Introduction

ST72681

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Introduction

The ST72681 is a USB 2.0 high-speed Flash drive controller. The USB 2.0 high-speed

interface including PHY and function supports USB 2.0 mass storage device class.

The mass storage controller interface (MSCI) combined with the Reed-Solomon

encoder/decoder on-the-fly correction (4-byte on 512-byte data blocks) provides a flexible,

high transfer rate solution for interfacing a wide of range NAND Flash memory device types.

The internal 60 MHz PLL driven by the 12 MHz oscillator is used to generate the 480 MHz

frequency for the USB 2.0 PHY.

The ST7 8-bit CPU runs the application program from the internal ROM and RAM. USB data

and patch code are stored in internal RAM.

I/O ports provide functions for EEPROM connection, LEDs and write protect switch control.

The internal 3.3 to 1.8 V voltage regulator provides the 1.8 V supply voltage to the digital

part of the circuit.

Figure 1.

Device block diagram

USB 2.0

USB 2.0

Function

Mass

Controller

PHY

Storage

Interface

Reed-

Solomon

Error

Correction

NAND

I/F

8-bit

CPU

ROM

RAM

3.3 V to 1.8 V

voltage

GPIO

12 MHz

OSC

regulator