Silicon Power USB flash drives using the Phison PS2251-16 (PS2251-162)
You have already identified the controller as (often displayed as PS2251-16(PS2251162)). This is a Phison controller. The specific tool required for this chip is the Phison MPALL tool. formatter silicon power v3700 ps2251162 best
If your Silicon Power V3700 shows as (Zero Bytes) in Disk Management, the controller is in "Boot Mode." MPALL cannot see it, but ST-Tool can. Use ST-Tool with the "Preformat" option to force the drive back to operational mode. Silicon Power USB flash drives using the Phison
Plug in your USB drive, wait for the tool to recognize it, and click the Silicon Power Troubleshooting Tips Not Detecting: Windows (GUI): Plug in your USB drive, wait
Click to confirm the tool sees your controller (PS2251-16).