AT49F002ANT

Temperature Under Bias................................ -55 to +125
Storage Temperature ....................................-65 to +150
All Input Voltages
(including NC Pins)
with Respect to Ground ................................-0.6V to +6.25V
All Output Voltages
with Respect to Ground ..........................-0.6V to V_CC + 0.6V
Voltage on OE
with Respect to Ground ..................................-0.6V to +13.5V
*NOTICE: Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

The AT49F002A(N)(T) is a 5-volt only in-system reprogrammable Flash memory. Its 2 megabits of memory is organized as 262,144 words by 8 bits. Manufactured with Atmel's advanced nonvolatile CMOS technology, the device offers access times to 55 ns with power dissipation of just 137 mW over the industrial temperature range.When AT49F002AN is deselected, the CMOS standby current is less than 100 A. For the AT49F002AN(T) pin 1 for the PLCC package and pin 9 for the TSOP package are no connect pins.

To allow for simple in-system reprogrammability, the AT49F002A(N)(T) 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 AT49F002AN is similar to reading from an EPROM; AT49F002AN has standard CE, OE, and WE inputs to avoid bus contention. Reprogramming the AT49F002A(N)(T) is performed by erasing a block of data and then programming on a byte-by-byte basis. The byte programming time is a fast 20 s. The end of a program cycle can be optionally detected by the DATA polling feature. Once the end of a byte program cycle of AT49F002AN has been detected, a new access for a read or program can begin. The typical number of program and erase cycles is in excess of 10,000 cycles.

AT49F002AN is erased by executing the erase command sequence; the device internally controls the erase operations. There are two 8K byte parameter block sections,four main memory blocks, and one boot block.

AT49F002AN has the capability to protect the data in the boot block; this feature is enabled by a command sequence. The 16K-byte boot block section includes a reprogramming lock out feature to provide data integrity. The boot sector is designed to contain user secure code, and when the feature is enabled, the boot sector is protected from being reprogrammed.

In the AT49F002A(N)(T), once the boot block programming lockout feature is enabled, the con-tents of the boot block are permanent and cannot be changed. In the AT49F002A(T), once the boot block programming lockout feature ofAT49F002AN is enabled, the contents of the boot block cannot be changed with input voltage levels of 5.5 volts or less.