GENERAL DESCRIPTION
   The W28V400B/T Flash memory with SmartVoltage technology is a high-density, cost-effective, nonvolatile, read/write storage solution for a wide range of applications. It operates off of VDD = 2.7V and VPP = 2.7V. This low voltage operation capability realize battery life and suits for cellular phone application. Its Boot, Parameter and Main-blocked architecture, as well as low voltage and extended cycling. These features provide a highly flexible device suitable for portable terminals and personal computers. 

FEATURES
• SmartVoltage Technology
   − VDD = 2.7V, 3.3V or 5V
   − VPP = 2.7V, 3.3V, 5V or 12V
• User-Configurable x 8 or x 16 Operation
• High-Performance Access Time
   − 85 nS (5V ±0.25V), 90 nS (5V ±0.5V),
      100 nS (3.3V ±0.3V), 120 nS (2.7V to 3.6V)
• Operating Temperature
   − 0° C to +70° C
• Optimized Array Blocking Architecture
   − Two 4k-word (8k-byte) Boot Blocks
   − Six 4k-word (8k-byte) Parameter Blocks
   − Seven 32k-word (64k-byte) Main Blocks
   − Top Boot Location (W28V400TT)
   − Bottom Boot Location (W28V400BT)
• Extended Cycling Capability
   − Minimum 100,000 Block Erase Cycles
• Low Power Management
   − Deep Power-down Mode
   − Automatic Power Savings Mode Decreases
      ICCR in Static Mode
• Enhanced Automated Suspend Options
   − Word/Byte Write Suspend to Read
   − Block Erase Suspend to Word/Byte Write
   − Block Erase Suspend to Read
• Enhanced Data Protection Features
   − Absolute Protection with VPP ≤ VPPLK
   − Block Erase, Full Chip Erase, Word/Byte
      Write and Lock-Bit Configuration Lockout
      during Power Transitions
   − Block Blocks Protection with #WP = VIL
• Automated Word/Byte Write and Block Erase
   − Command User Interface (CUI)
   − Status Register (SR)
• SRAM-Compatible Write Interface
• Industry-Standard Packaging
   − 48-Lead TSOP