognizable. It adopts a horizontal square design, a matte texture, and is compact and lightweight. The earphone is a bean-shaped in-ear design, the opening of the lattice microphone is very unique, and there are 6 types of silicone eartips in two forms, round and flat, which effectively improves the personalized wearing and use needs.
In terms of internal circuits, the charging case has a built-in 500mAh battery, is equipped with a circuit protection board and a protection IC, and supports both wired and wireless input power. The cable adopts the LY ICP1106 power management chip, which integrates switching charging, Boost synchronous boosting, power path management, binaural independent plug detection, two-way communication, OVP, OCP protection and other functions. The wireless adopts Voda NU1680 wireless power receiver, which has the characteristics of high efficiency and low cost.
The headphone part uses a 7mm dynamic driver, a 0.266Wh soft pack button battery, an optical in-ear detection sensor and 3 MEMS microphone units. The main control chip is Airoha AB1562A bluetooth audio SoC, which has ultra-low power consumption, stable bluetooth connection and Hybrid active noise cancelling function, supports three-microphone noise cancelling technology, and cooperates with Airoha noise cancelling algorithm to improve call quality.
According to 52audio, since the establishment of TOZO in 2015, TOZO products can often be seen in the headphone rankings on Amazon, which belong to the best-selling audio brand in the United States. Its products include true wireless earphones, smart watches, power banks, chargers, mobile phone protective cases, etc., which have very good sales in overseas markets.
This time, TOZO NC7 performed well at the CES exhibition in the United States in 2022 with its overall small size and long battery life. The battery capacity of the charging case is 500mAh, and the battery capacity of the earphone is 70mAh, which has won the favor of consumers.