Preface
Charging head network has purchased a new generation of Lefen sweeping electric toothbrush, which supports 60° sweeping brush and is ergonomically designed. The handle of the toothbrush is lightweight, short and lightweight, and is sprayed with UV gloss paint to improve the tactile feel and clean better. Seamless pressure-sensitive buttons on the toothbrush handle enhance the user experience.
The toothbrush uses magnetic charging, and uses a Type-C interface, a universal mobile phone charger. The brush handle has 2 built-in batteries, and with the self-developed servo system of Leifen, the driving force is increased by 300%, and the vibration frequency is up to 66,000 times per minute. The PID dynamic compensation algorithm is also used to solve the attenuation problem. Let's bring the disassembly of this sweeping electric toothbrush, and take a look at the internal materials and design.
Unboxing of the Lefen sweeping electric toothbrush
The front of the box is printed with a drawing of the main body of the product.
The bottom is printed with information such as the packaging list, specifications, merchant and production date.
Magnetic charging cable, brush head and product manual at a glance.
The magnetic charging cable is a braided cable, which is fixed in a similar way to Apple's.
Close-up of the inside of the USB-C male with full PIN design.
The magnetic terminals have a metal housing and three gold contacts at the front.
The standard gum guard brush head, the high-efficiency cleaning brush head, and the light white brush head are all in one package.
The brush head is made of imported DuPont brush filament, which has passed the TUV Rheinland certification.
The body of the Leifen sweeping electric toothbrush is available in white, blue, purple and other colors, with an overall lightweight design, and the surface is sprayed with UV glossy paint, so that the body has a ceramic touch and a better user experience.
The top output shaft is protected by a plastic case.
The top is also designed with a waterproof structure to achieve an IPX7 waterproof rating, which is not afraid of water splashes.
Short press the power button on the fuselage to power on, double press to switch modes, and press and hold to unlock the airplane mode. At the same time, the power button is designed with seamless pressure sensitivity, which can effectively avoid dirt and dirt.
The fuselage is equipped with a gear indicator, an airplane mode indicator, and a battery indicator, which is a hidden design.
There is a charging contact in the center of the bottom of the fuselage, and the product parameter information is printed on the periphery, the model is LFTB01-P, the working power is 6W, the working voltage is 7.6V, the rated charging input is 5V1A, and the battery capacity is 900mAh.
To charge the Laifen sweeping electric toothbrush, the measured output power of the charger is 5.12V 0.78A 3.97W.
Leifen sweep electric toothbrush disassembly
After reading the unboxing and display of this electric toothbrush, let's disassemble it and take a look at the internal materials and design.
First, pry open the bottom cover of the electric toothbrush, and the edge of the cover is provided with a rubber seal.
Open the caseback to extract the internal movement.
Remove the inner movement of the brush handle and fix it in its entirety with a plastic frame.
Close-up of the waterproof structure inside the shell.
Close-up of the waterproof rubber ring on the bottom cover.
The bottom ejector pin is soldered to a small PCB and connected to the movement by wires.
The movement is constructed with a frame structure with a PCB on one side and a battery pack and permanent magnet motor on the other.
From the side, the permanent magnet motor is connected to the PCB via a cable.
The motor and battery pack on the back are fixed inside the plastic frame, and the Leifen brand is printed on the motor.
Close-up of the motor output shaft, secured to the frame by screws.
Close-up of the socket at the bottom of the handle where the battery is attached.
Split the connection of the motor and battery to the PCB.
The solder cable at the tail of the motor is connected to the PCB board, and the battery is also connected with a plug-in bracket.
The motor housing is printed with the words "laifen Dongguan Laifen manufacturing DAAJH1B21".
The cable is connected to the motor coil by welding and fixed with screws.
The battery pack is fixed with a plastic frame, and foam double-sided tape is pasted on the surface of the battery to cushion.
Close-up of double-sided tape glued to the side of the battery.
Close-up of double-sided tape glued to the bottom of the battery.
The battery pack is connected in 2 strings, the nominal voltage of the battery pack is 7.6V, the charging limit voltage is 8.7V, the rated capacity is 900mAh, and the rated energy is 6.84Wh, which comes from Dongguan Xindian Energy Co., Ltd.
The size of a single cell is 9mm thick, the width is 18mm, the length is 47mm, and the battery voltage is 3.8V, which belongs to the high-voltage battery.
The battery is equipped with a protective plate, and the protective plate components are glued and sealed.
Battery protection chip silk screen printing PHCK.
Battery protection tube silk screen 8205A.
The protection plate is equipped with a resettable fuse for overcurrent protection.
The front of the PCB is at a glance, with a Bluetooth chip on the left side, a chip inductor, a charging chip, an indicator light, an indicator driver chip, and a main control MCU to the right. In the middle are the three MOS tubes and current detection resistors of the drive motor, and on the right are the light-sensing pressure button chip and the power indicator.
There are no components on the back of the PCB, and the plastic frame is glued using double-sided tape.
The input over-voltage protection chip is from Yutai Semiconductor, model ETA7014, silk-screen MA, which is a high-side over-voltage protection chip, the protection point is adjustable, the maximum withstand voltage is 36V, the internal resistance is 35mΩ, and it supports over-temperature protection for input over-voltage protection.
E-Tech Semiconductor ETA7014 Profile.
A screen-printed CCE TVS diode is used for overvoltage protection.
The battery charging chip is from Yingjixin, model IP2326, which is a 2/3 string lithium battery boost charging IC with integrated charge balancing function, with integrated 500KHz synchronous rectification boost, and can dynamically adjust the input voltage according to the battery voltage to optimize the boost conversion efficiency.
Yingjixin IP2326 supports charging status indication. The input withstand voltage is 25V, supports NTC battery temperature detection, supports input undervoltage, overvoltage protection and charging timeout protection. IP2326 provides charge equalization when used for 2-string charging.
Yingjixin IP2326 data information.
The main control MCU of the toothbrush comes from Lingou Chuangxin, the model is LKS32MC084DF6Q8, the chip integrates 96MHz main frequency, 32-bit Cortex-M0 core, and integrates the special DSP for motor control with independent instruction set, and the built-in three-phase full-bridge bootstrap gate driver can directly drive 6 NMOS for three-phase brushless motor drive.
凌鸥创芯LKS32MC084DF6Q8资料信息。
The MOS transistor used to drive the brushless motor is from Changjing Technology, model CJBM3020, dual NMOS, internal half-bridge connection, withstand voltage 30V, conduction resistance 8.5mΩ, and DFNWB3*3-8L-BE package.
The step-down chip comes from Xinyuan Semiconductor, silk-screen FN, the actual model is MP2322, which is a synchronous step-down chip with a built-in switch tube, with an output current of 1A, and is packaged in QFN-8.
The driver used to drive the RGB LED indicator is from Herun Electronics, model HTR3212, which is a 12-channel LED driver for toothbrush handle light control.
Close-up of the accelerometer chip for picking up the wake-up function,
The Bluetooth chip is from Fengjia Technology, model PHY6222, is an ultra-low-power SOC that supports Bluetooth BLE5.2 and IEEE 802.15.4 communication protocols, integrates a multi-mode RF transceiver inside the chip, and is equipped with a 32-bit ARM Coretx-M0 processor.
Close-up of SMD ceramic bluetooth antenna.
A silk-screen FMS-033QA chip is used for key operation detection.
Close-up of the infrared emitter and receiver tube used for key-operated detection.
A list of all dismantling and a family photo.
Summary of the dismantling of the charging head network
The Laifen Sweeping Electric Toothbrush has a built-in high-performance self-developed servo system and a high-energy-density battery, which fully unleashes performance and improves the consumer experience. The handle of the toothbrush is charged magnetically, which reduces the cost of ownership for consumers. The included magnetic charging cable is a USB-C port, which can be used to charge the toothbrush with a mobile phone charger. The toothbrush handle also features seamless pressure-sensitive buttons for a better user experience.
Through dismantling, the charging head network learned that the Laifen sweeping electric toothbrush has a built-in two strings of lithium battery packs, and the battery pack comes from Dongguan Xindian Energy Co., Ltd., which is a high-voltage lithium battery. The toothbrush PCB is ETA7014 by Yutai Semiconductor for input overvoltage protection, and the Yingjixin IP2326 chip is used to boost the voltage to charge the second string of lithium batteries.
The toothbrush handle has a built-in Lingou Chuangxin LKS32MC084DF6Q8 MCU for brushless motor operation control, Fengjia Technology PHY6222 for Bluetooth connection, Herun electronic HTR3212 for lighting control, and an acceleration sensor for picking up and waking up function.