Cracked MicroSD Card Data Recovery: Full Walkthrough
A 128GB SanDisk microSD card with scratched contacts that broke critical signal traces. This 75-minute video covers the entire recovery pipeline: trace repair via micro-soldering, direct NAND access through a VNR reader, monolithic controller identification from page structure and ECC patterns, bad column detection, XOR decryption, and data reconstruction.
Trace Repair: Reconnecting Broken Signal Paths
Microscope examination showed scratches had severed several PCB traces under the contact pads, including power, clock, data, and command lines. Any one broken trace is enough to make the card invisible to every device.
The repair involves scraping the protective coating to expose underlying copper, then soldering hair-thin wires across each break at around 350 degrees C. After soldering, resistance measurements confirm continuity on each repaired trace. In this case, even successful trace repair was not enough; the card's response pattern indicated the controller itself was compromised, requiring direct NAND access.
Direct NAND Access and Controller Identification
MicroSD cards are monolithic: the controller and NAND memory are sealed together in a single inseparable package. When the controller is dead, you bypass it by soldering wires directly to the NAND memory pins, consulting a pinout database to find the correct configuration, then connecting through a 2-channel VNR reader.
Getting a valid chip ID back confirms the NAND is alive and the connections are correct. The next challenge is identifying the controller, since it is hidden inside the sealed package. The video demonstrates this by analyzing the NAND page structure: the layout of user data, service area, and ECC bytes is unique to each controller manufacturer. ECC pattern matching confirmed a Phyzen-based controller, which determines the XOR key needed to decrypt the data.
Bad Column Removal and Data Reconstruction
Raw NAND dumps contain defective columns: vertical sections of cells that are permanently broken and corrupt the same bit position in every row. The VNR software detects these by looking for repeating corruption patterns across all planes.
This card had 4 planes and 3 distinct bad columns. The software also discovered that the logical block size was half the physical block size, requiring the structure to be doubled during mapping. After bad column removal, XOR decryption with the Phyzen key, and ECC correction, the software reconstructed the logical file system from the corrected raw data.
The full 128GB NAND read took over 12 hours and was left running overnight. This is standard for large-capacity monolithic recoveries.
MicroSD Card Not Recognized?
Scratched contacts and dead controllers do not mean the data is gone. The NAND cells inside may be intact. Send it in for evaluation before corrosion or further handling makes things worse.