4 Megabit

(512K x 8)

3-volt Only

256 Byte Sector

CMOS Flash

Memory

Features

15 mA Active Current

20

µA CMOS Standby Current

Single Cycle Reprogram (Erase and Program)

2048 Sectors (256 bytes/sector)

Internal Address and Data Latches for 256-Bytes

Description

The AT29LV040A is a 3-volt-only in-system Flash Programmable and Erasable Read

Only Memory (PEROM). Its 4 megabits of memory is organized as 524,288 words by

8 bits. Manufactured with Atmel’s advanced nonvolatile CMOS EEPROM technology,

the device offers access times up to 200 ns, and a low 54 mW power dissipation.

When the device is deselected, the CMOS standby current is less than 20

µA. The

device endurance is such that any sector can typically be written to in excess of

10,000 times. The programming algorithm is compatible with other devices in Atmel’s

3-volt-only Flash memories.

To allow for simple in-system reprogrammability, the AT29LV040A does not require

high input voltages for programming. Three-volt-only commands determine the opera-

tion of the device. Reading data out of the device is similar to reading from an EPROM.

Reprogramming the AT29LV040A 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 are captured

at microprocessor speed and internally latched, freeing the address and data bus for

other operations. Following the initiation of a program cycle, the device will automat-

ically erase the sector and then program the latched data using an internal control

timer. The end of a program cycle 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.

AT29LV040A

Pin Configurations

Pin Name

Function

A0 - A18

Addresses

CE

Chip Enable

OE

Output Enable

WE

Write Enable

I/O0 - I/O7

Data Inputs/Outputs

NC

No Connect

TSOP Top View

Type 1

0334C

AT29LV040A

4-83