G2 form factor solid-state USB flash drive SM2246XT-M-AA, four-layer PCB

  Hello! This is Lost_Terminal! ヾ(≧▽≦*)o I'm so glad you found this project!
  This is probably my first bold attempt, and I didn't expect it to actually work.
Enough with the chit-chat, let me briefly introduce the board:
  • This is a solid-state USB flash drive based on the SM2246XT-M-AA controller (QFN88 package). Its main components are a USB-to-SATA bridge, a SATA SSD controller, and NAND flash memory chips.
  • The bridge chip is ASMedia ASM1153e, supporting USB 3.2 Gen1 (5Gbps) → SATA3 6Gbps, offering excellent compatibility.
  • The flash memory pads are single BGA152 pads (compatible with BGA132, BGA108, BGA88, etc.), supporting dual channels for a total of 4CE. The data cables have been lengthened.
  The power supply chips used are the common MP2122 and RT8010, which are readily available on the component board, providing continuous dual-channel 2A (VCCF, VCCFQ) and single-channel 1A (Core) power respectively.
  The smallest component package is 0402, reducing the difficulty of manual soldering; all NAND flash pads are retained to ensure strong soldering.
  The board size is a standard G2 form factor, with the mounting slots on both sides intact. An indicator light is provided on both the front and back; the front one is the bridge indicator, and the back one is the 2246XT indicator (RDT also flashes). The board is
  compressed to a four-layer design, achieving the lowest possible cost and thickness. The via sizes are 0.5/0.3mm, and the USB connector pins are full length.
  Due to its small size and the fact that the 2246XT uses an older 55nm process, it will generate some heat, especially when paired with Intel and Micron (IMFT) NAND flash chips. A metal casing with thermal pads is recommended.
  The board has three pre-installed jumpers: TOG (R23), R46, and VCCQ1.8. R23 and R46 are both 10K resistors, and VCCQ1.8 is a 0-ohm resistor. Functionally, R23 is the Silicon Motion Toggle jumper, required when using Toggle-based chips. R46 is the reliability mode jumper, required when using certain Toshiba/SanDisk 15nm MLC chips. When VCCQ1.8 is shorted, the VCCQ voltage of the chip is 1.8V; when not shorted, the VCCQ voltage is 3.3V. Adjust accordingly based on the specific situation.
  This concludes the basic overview of the board. Regarding why I designed this board when there are already more mature dual-G2 2246XT boards on the market, it's because no one has designed a USB flash drive controller board for this crippled version of the QFN88 2246XT (only supporting 2CH4CE). Furthermore, this controller is somewhat unsuitable as an SSD controller, but perfect as a USB flash drive controller, so I designed this board.
*Waiting for the board to arrive .
After receiving the board, I started soldering:
I didn't have many good NAND flash chips, so I could only find this S9-grade PF026 large S NAND flash chip for testing:
Normal ID recognition upon system boot
: Card activation
: Partitioning:
Simple speed test:
Eye test:
urwtest full disk speed test, showing no speed drop across the entire disk:
Flashing the bridging firmware:
High load temperature of the bare board (with IMFT L85C process NAND flash chips):
That should be about it. I think I've covered everything. (
In short, this is the board. Feel free to ask any questions in the comments section.)
Sponsored by: EVAStudio→evassd.cn