Where is the memory physically located in the smartphone Xiaomi Redmi 9: disassembly, schemes and nuances

Why it’s important to know the location of memory in Redmi 9

Xiaomi Redmi 9 (codenamed lancelot) has become one of the most popular budget devices of 2020 due to balanced specs and price. However, over time, users face problems from slow operation to complete drive failure. Knowing the physical location of the memory chip on the motherboard will help in troubleshooting, replacing components or recovering data.

In this article, we will look at where the eMMC (or UFS in some versions) is located in Redmi 9, how to identify it visually, and what to do if it fails. This information will be useful for both users and repairmen. For clarity, we will provide photos of the boards with the exact coordinates of the chip, as well as diagrams of pins.

Note that this is about the physical location — not how to see the amount of memory in the settings, but where the chip on the board is located, which is critical for cases where you need a soldering station, a programmer or a replacement component.

Memory specifications in Redmi 9: eMMC vs UFS

Before looking for a chip on the board, it is important to understand what type of memory is used in your modification of the Redmi 9.The smartphone was produced in several variations, and not only the performance, but also the appearance of the chip depends on this:

• 📱 Basic version (2/32 GB, 3/32 GB, 3/64 GB): eMMC is used 5.1 from manufacturers Samsung, Hynix or Micron. read/write speed - up to 250/125 MB/s.
• 🚀 Redmi modification 9 Prime/9T (4/64 GB, 4/128 GB: in some lots, the UFS 2.1 (For example, Samsung chips KLUFG8UHED). Speed to up. 850/250 MB/s.
• ⚠️ Chinese versions (Redmi 9 China): can be equipped with both eMMC and eMMC UFS party-wise.

How do you determine what type of memory is in your device without disassembly?

1. Install the AIDA64 or CPU-Z app.
2. Go to the Memory or Storage section.
3. See the line Drive Type: If you have an eMMC or UFS, that’s your option.

If you have UFS, the chip will be smaller and with different pin locations, which is important to consider when searching the board.

Redmi 9 Disassembly: How to Get to the Motherboard

To see the memory chip, you need to completely disassemble the smartphone, and this process requires caution: the plastic latches are fragile, and the plumes are easily damaged.

1. Turn off the phone and remove it. SIM-scatter-card.
2. Heat the back cover with a hair dryer (~60°C) around the perimeter to soften the glue.
3. Put a plastic blade on the lid (metal tools will leave scratches!) Start at the bottom edge where the charging connector is located.
4. Disconnect the battery plume by pulling the black tongue (don't pull the wires!).
5. Unscrew 10 Phillips #00 screws that fix the metal plate over the motherboard.
6. Remove the plate and gently disconnect all the plumes (camera, display, power button).

Now the motherboard is free, and it can be removed or left in the case for inspection.

⚠️ Warning: If you've never taken a smartphone apart, you should contact the service. Damage to the display plume or the breakup of contact areas on the board can make the phone non-repairable. It's especially risky to work with the Redmi 9 because of the fragile battery connector.

Localization of memory chip on the Redmi 9 board

On the Redmi 9 motherboard, the memory chip is located on the front side (the one facing the screen when it is built).

• 📍 Location: Top right corner of the board, next to the MediaTek Helio processor G80 (marking MT6769).
• 🔍 Appearance: For eMMC: a rectangular chip size ~12×14 mm, 156 Contacts (marking: Samsung) KLMBG, Hynix H9HKNN, Micron MTFC). For UFS: square-chip ~11×11 mm, 162 contact (marking: Samsung) KLUFG, SK Hynix H28U6).
• 🎯 Guide: Look for a chip labeled eMMC or UFS Next to a metal screen that covers the processor.

Below is a table with visual differences between memory chips depending on the manufacturer:

Photo of the boards indicating the memory chip:

(There should be marked images here, but we'll describe details in text format.) On the Redmi 9 board, the memory chip is located to the left and just below the CPU. It is usually closed with a heatpaste or heat pad (in UFS models). If there are chips or blackened chips, this is a sign of overheating or short circuit.

Diagnosing Memory Failures: When Replacement Is Needed

If the smartphone slows down, reboots spontaneously, or doesn't turn on at all, the problem may be in memory. eMMC/UFS:

• 🐢 Extremely slow: applications open for a long time, files are copied at a speed of 1-5 MB / s.
• 🔄 Cyclic reboots: phone goes to bootloop (hang on Redmi logo).
• 🚫 Read/write errors: Memory is damaged or "SD-The card is not supported" (even if it is not available).
• 📵 Not turned on: the screen remains black, but there is vibration when you press the buttons.
• 🔋 Fast battery discharge: damaged memory can cause increased power consumption.

For diagnosis, use:

1. PC test: Connect your phone in Fastboot mode and execute the command: fastboot devices fastboot getvar all If the answer has the lines mmc0: error or ufshc: fail - a problem in memory.
2. Check through Recovery: Go to the Recovery (Power + Vol Up) and select Mount. If the /data partition is not mounted, the memory is damaged.

⚠️ Note: If the phone does not turn on, but when connected to charging, the area next to the memory chip warms up - this is a sign of a short circuit in the power chains eMMC/UFS. In this case, self-repair is dangerous: a diagnosis is required for USB-oscilloscope.

Replacement of memory in Redmi 9: what you need to know

Replacing a memory chip is one of the most difficult tasks in smartphone repair.

• 🔧 Tools: soldering station with thermal air (for example, Quicko) T12), flux RMA-223, solder Sn63Pb37, tweezers, magnifying glass.
• 🛠️ Donar or new chip: Must be identical to the model (for example, if there was a Samsung) KLMBG8WEJD, replace it with one).
• 💾 Firmware and programmer: for eMMC, EasyJTAG or Medusa Pro is suitable for UFS — UFI Box.

Step-by-step process:

1. Remove the old chip by heating it on both sides with heat air (temperature ~350°C). Use low airflow to keep the small elements from blowing away.
2. Clear contact areas from solder residues using swab and flux.
3. Set the new chip together, pin it with a flux drop, and solder it neatly, heating it around.
4. Connect the board to the programmer and flash the memory dump (if there is a backup) or clean firmware.

The cost of replacement in the service: from 3 000 to 8 000 rubles (depending on the type of memory and region). Self-repair will cost 1,500-3 000 rubles (chip price + consumables), but the risk of damage to the fee is high.

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Before you change your memory, make sure to back up the data via ADB (if the phone is still on) or with a programmer in SLOT1 mode. Even if the chip is damaged, you can sometimes pull some data out.

Frequent errors when working with memory Redmi 9

Inexperienced craftsmen often make critical mistakes that lead to complete data loss or board failure.

• 🔥 Overheating board: temperature above 380°C destroys multilayered tracks. Always use the thermocouple to control.
• ⚡ Static electricity: discharges can kill a memory chip or processor.
• 🔄 Incompatible chip: Even if the eMMC looks the same, the internal architecture may be different. For example, Hynix eMMC is not always compatible with Samsung eMMC of the same capacity.
• 📱 Damage. BGA-And the only way to get the chip off is to break off the contact pads, and you can only restore them with a microscope and hair wires.

If the phone is not switched on after replacement:

1. Check the memory power circuit with a multimeter (voltage on the capacitors next to the chip should be ~1.8V for eMMC or ~3.3V for UFS).
2. Make sure the firmware is suitable for the new chip (for example, UFS requires firmware with support for UFS drivers).
3. Check logs via fastboot oem dump-memory for initialization errors.

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If the phone turns on after the memory change but does not see the internal drive, the problem is incorrect firmware or damaged partitions (for example, EFS or MODem), in which case a full rebuilt partition of the userdata through the programmer is required.

FAQ: Answers to Frequent Questions