Not long ago, the well-known intelligent voice and artificial intelligence research enterprise KU Xunfei released its first TWS true wireless headset iFLYBUDS, this TWS headset focuses on real-time transcription of the call, intelligent dialing, translation and textual control, etc., aimed at allowing business people to liberate their hands in multiple scenarios such as commuting, meetings, self-driving, etc., and to efficiently record and comfortably communicate, previously I love audio network has conducted a The audio network has already carried out a comprehensive experience review.
Configuration, KDDI iFLYBUDS built-in 14mm speaker unit, dual microphone pickup, support for CVC call noise reduction, headset support for in-ear detection, tap control and wake up voice assistant function, music lasts for 4 hours, call + recording + transcription lasts for 2 hours, the charging box can be charged for the headset four times.
Intelligent voice functions such as call recording and text transcription apply KU Xunfei AI technology algorithms, and iFLYBUDS uses a flagship chip to ensure the stability of use. How about its internal structure and materials, together with the detailed disassembly of I love audio network!
First, the Xunfei intelligent headset iFLYBUDS unboxing
The box is a square design of the sky and earth cover, the packaging is relatively simple, the headset inside and outside the two sides of the rendering of the map occupies the center, the upper left corner of the brand Logo Xunfei, the lower right corner of the product name is the Xunfei intelligent headset iFLYBUDS. iFLYBUDS".
On the side of the box, there are three product features: real-time call transcription, intelligent dialing recognition, and call translation comparison.
The bottom of the box shows the barcode and product information. The product name is iFLYBUDS, the product model number is XFXK-A01, and there is only one color scheme, white.
On the back of the box, there is a picture of the status of the headset inside the charging case, and below that is the accessory information and some product information. Input power 5V 0.5A, output power 5V 0.2A. Producer: Tianjin Xunfei Extreme Intelligence Technology Co. Manufacturer: Hefei Star IOT Information Technology Co.
Functions such as intelligent voice need to download the "iFLYBUDS App" to use, there are iOS and Android clients.
Inside the box, headset and charging case, user guide and charging cable.
The charging cable is a USB-A to USB Type-C connector, and the C port supports forward and reverse blind plugging, which is easy to use and can also be used to charge mobile devices such as cell phones.
The charging case is shaped like a pillow, with a bulge in the center extending to the corners. The lid opens with a tiny slit, and there is an indicator light on the inside, which can be seen when the lid is opened or closed.
The green bar of the indicator light guide column.
The headset sits upright inside the charging case.
Information on the inside of the lid: product name iFLYBUDS, model number XFXK-A01, input power 5V 0.5A, output power 5V 0.2A, rated capacity 350mAh.
Pogo Pin on the bottom of the charging cradle for charging the headset.
Back of the charging case showing the pairing button underneath the swivel.
The Type-C charging port is located at the bottom of the charging case, with a metal ring around the periphery of the port to decorate and protect the case.
I love audio.com used ChargerLAB POWER-Z KM001C portable power tester to test the wired charging of KUDA Xunfei Smart Headset iFLYBUDS, with an input power of about 1.9W.
KUDA Xunfei True Wireless Smart Headset iFLYBUDS.
The headset and the charging case*** weigh 48.1 grams.
The charging case alone weighs 39.1 grams.
The left and right earphones*** weigh 9.1 grams. Both the headphones and the charging case are relatively lightweight.
Second, KDDI iFLYBUDS charging case disassembly
First of all, let's disassemble the charging case and take a look at its internal power management system. Pry open the charging cockpit to see the internal structure, there are multiple internal snap fasteners.
The pivot and physical buttons on the back of the charging case.
The metal holder at the charging port.
The structural design of the indicator position with light guide column inside.
A plastic center frame inside the charging case holds the motherboard and battery.
The structure of the back of the charging case shows that the motherboard is fixed to the plastic center frame by four screws.
The PCBA at the bottom of the case is connected to the motherboard through a black FPC, which is fixed with screws.
The indicator FPC on the front of the charging case.
Remove the fixing screws that connect the plastic center frame to the charging dock.
Inside of the charging bay, the lid and the metal pivot are fixed with screws, and there are two larger magnets in the headphone position to attract and fix the headphones.
The internal structure of the charging case.
The soft-packed battery is fixed in the plastic housing, and there is a piece of shock-absorbing foam between it and the charging cockpit housing.
Hall element in the metal pivot position.
The Hall element silk-screened AR9x1. Changes in the magnetic field when the lid of the charging case is opened and closed are sensed by the Hall element, which in turn notifies the charging case MCU and the headset to pair or disconnect with the connected device.
The outside of the plastic center frame is shown.
Inside the plastic center frame.
Higher-cost injection-molded special copper nuts.
The internal circuitry of the charging case. The battery is connected to the motherboard via wires, and multiple PCBAs are connected to each other via black FPC.
The other side of the internal circuitry of the charging case.
Soft pack battery model DN551340V, rated capacity 350mAh/1.33Wh, rated voltage 3.8V.
Integrated Li-Ion protection IC silkscreen printed with 191VBEB.
Connection location on the PCBA where PogoPin is located.
Connection location on the PCBA where the charging port is located.
Connection location on the PCBA where the FPC is located on the motherboard. The connector locations all have a small piece of cushioning foam.
Picking the connector and removing the FPC inside the charging case, with the indicator module still attached.
The other side of the FPC inside the charging case.
Close-up of the two LED indicators, the outside silicone is pasted on the case to avoid light leakage.
The PCBA where the Pogo Pin for charging the headphones is located has an ESD for electrostatic protection.
The other side of the PCBA shows the FPC connection socket in the top right corner.
Close-up of the Pogo Pin that charges the headset.
The PCBA where the Type-C charging port is located, also with ESD for electrostatic protection.
The other side of the PCBA is shown, with the FPC connection socket in the bottom right corner.
The Type-C charging port is protected by a silicone cover on the outside, which provides some protection against dust and water.
The main PCBA circuitry of the charging case is shown, with the positive and negative soldering points of the battery wires on the right side.
The other side of the main PCBA circuitry of the charging case, the circuitry is very streamlined.
The micro button on the back of the charging case. There is a larger rubberized protective cover on the outside.
Maxis MAX77813 synchronous boost converter.
MaxicoM MAX77813 details.
The chip for the silkscreen +ALT KAC is Maxim's MAX20340 , a communication management chip.
Maxim MAX20340 details.
Charging IC with silkscreen MZA 2015.
Voltage regulator IC with silkscreen 33.
Holtek Semiconductor HT32F52253 is a 32-bit high-performance, low-power MCU based on the Arm Cortex -M0+ processor core. This series of microcontrollers can operate at up to 40MHz with the help of a Flash gas pedal for maximum efficiency. Several power saving modes provide maximum optimization with flexibility in terms of wake-up latency and power consumption, and this family of microcontrollers can be used in a wide range of applications such as white goods application control, power monitoring, alarm systems, consumer products, handheld devices, data logging applications, motor control, and more.
Block diagram of the Holtek HT32F52253 chip.
Third, KDDI iFLYBUDS headset disassembly
Here we continue to disassemble the headset part, KDDI smart headset iFLYBUDS headset for the handle type half in-ear design, headset handle and in-ear at the shell between the design of the paragraph sense.
The circular aperture at the top of the headset handle contains a microphone to pick up ambient noise for call noise reduction.
Pressure relief holes in the audio cavity with metal dust mesh.
Pressure relief hole on the inside of the headset and an infrared distance sensor opening for in-ear detection.
Metal dust mesh at the sound outlet to prevent foreign objects from entering.
Two silver charging contacts on the bottom of the headset's stem, and a pickup hole for the talk microphone.
The disassembly of a stemmed headset generally starts from the structure of the in-ear and the bottom of the headset stem.
At the bottom of the headset stem, the talk microphone and charging contacts are connected to the motherboard via an FPC.
The bottom of the headphone stem is filled with a lot of glue.
There is a round PCBA inside the audio cavity, and inside the headphone stem is the battery, which is connected to the motherboard via FPC.
The top of the headphone stem is also sealed with a lot of white glue.
Take out the speaker unit.
The housing at the in-ear is double-layered.
The internal structure of the sound chamber is shown.
Close-up of the speaker unit diaphragm.
The T-iron of the speaker unit, soldered to the motherboard.
The moving coil speaker unit is 14mm, as officially advertised.
The dual-layer structure of the housing at the separate ear.
Pressure relief hole and transducer window.
Infrared distance sensor for in-ear detection, connected to the motherboard via FPC.
Close-up of the infrared distance sensor.
Removing the sealant on the top of the headphone stem. The black color on the inside of the case is the magnet that attracts the charging cockpit.
Connector to the antenna FPC.
Disconnect the antenna, and underneath the PCB sub-panel is the call-canceling microphone. The microphone is isolated from the battery with black insulating foam.
Remove the sealant at the bottom of the headset stem to reveal the battery positive and negative soldering subplates, and disconnect the negative battery terminal for further disassembly.
Violently dismantle the headset stem to see the internal structure.
Remove the FPC-style antenna attached to the battery.
The other side of the antenna is shown.
The positive and negative poles of the cylindrical Li-ion battery are connected to the motherboard via FPC.
Positive terminal of the battery.
Size of the cylindrical Li-ion battery compared to a dollar coin.
Removing the insulating film on the outside of the battery.
The supplier of the cylindrical lithium battery is from VDL Chongqing Zijian, with a capacity of 31mAh/0.119Wh and a rated voltage of 4.4V.
According to my love of audio network disassembled to understand, at present, there have been Huawei, Xiaomi, Meizu, OPPO, Birdie audio and other well-known brands in large quantities to use Zijian electronic battery.
The internal structure of the headset is shown in full.
The shell at the bottom of the headset handle, using a lot of sealant to reduce the chance of water ingress.
The internal circuitry of the headset is shown. An entire FPC is connected to the motherboard circuitry, speaker unit, infrared distance sensor, antenna, dual microphone array, and cylindrical Li-ion battery.
The other side of the headset's internal circuitry.
The size of the headphone's motherboard compared to a dollar coin.
An adhesive pad between the motherboard and the speaker unit.
The main control chip and related circuitry is shown.
Circuitry display on the other side of the motherboard. Silkscreened 1M AMAPH is the MCU from Ambiq Micro.
ICs silkscreened Z7CLW and memory silkscreened 0358GK.
The ST STMicroelectronics LIS2DW12TR, an ultra-low-power accelerometer sensor with a 98% knock recognition rate, has been used in numerous headphone brands.
According to I love audio network disassembly to understand, including Apple, Amazon, Samsung, millet, vivo, go out to ask the brand's flagship TWS headset are a large number of ST STMicroelectronics sensors.
Pogo Pin at the bottom of the headset.
MEMS silicon microphone of Radium 056 OVF, which is mainly used to pick up the human voice during calls.
Solder joint for the negative battery terminal.
Contacts for the positive battery terminal.
The microphone used to pick up ambient sounds, with a dust mesh on the outside.
MEMS silicon microphone for the Radium 056 OVF, mainly used to pick up ambient noise.
Antenna connector to the main FPC.
Battery protection circuitry sealed with glue.
Silkscreen 9x4G all-in-one Li-Ion protection IC.
Maxim Maxis MAX20340, communication-cum-charging management chip.
Disassembled family photo.
I love audio summary
iFLYBUDS, Xunfei's first true wireless headset, has a more personalized look, with a charging case shaped like a pillow, with the middle bulging out to the corners, and the headset is a half-in-ear design, with segments between the headphone handle and the shell at the ear, looking like a patchwork, which is more distinctive. The headset and charging case are lightweight and easy to wear and carry.
In terms of internal circuitry, the KDDI iFLYBUDS charging case has a plastic center frame to hold the battery and multiple PCBAs, with FPC connections between the PCBAs. The charging case inputs power through the Type-C port, there is a Maxis MAX77813 synchronous boost converter and a charging IC, Maxis MAX20340 is responsible for the communication between the charging case and the headset, and the soft-packed battery has a capacity of 350mAh; there is a Hall component in the charging case for the open-cap-as-a-connector function, and the Hoptech Semiconductor HT32F52253 low-power MCU is used for the whole control of the machine, and the circuit is The circuitry is streamlined.
KU Xunfei iFLYBUDS headset for the handle half in-ear design, headset handle is Chongqing Zijian steel shell cylindrical lithium battery, capacity of 31mAh, the battery positive and negative through the soft wiring connected to the headset within the main FPC; headset FPC antenna pasted on the battery, through the connector connected to the main FPC. In addition to this, this FPC inside the headset is connected to the main board circuitry, speaker unit, infrared distance sensor for in-ear detection, and dual microphone array for call noise cancellation.
The headset's main controller chip is a flagship audio SoC, which ensures stable information flow when the headset is used for call recording, real-time transcription, and assisted translation, while the chip architecture is designed for low power consumption, with 4 hours of music life and 2 hours of call+recording+transcription life. There is also an Ambiq Micro MCU inside the headset, an STMicroelectronics accelerometer for detecting knock status, and dual MEMS silicon mics for call noise reduction.
In terms of details, KDDI iFLYBUDS also handled very well: the charging port has a metal ring around the periphery to increase durability, and a dustproof and waterproof adhesive ring on the inner side; the plastic center frame inside the charging case uses a high-cost injection-molded special copper nut to fix the motherboard; the charging case has cushioning foam on the internal FPC connections, and there is also a dustproof and waterproof protective cover at the pairing buttons, and the indicator light position is also very well designed. The design of the indicator light position is also very attentive; the internal structure of the headset is sealed independently of each other, using a large number of sealant to protect against dust and water, and is not easy to dismantle.
From the hardware level of disassembly, iFLYBUDS, as the first true wireless headset from KUDA Xunfei, uses better materials and solid workmanship, which is the level of the flagship product at this price point, and is suitable for business people who often use cell phone calls, and are accustomed to recording important voice content.