On October 19, the OPPO Smart Life Conference was successfully held, and officially released the acoustic flagship OPPO Enco X true wireless noise reduction earphones, the first flagship smart TV OPPO smart TV S1, OPPO smart TV R1 and LOL customized kits and other IoT ecological products. At the press conference, OPPO also demonstrated the seamless connection of true wireless earphoness with smart watches and smart TVs, giving users a new multi-terminal and cross-scene smart life experience.
As OPPO’s flagship acoustic earphones of the year, the OPPO Enco X true wireless noise-cancelling earphones was tuned by Daniel Emonts, chief acoustic expert of Dynaudio, with the exclusive DBEE 3.0 acoustic system, including superconducting magnetic planar diaphragm unit + three-layer composite large dynamic The driver’s coaxial dual-unit design is responsible for outputting high-frequency and mid-low frequencies, with distinct sound levels; at the same time, the earphones supports LHDC™ audio encoding format, with a transmission rate of 400kbps, and a sampling rate of 48kHz/24bit. Link optimization.
Compared with the previous OPPO Enco W31/W51, the appearance of the OPPO Enco X true wireless noise-cancelling earphones has changed a lot. The volume of the earphones has been greatly reduced, the overall quality is stronger, and the functionality is further enriched. OPPO Enco X supports multi-level noise reduction management, with four modes: strong noise reduction, weak noise reduction, noise reduction off and transparency. It also supports three-microphone call noise reduction and wireless charging, as well as characteristic touch and sliding interaction OPPO has also prepared the “Huanlu” APP for other Android phone users, which can realize the earphones touch customization function and firmware upgrade function in addition to the mobile phone pop-up window, providing users with a more convenient experience. Earlier, OPPO Enco X has also conducted an in-depth experience evaluation. If you are interested, you can click to view: OPPO Enco X: Not only the noise reduction true wireless, but also the ambition of OPPO smart ecology.
It is reported that OPPO Enco X is equipped with a customized version of the dual-core digital Bluetooth noise reduction chip, which supports Bluetooth 5.2. There are also new hardware configurations including speaker units and LDS antennas. It is bound to bring a comprehensive adjustment of the internal structure. Let’s take a look. Detailed dismantling of 52audio!
Earlier, 52audio had teardown the OPPO Enco W51, OPPO Enco W31, OPPO Enco Free, OPPO Enco Q1 and OPPO O-Free true wireless earphones.
01/ OPPO Enco X charging case teardown
After the previous unboxing, we have a detailed understanding of the design of the OPPO Enco X true wireless noise-cancelling earphones. Next, we will enter the disassembly process. The first to be disassembled is the charging case with a large change in appearance. Compared with the OPPO Enco W51, the volume is smaller, the battery capacity is increased, and it supports wireless charging. Let’s take a look at the solutions adopted by its wired charging power management system and wireless charging power management system!
Pry open the charging cockpit, you can see the internal structure of the charging case. The charging cockpit is fixed with multiple physical buckles and glue.
The internal structure of the metal shaft is displayed, and the sense of paragraph opening and closing of the box cover is realized by extruding a steel spring.
Remove the cover of the charging case.
The components inside the charging case are fixed on a plastic bracket.
Take out the internal support of the charging case, the battery and motherboard components are fixed on the support, and the wireless charging coil is attached to the inner wall of the box separately.
The inner side of the paired button uses a combination of a metal shell and a silicone button.
The protective cover inside the charging case indicator light prevents light leakage.
Internal structure display of charging case. The battery is fixed inside the bracket, and the outside is the motherboard.
The internal structure of the charging case is displayed on the other side. There is an FPC connected to the metal dome, Hall element, etc. that charge the earphones.
The connectors between FPC and motherboard are glued and reinforced.
NTC thermistor used to detect battery temperature.
The FPC is connected to the metal dome that charges the earphones.
On the inside of the charging cockpit, two special-shaped magnets are used to attach and fix the earphoness, and two magnets on the corners are used to attach the lid.
The Hall element that detects the lid opening.
The Hall element of AJOQ silk screen. The magnetic field changes when the charging box cover is opened and closed will be sensed by the Hall element, and then the charging box MCU and earphoness will be notified to pair or disconnect with the connected device.
The outside of the plastic bracket is displayed.
The inside of the plastic bracket is displayed, and there is cushion foam glue between the battery and the casing.
Internal circuit display of charging case.
The internal circuit of the charging case is displayed on the other side.
The circuit on the side of the motherboard is shown. The upper left corner is the solder joint of the wireless charging receiving coil connected to the motherboard, and the lower right corner is the solder joint of the battery wire. The solder joints are all reinforced with red glue.
Circuit display on the other side of the motherboard.
First of all, let’s look at the wired charging power management system, the Type-C interface for input power, and a hard plastic protective cover outside the interface, which has a certain degree of dust and water resistance.
The main board on the back of the Type-C interface uses Will SEMI ESD56241D18 18V TVS protection tube for input overvoltage protection.
Will SEMI ESD56241D18 details.
Near the Type-C interface, the overvoltage protection chip of LPS LP5306. LPS LP5306 is a high-precision over-voltage and over-current protection chip. The over-current value can be adjusted accurately. It can effectively protect the abnormal conditions such as over-voltage and over-current at the moment of power-on and after stable operation. It avoids damage to the back-end chip and has a built-in battery. The front end of the charger is overcharged protection to prevent the battery voltage from being too high to cause overcharge to cause battery swelling or other problems.
According to 52audio, there are already a large number of TWS earphones charging warehouses of well-known brands such as Xiaomi, OPPO, Huawei, Lenovo, realme, JLab, Skullcandy, AUKEY, Edifier, QCY, and Pimate have adopted the LPS solution.
Silk screen W26V IC.
Will SEMI WS4612 Load switch with current limit function, adjustable protection current, used for earphones charging overcurrent protection.
Will SEMI WS4612 details.
The boost IC of the silk screen ISOU boosts the built-in battery of the charging case to charge the earphones.
HDSC HC32L130F8UA microcontroller, used for charging case control.
TI BQ25619 charging management IC is responsible for charging the built-in battery in the charging case and boosting the current output from the charging case battery to charge the earphones.
The regulator IC of silk screen AIU.
About one-third of the battery surface is covered with graphite heat dissipation stickers.
Rechargeable lithium ion battery, model XA601, charging limit voltage 4.4V, rated capacity 535mAh/2.05Wh, nominal voltage 3.85V.
The supplier of the soft pack battery comes from ATL New Energy Technology Co., Ltd., model 741543.
A close-up of the battery protection board, the chip is sealed.
The wireless charging receiving coil is fixed on a layer of shielding sticker and pasted on the inside of the charging case.
A close-up of the wireless charging receiving coil. The transmitting coil of the wireless charger generates a certain current in the receiving coil based on a certain frequency of alternating current through the electromagnetic induction effect, thereby transferring electrical energy from the transmitting end to the receiving end, and then powering the battery in the TWS charging box.
Resonant capacitor and filter capacitor for wireless charging and receiving.
NuVolta NU1680 is a wireless power receiver with high integration, high efficiency, high compatibility, and high reliability. Compared with traditional wireless power receivers, it only requires fewer peripheral components. It is a low-cost, small area wireless power receiving solution.
Since no firmware is required for programming, NuVolta NU1680 will greatly simplify the design work and integrate solutions more easily and quickly. It integrates a synchronous rectifier, no bootstrap capacitor is needed, and it has the characteristics of high efficiency and low cost. It can provide wide-range voltage regulation from 3.5V to 9V, suitable for different applications. In addition, it can adjust the output voltage to track the battery voltage, further reducing the power consumption of the charging system.
NuVolta NU1680 can communicate with the launch system through ASK. Communication conforms to WPC V1.2.4. FOD parameters can be configured through the I2C interface or external resistors. NU1680 also supports I2C interface for communication. Provide external interrupt, battery voltage ADC value, output current, etc. NU1680 also supports standard protection functions such as overcurrent protection, short circuit protection, overvoltage protection and thermal shutdown. These protective measures further improve the reliability of the system solution.
NuVolta NU1680 detailed information.
The IC of silk screen TT.
Close-up of two LED indicators.
The jog button on the side of the fuselage is welded to the motherboard.
02/ OPPO Enco X earphones teardown
Next, let’s disassemble the OPPO Enco X earphones. The appearance is more changed than the previous OPPO Enco W31/W51. The volume of the earphones is greatly reduced, the handle of the earphones is shortened, and the shell curve of the body at the ear is more suitable for human ears and enhanced. Improved wearing comfort.
The outer shell of the OPPO Enco X earphones handle continues the previous OPPO Enco W51’s “symphony diaphragm” design, which emits rainbow-like colors at different angles.
The feedforward microphone on the top of the earphones handle is mainly used to pick up ambient sound and assist in active noise reduction and call noise reduction.
The bar-shaped charging contacts at the bottom of the earphones handle distinguish the positive and negative poles by the length of the metal contacts. The product model “OPPO ETI51” is on the inside of the earphones handle.
The pickup hole of the call microphone.
The strip-shaped pressure relief hole/tuning hole adopts metal dust-proof net to prevent foreign matter from entering, which can play a tuning role and a certain decorative role.
Pressure relief hole/tuning hole near the sound hole.
The sound hole adopts a metal dust-proof net, and there is a layer of higher-density dust-proof net for double protection. At the same time, the metal dust-proof net on the outside also increases the design and texture of the product, and the overall style of the fuselage is more unified.
Disassemble the outermost decorative cover of the earphones by heating.
There is a sealed cover inside. The cover has a dust-proof net for the microphone, an LDS antenna for the earphones, and an FPC for detecting tap/press/slide operations.
Carefully provoke the FPC that detects touch operations.
The sealing cover is fixed with a large amount of glue, which plays a certain role in dustproof and waterproof. There is a metal dome on the main board to connect the LDS antenna.
Close-up of the outside of the sealing cover. Pay attention to the transparent structure at the bottom, a sound guide design is made for the call microphone, and it also has a certain dust and waterproof effect.
Close-up of the inside of the sealing cover.
The internal structure of the earphones handle is displayed.
The strip-shaped main board is connected to the main board in the sound cavity through a flexible flat cable.
Remove the charging contacts of the earphones.
Remove the shell of the earphones.
Display inside the shell.
Display inside the earphones handle housing.
The dust-proof net inside the microphone hole of the call.
The internal circuit of the earphones is displayed.
The internal circuit of the earphones is shown from another angle. The magnet used to absorb the earphones is fixed on the transparent plastic frame with glue. The coaxial line in the picture is used as the signal transmission of the bluetooth antenna, extending from the main board to the microphone sub-board and then contacting the bluetooth antenna.
The circuit on the other side of the strip FPC is shown, and there are two microphones on the earphones motherboard.
Disconnect the FPC on the motherboard. There are two PCBAs in the sound cavity, one is pasted on the battery, and the other is standing between the sound cavity and the battery. The top two solder joints in the picture are the positive and negative poles of the moving coil unit.
The two solder joints at the bottom of the picture are the positive and negative electrodes of the battery, which are reinforced with red glue.
Before removing the button battery and the motherboard, you need to solder off the unit cable.
The arc magnet that absorbs the charging cockpit is pasted on the frame that fixes the battery.
The chip motherboard of the earphones is attached to the inner wall of the earphones shell. After removing the battery, you need to clean the white silicone that fixes the motherboard before you can completely take out the motherboard and its components. Because the earphones is small in size, there are many cables and they are all glued and reinforced. Be careful.
The battery is fixed on a transparent bracket.
Take out the battery and related circuits.
The main circuit inside the earphones is compared with the size of a coin.
Connect two PCBAs on the same axis and fix them on one side of the battery with adhesive tape.
Remove this coaxial cable.
The circuit on the side of the strip-shaped motherboard is shown with a feed-forward microphone and a call microphone.
The circuit display on the other side of the strip motherboard.
Connect the metal dome of the LDS antenna.
The pickup hole of the call microphone.
Laser carving G292 0B79 MEMS silicon microphone.
GOODiX GH611 in-ear detection and touch 2 in 1 solution.
GOODiX GH61x series chips, using human capacitance detection patented technology, can assist true wireless earphoness to achieve automatic sleep, automatic wake-up, master-slave switching, automatic music start and stop and other functions, improve user experience, and support touch control, sliding volume adjustment and other rich Human-computer interaction function.
The GH61x series adopts dual-channel in-ear detection and the characteristic that the capacitance detection scheme only responds to electrodes, making it have a lower false recognition rate than traditional optical detection schemes. The chip integrates PMU and MCU, the algorithm runs independently on the chip, and reports events directly to the main controller, without the main control for data processing.
According to 52audio, TWS earphoness from brands such as Baidu, OnePlus, vivo, OPPO, etc. have also adopted GOODiX’s in-ear detection and touch control 2-in-1 solution.
There is a PCBA on the battery, and on the left is the connector of the flat diaphragm unit, the feed-back microphone and the FPC of the ear detection antenna.
The solder joints of the positive and negative electrodes of the battery.
Solder the solder joints of the battery.
PCBA is shown on the other side, with insulating tape between it and the battery.
The button battery supplier comes from Changzhou MBT Electronic Technology Co., Ltd., model MBT MC1054C, rated voltage 3.85V, rated capacity 46mAh.
For the first time, the MBT miniature button battery adopts the negative design of the shell, the positive and negative leads are output from the top, and the degaussing circuit is added to the top of the cell, which achieves zero electromagnetic interference and greatly saves system space.
Different from the traditional button riveting structure and plastic sealing method, after three years of research and development, the MBT micro button battery has pioneered glass-sealed lithium ion battery technology and glass-sealed explosion-proof valve technology. It uses corrosion-resistant high-strength glass-ceramics and special high-pressure resistance. Stainless steel, precision laser welding on the cover, positive and negative poles on the same side.
It is reported that MBT’s first permanent sealing solution has passed the patent review of many brands and can provide higher capacity under the same voltage size.
Silk screen TI06AC068 IC.
The IC of the silk screen ADCN is sealed with glue.
The bluetooth master chip and its related circuits are on a single PCBA.
The other side of the PCBA is shown, using a large amount of white glue to fix it on the inside of the shell. The upper right corner is the coaxial socket that connects to the strip-shaped motherboard.
The main control chip of OPPO Enco X true wireless noise reduction earphones is Bestechnic BES2500Y. It is reported that this is Bestechnic’s new generation of smart TWS bluetooth chip, which supports bluetooth 5.2 and adaptive active noise reduction.
52audio learned that at present, a large number of true wireless earphoness from brands such as Huawei, Samsung, Xiaomi, OPPO, JBL, 1MORE, Honor, Baidu, and OnePlus have adopted Bestechnic solutions.
Continue to disassemble the sound cavity and look at the coaxial dual unit design of OPPO Enco X.
Take out the transparent bracket holding the button battery.
The speaker unit is sealed with blue glue, and the FPC used for in-ear detection is also glued to the shell.
First take out the inner moving coil unit.
Another plane diaphragm unit.
The larger moving coil unit is welded to the circular PCBA by FPC, and the flat diaphragm unit is connected to the FPC for in-ear detection by FPC.
In-ear detection of the FPC position, covering a large area.
The in-ear detection FPC basically covers the inside of the housing where the earphones enters the ear. A feed-back microphone is fixed on the upper side of the sound hole.
Remove the feed-back microphone.
Laser carving G282 0A18 MEMS silicon microphone.
The moving coil unit size is about 11mm.
The size of the flat diaphragm unit is about 6mm.
Flat diaphragm unit display.
The sound hole of the flat diaphragm unit.
There is a metal protective cover outside the moving coil unit.
T iron of the moving coil unit.
All components inside the OPPO Enco X earphones.
OPPO Enco X true wireless noise reduction earphones have undergone a comprehensive upgrade from the packaging box to the product’s software and hardware, highlighting the positioning of the flagship product. The earphones is still designed as a handle-type earphones, but the earphones handle is shorter and the size of the earphones cavity is smaller, which enhances the wearing comfort. The shell continues the previous “Symphony Coating” design on the OPPO Enco W51, and the metal dust screen The design is also more beautiful, which further enhances the appearance; the charging case adopts a new cobblestone-like shape, and the silver waistline pays tribute to OPPO’s classic MP3 design. OPPO Enco X has a better quality on the real machine, which is the level of flagship TWS earphones.
In terms of internal circuits, the internal components of the OPPO Enco X charging case are fixed on a plastic bracket, the battery is inside the bracket, and the battery is outside the motherboard, making full use of the vertical space; Type-C interface input power, by Will SEMI TVS protection tube and LPS LP5306 Together to provide input overvoltage protection, TI BQ25619 is responsible for battery charging and discharging, Will SEMI WS4612 is used for overcurrent protection of earphones charging. The soft pack battery comes from ATL with a capacity of 535mAh. The charging case wireless charging receiving solution comes from NuVolta NU1680, which supports the Qi standard, has high integration and simplified peripheral components; the HDC MCU is responsible for charging case control.
In the earphones part, OPPO Enco X has a very simple appearance, but the internal structure design is more complicated. There are three PCBAs in the earphones. The three PCBAs are connected together by a flexible cable. The bluetooth main control chip related circuit is on a single PCBA, which is connected to the metal dome of the strip main board through a coaxial cable, and then contacts the earphones cover The LDS antenna on the board transmits signals. The LDS antenna is designed along the earphones handle to increase the angle and area of signal reception; there is an FPC in the earphones that connects the flat diaphragm unit, the feed-back microphone and the in-ear detection FPC, and the dynamic driver is welded to the FPC The third PCBA, MBT micro button battery is also welded on the third PCBA, with a capacity of 46mAh. The button battery is a patented design, and the positive and negative leads are output from the top, saving the internal space of the earphones.
The main control chip of OPPO Enco X is Bestechnic BES2500Y. It is reported that this is a dual-core digital bluetooth noise reduction chip that supports bluetooth 5.2, which further improves the stability and delay performance of the connection; OPPO Enco X uses the new chip mainly to balance multiple The demand for a variety of noise reduction modes, the sound quality performance of the coaxial dual unit, and power consumption control. The two-in-one solution of in-ear detection and touch control is the familiar GOODiX GH611. The internal space of the earphones is very compact, and the design and production are not small.