Samsung S23 Ultra SM-S918B EMMC ISP PinOUT

The Samsung S23 Ultra SM-S918B eMMC ISP Pinout is essential for advanced repair and flashing procedures, especially when dealing with issues like dead boot, FRP lock

or firmware corruption. This pinout allows you to interface directly with the eMMC/UFS chip without removing it from the board, providing a reliable solution for tasks such as data recovery, firmware dumps, and partition repairs. The ISP points are typically found near the eMMC chip under the metal shield, and careful identification is key.

The required connections are:

• CLK (Clock)
• TXOP (Transmit Data Out Positive)
• TXON (Transmit Data Out Negative)
• RXOP (Receive Data In Positive)
• RXON (Receive Data In Negative)
• GND (Ground)

Post Index:Samsung S23 Ultra SM-S918B EMMC For a seamless repair process, tools like UFI Box, Easy JTAG, or Medusa Pro are necessary to interface with the chip. Once correctly connected, these tools allow you to perform various operations, including unlocking FRP, flashing firmware, or restoring a corrupted boot. Always ensure a precise connection to avoid damaging the motherboard, and use a magnifier to confirm the ISP pinout. With the right setup, this process enables you to revive the device without the need for a full teardown or chip removal.

In this post, I'll guide you through the ISP Pinout for the Samsung Galaxy S23 Ultra 5G (SM-S918B) mainboard. Using this pinout, you can put the device into EDL mode, perform dead boot repairs, unlock FRP, flash firmware, or recover data with tools like Easy JTAG, UFI, or Hydra. I'll also share tips on the tools you'll need, how to make the connections, and common fixes based on hands-on experience.

⚙️ What is ISP (In-System Programming)?

Simply put, ISP lets you access the Samsung S23 Ultra SM-S918B EMMC or UFS chip without needing to remove it from the board. All you need to do is identify the correct pinout on the motherboard and connect it to a supported tool like UFI, Easy JTAG, or Medusa Pro. This allows you to directly interface with the chip for tasks like flashing, data recovery, or repairs.

The ISP Pinout is useful in situations like:

The phone is dead (black screen, no boot, no charging)

FRP is locked, and ADB, fastboot, or OTG bypass won’t work

Also read: Samsung A05 SM-A055F/M EMMC ISP Pinout

You need to dump firmware from a working device to repair a dead one

You’re performing a boot repair or restoring partitions

The phone is detected as "unknown" on the PC, and EDL mode isn’t functioning

Samsung S23 Ultra SM-S918B UFS ISP Pinout Image:

Now, let’s get into the technical details. The Samsung S23 Ultra SM-S918B EMMC shares a similar hardware layout with several other models, but the pin locations may vary slightly. The ISP points are typically located near the UFS chip, under the metal shield.

Key UFS ISP Pin Labels:

CLK

TXOP

TXON

RXOP

RXON

GND – Ground

💡 Tip: To correctly identify these points, use a microscope or a 10x magnifier. Don’t rely solely on diagrams—always verify the layout visually. When dealing with dead boot issues, especially on devices like the Samsung S23 Ultra SM-S918B, tools like the Easy JTAG Plus and UFI Box dongles are essential. They are particularly useful in cases where the phone has been incorrectly flashed, fails to display the startup logo, or is completely unresponsive to power.

Required Tools for ISP Pinout:

Before you begin, ensure your bench is properly set up with the following tools:

UFI Box, Easy JTAG, or Medusa Pro

0.1mm – 0.3mm Jumper Wires

Fine Tip Soldering Iron

Isopropyl Alcohol (IPA 99%)

Soldering Flux

Multimeter (for checking continuity)

How to Connect ISP to eMMC Box:

Remove the battery from the phone – this is crucial to avoid voltage conflicts.

Clean the PCB area using isopropyl alcohol to remove any dust or residue.

Carefully solder jumper wires to the following points on the motherboard:

CLK

TXON

TXOP

GND

RXON

RXOP

Connect the wires to your UFS/eMMC tool, following the pinout specific to your tool.

Double-check each connection using a multimeter to ensure there are no shorts between the wires.

Connect to UFI or Easy JTAG.

In the UFI or Easy JTAG Software:

Select "Identify UFS eMMC" from the software interface.

Choose the operation you need:

User Partition

Also read: Samsung M35 5G M356B ISP Pinout Solution

Special Task

Reset FRP

✅ If the connection is correct, you will see the UFS chip information displayed in the tool window.