Everyone has a drawer of retired phones: cracked screens, swollen batteries, boot loops that take forever. Most of them end up sold for pocket change, traded for a stainless steel basin, or left to gather dust. But inside that "e-waste" hides a genuinely capable component — the eMMC or UFS storage chip on the mainboard, which is essentially a high-performance flash memory. With a little soldering, that chip becomes a custom USB drive that reads faster than most store-bought sticks.
The whole project costs about 30 yuan (~$5) in parts. Here is how it works, step by step.
Step 1: Remove the "Retired" Chip
Start by heating the phone's back cover — a hairdryer on hot, circled over the panel for about a minute — then work the seam open with a suction cup and a plastic spudger.
The first rule is safety: disconnect the battery ribbon cable before touching anything else. Then find the black square chip on the mainboard stamped with a "Samsung", "Toshiba", or "SanDisk" logo — that is the eMMC or UFS storage. It sits surrounded by a crowd of tiny resistors.
Use a hot-air rework station set to around 350°C at moderate airflow, sweep the nozzle around the chip's edges for about 40 seconds until the solder melts, and lift it free with tweezers.
No hot-air station? There is a "soft mod" alternative: buy a matching no-solder USB controller board, read the chip's info through a data cable, and mount the whole mainboard inside an acrylic enclosure. It works, but it skips the fun.
Step 2: Give the Chip a New Home — Solder It to a Controller Board
Order a matching USB flash controller board — common options are the NS1081 or SM3350, and the chip protocol must match. You will also need a fine-tipped soldering iron, flux, and 0.3 mm solder wire.
Apply a thin coat of flux to the chip's pads, align it with the board's pad markings (usually a small dot marks pin 1), and drag-solder around all four sides. The molten solder will distribute evenly under surface tension. If neighboring pins bridge, a bit of solder wick cleans them up.
This step tests patience — but when the four sides gleam silver under a magnifier, the payoff is real.
Step 3: Plug In and Rebuild the Drive's Identity
Insert the controller board into a USB port and the system will detect new hardware. Open the mass-production tool (usually provided by the board seller), let it identify the chip capacity, set the drive name, and hit Start. When the progress bar finishes, a dead phone chip officially has a new life as a USB drive.
Performance is the pleasant surprise: a typical eMMC 5.1 chip reads around 150 MB/s and writes about 40 MB/s — roughly three times faster than an ordinary USB 2.0 stick. Large file transfers stop being a chore.
