AT29C020

Features:

` Fast Read Access Time - 90 ns
` 5-Volt-Only Reprogramming
` Sector Program Operation
    Single Cycle Reprogram (Erase and Program)
    1024 Sectors (256 bytes/sector)
    Internal Address and Data Latches for 256-Bytes
` Internal Program Control and Timer
` Hardware and Software Data Protection
` Two 8 KB Boot Blocks with Lockout
` Fast Sector Program Cycle Time - 10 ms
` DATA Polling for End of Program Detection
` Low Power Dissipation
    40 mA Active Current
    100 A CMOS Standby Current
` Typical Endurance > 10,000 Cycles
` Single 5V ±10% Supply
` CMOS and TTL Compatible Inputs and Outputs
` Commercial and Industrial Temperature Ranges


Pinout




Specifications

Temperature Under Bias................. -55°C to +125°C
Storage Temperature...................... -65°C to +150°C
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 VCC + 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.


Description

The AT29C020 is a 5-volt-only in-system Flash programmable and erasable read only memory (PEROM). Its 2 megabits of memory is organized as 262,144 bytes. Manufactured with Atmel's advanced nonvolatile CMOS technology, AT29C020 offers access times to 90 ns with power dissipation of just 220 mW over the commercial temperature range. When the device is deselected, the CMOS standby current is less than 100 mA. Device endurance is such that any sector can typically be written to in excess of 10,000 times.

To allow for simple in-system reprogrammability, the AT29C020 does not require high input voltages for programming. Five-volt-only commands determine the operation of the device. Reading data out of the device is similar to reading from an EPROM. Reprogramming the AT29C020 is performed on a sector basis; 256-bytes of data are loaded into the device and then simultaneously programmed.

During a reprogram cycle, the address locations and 256- bytes of data of AT29C020 are internally latched, freeing the address and data bus for other operations. Following the initiation of a program cycle, the device will automatically erase the sector and then program the latched data using an internal control timer. The end of a program cycle of AT29C020 can be detected by DATA polling of I/O7. Once the end of a program cycle has been detected, a new access for a read or program can begin.