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Features
• 2.7V to 3.6V Read/Write Operation
• Fast Read Access Time - 120 ns
• Internal Erase/Program Control
• Sector Architecture
– One 8K Words (16K bytes) Boot Block with Programming Lockout
– Two 4K Words (8K bytes) Parameter Blocks
– One 240K Words (480K bytes) Main Memory Array Block
• Fast Sector Erase Time - 10 seconds
• Byte-by-Byte or Word-By-Word Programming - 30 µs Typical
• Hardware Data Protection
• DATA Polling For End Of Program Detection
• Low-Power Dissipation
– 25 mA Active Current
–50 µA CMOS Standby Current
• Typical 10,000 Write Cycles
Description
The AT49BV004(T) and AT49BV4096A(T) are 3-volt, 4-megabit Flash Memories
organized as 524,288 words of 8 bits each or 256K words of 16 bits each. Manufac-
tured with Atmel’s advanced nonvolatile CMOS technology, the devices offer access
times to 120 ns with power dissipation of just 67 mW at 2.7V read. When deselected,
the CMOS standby current is less than 50 µA.
The device contains a user-enabled “boot block” protection feature. Two versions of
the feature are available: the AT49BV004/4096A locates the boot block at lowest
order addresses (“bottom boot”); the AT49BV004T/4096AT locates it at highest order
addresses (“top boot”).
To allow for simple in-system reprogrammability, the AT49BV004(T)/4096A(T) does
not require high input voltages for programming. Reading data out of the device is
similar to reading from an EPROM; it has standard CE, OE, and WE inputs to avoid
bus contention. Reprogramming the AT49BV004(T)/4096A(T) is performed by first
erasing a block of data and then programming on a byte-by-byte or word-by-word
basis.
4-Megabit
(512K x 8/
256K x 16)
CMOS Flash
Memory
AT49BV004
AT49BV004T
AT49BV4096A
AT49BV4096AT
Preliminary
Rev. 1139A–09/98
Pin Configurations
Pin Name Function
A0 - A18 Addresses
CE Chip Enable
OE Output Enable
WE Write Enable
RESET Reset
RDY/BUSY Ready/Busy Output
VPP
Optional Power Supply for Faster
Program/Erase Operations
I/O0 - I/O14 Data Inputs/Outputs
I/O15(A-1)
I/O15 (Data Input/Output, Word Mode)
A-1 (LSB Address Input, Byte Mode)
BYTE Selects Byte or Word Mode
NC No Connect
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