Phison PS2303 (PS2251-03)

PS2303 is a low cost USB3.0 NAND controller used in many modern USB flash drives. Description at Phison's site.

Two packages available:

• LQFP64 (PS2251-03-Q) - dual channel version
• LQFP48 (PS2251-03-V) - single channel version

Chip architecture

PS2303 consists of:

• 8051-compatible 250MHz (yes, 250 !) core with 256 bytes of IRAM (DesignWare DW8051 ?), two timers
• 256KiB (?) RAM used for code/data/USB buffers/NAND buffers
• USB 3.0 function core (Synopsys ?)
• Two NAND flash interface cores
• NAND data processor (ECC, descrambler)
• DMA core (moves data between RAM/NAND/USB at high speed)

Memory map

• CODE 0000-7FFF(?) - program RAM, mapped to PA (physical address) 0 of RAM. Size can be changed ?
• XDATA 0000-EFFF - data RAM, consists of several independently mapped areas
• XDATA F000-F3FF - USB 3.0 function core
• XDATA F400-F4FF - NFC0 (NAND flash channel 0)
• XDATA F500-F5FF - NFC1 (NAND flash channel 1)
• XDATA F600-F6FF - NDP (NAND data processor)
• XDATA F700-F7FF - NFC0/1 interleaved port
• XDATA F800-F8FF - ?
• XDATA F900-F9FF - DMA
• XDATA FA00-FAFF - SYSTEM (RAM mapping, clocks, GPIO, ...)
• XDATA FB00-FBFF - ?
• XDATA FC00-FCFF - ?
• XDATA FD00-FDFF - ?
• XDATA FE00-FEFF - ?
• XDATA FF00-FFFF - ?

Interrupts

• INT0 - USB control interrupt (bus states, EP0 requests)
• INT1 - Timer 0 overflow interrupt (standard 8051 feature)
• INT2 - USB endpoints interrupt (bulk data available)
• INT3 - Timer 1 overflow interrupt (standard 8051 feature)

USB flash drives based on PS2303:

• Patriot SuperSonic Xpress USB 3.0 - full LQFP64 version for 10EUR price (8GB model)
• Kingston DataTraveller 111 - LQFP48 version
• many others