Yesterday, Xiaomi launched the MIX 4. After three years of development, Xiaomi’s first under-screen camera phone has finally been launched. A blogger quickly posted a teardown video of the phone, revealing its internal structure, components, and technological secrets.
The Xiaomi MIX 4 uses an integrated lightweight ceramic body. Of course, to ensure signal reception, a very narrow metal frame is retained between the screen and the ceramic, with reserved areas for the antenna.
The first step of disassembly is to power off the phone and remove the SIM card tray. Then place it on a 90°C heating pad or use a heat gun to heat it up, and gently pry open the gap with a thin tool. When separating the back cover from the screen, be careful with the USB-C cable at the bottom to avoid breaking it.
This phone uses a common three-section structure. The upper part contains components such as the SoC, camera, memory, and UWB antenna; the middle part includes the NFC module, wireless charging coil, and dual-cell battery; the lower part is a sub-board that integrates the speaker, linear motor, USB-C port, and other modules.
The Xiaomi MIX 4’s cooling system uses a large amount of thermal film, copper foil, and thermal paste on the chip. Tests show that after playing ‘Honor of Kings’ for half an hour, the device’s average temperature is 36°C; after playing ‘PUBG Mobile’ for half an hour, the average temperature is 39°C.
The LPDDR5 memory of the Xiaomi MIX4 comes from Samsung, the ROM from SK Hynix, the battery from Dongguan New Energy, and the speakers and microphones from AAC Technologies.
Regarding the under-display camera, under strong light, two light-transmitting holes are visible on the top of the device: the circular hole is for the front camera, and the square hole is for the distance/ambient light sensor. The front camera has a higher light transmittance.
In addition, although Xiaomi claims that the Xiaomi MIX 4 supports 50W fast charging, actual tests show that when paired with the wireless charging dock, it can reach 100W, fully charging in just 36 minutesIn addition, although Xiaomi claims that the Xiaomi MIX 4 supports 50W fast charging, actual tests show that when paired with the wireless charging dock, it can reach 100W, fully charging in just 36 minutes, and 120W fast charging can fully charging in 20 minutes.
