GENERAL DESCRIPTION
The MT28F004B5 (x8) and MT28F400B5 (x16, x8) are nonvolatile, electrically block-erasable (flash), programmable, read-only memories containing 4,194,304 bits organized as 262,144 words (16 bits) or 524,288 bytes (8 bits). Writing or erasing the device is done with a 5V VPP voltage, while all operations are performed with a 5V VCC. Due to process technology advances, 5V VPP is optimal for application and production programming. For backward compatibility with SmartVoltage technology, 12V VPP is supported for a maximum of 100 cycles and may be connected for up to 100 cumulative hours. These devices are fabricated with Micron’s advanced CMOS floating-gate process.

FEATURES
• Seven erase blocks:
   16KB/8K-word boot block (protected)
   Two 8KB/4K-word parameter blocks
   Four main memory blocks
• Smart 5 technology (B5):
   5V ±10% VCC
   5V ±10% VPP application/production
      programming
   12V ±5% VPP compatibility production
      programming
• Address access times: 60ns, 80ns
• 100,000 ERASE cycles
• Industry-standard pinouts
• Inputs and outputs are fully TTL-compatible
• Automated write and erase algorithm
• Two-cycle WRITE/ERASE sequence
• Byte- or word-wide READ and WRITE
   (MT28F400B5, 256K x 16/512K x 8)
• Byte-wide READ and WRITE only
   (MT28F004B5, 512K x 8)
• TSOP and SOP packaging options