
4 Megabit
(512K x 8)
Single 2.7-volt
Battery-Voltage
CMOS Flash
Memory
Preliminary
Features
Single Supply Voltage, Range 2.7V to 3.6V
Single Supply for Read and Write
Software Protected Programming
Fast Read Access Time - 250 ns
Low Power Dissipation
15 mA Active Current
20
μ
A CMOS Standby Current
Sector Program Operation
Single Cycle Reprogram (Erase and Program)
2048 Sectors (256 bytes/sector)
Internal Address and Data Latches for 256-Bytes
Two 16 KB Boot Blocks with Lockout
Fast Sector Program Cycle Time - 20 ms Max.
Internal Program Control and Timer
DATA Polling for End of Program Detection
Typical Endurance > 10,000 Cycles
CMOS and TTL Compatible Inputs and Outputs
Commercial and Industrial Temperature Ranges
Description
The AT29BV040A 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 250 ns, and a low 54 mW power dissipation.
When the device is deselected, the CMOS standby current is less than 20
μ
A. 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
2.7-volt-only Flash memories.
To allow for simple in-system reprogrammability, the AT29BV040A does not require
high input voltages for programming. The device can be operated with a single 2.7V
to 3.6V supply. Reading data out of the device is similar to reading from an EPROM.
Reprogramming the AT29BV040A 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.
AT29BV040A
TSOP Top View
Type 1
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
0383B
AT29BV040A
4-23