Description
The AT49F040 is a 5-volt-only in-system Flash Memory. Its 4 megabits of memory is organized as 524,288 words by 8 bits. Manufactured with Atmel’s advanced nonvola tile CMOS technology, the device offers access times to 70 ns with power dissipation of just 275 mW over the commercial temperature range. When the device is dese lected, the CMOS standby current is less than 100 µA.
The device contains a user-enabled “boot block” protection feature. Two versions of the feature are available: the AT49F040 locates the boot block at lowest order addresses (“bottom boot”); the AT49F040T locates it at highest order addresses (“top boot”).
To allow for simple in-system reprogrammability, the AT49F040 does not require high input voltages for programming. Five-volt-only commands determine the read and programming operation of the device. Reading data out of the device is similar to reading from an EPROM.

FEATUREs
• Single Voltage Operation
   – 5V Read
   – 5V Reprogramming
• Fast Read Access Time - 70 ns
• Internal Program Control and Timer
• 16K bytes Boot Block With Lockout
• Fast Erase Cycle Time - 10 seconds
• Byte By Byte Programming - 50 µs/Byte
• Hardware Data Protection
• DATA Polling For End Of Program Detection
• Low Power Dissipation
   – 50 mA Active Current
   – 100 µA CMOS Standby Current
• Typical 10,000 Write Cycles