DESCRIPTION
The Microchip Technology Inc. 27C256 is a CMOS 256K bit electrically Programmable Read Only Memory (EPROM). The device is organized as 32K words by 8 bits (32K bytes). Accessing individual bytes from an address transition or from power-up (chip enable pin going low) is accomplished in less than 90 ns. This very high speed device allows the most sophisticated microprocessors to run at full speed without the need for WAIT states. CMOS design and processing enables this part to be used in systems where reduced power consumption and reliability are requirements.

FEATURES
• High speed performance
   - 90 ns access time available
• CMOS Technology for low power consumption
   - 20 mA Active current
   - 100 µA Standby current
• Factory programming available
• Auto-insertion-compatible plastic packages
• Auto ID aids automated programming
• Separate chip enable and output enable controls
• High speed “express” programming algorithm
• Organized 32K x 8: JEDEC standard pinouts
   - 28-pin Dual-in-line package
   - 32-pin PLCC Package
   - 28-pin SOIC package
   - 28-pin Thin Small Outline Package (TSOP)
   - 28-pin Very Small Outline Package (VSOP)
   - Tape and reel
• Data Retention > 200 years
• Available for the following temperature ranges:
   - Commercial: 0˚C to +70˚C
   - Industrial: -40˚C to +85˚C
   - Automotive: -40˚C to +125˚C