AT49F8192-12RC ATMEL [ATMEL Corporation], AT49F8192-12RC Datasheet - Page 2

• Manufacturer Part Number: AT49F8192-12RC
• Description: 8-Megabit 512K x 16 5-volt Only CMOS Flash Memory
• Manufacturer: ATMEL [ATMEL Corporation]

The device contains a user-enabled “boot block” protection
feature. Two versions of the feature are available: the
AT49F8192 locates the boot block at lowest order
addresses (“bottom boot”); the AT49F8192T locates it at
highest order addresses (“top boot”).
To allow for simple in-system reprogrammability, the
AT49F8192 does not require high input voltages for pro-
gramming. Five-volt-only commands determine the read
and programming operation of the device. Reading data
out of the device is similar to reading from an EPROM; it
has standard CE, OE, and WE inputs to avoid bus conten-
tion. Reprogramming the AT49F8192 is performed by first
erasing a block of data and then programming on a word-
by-word basis.
The device is erased by executing the erase command
sequence; the device internally controls the erase opera-
Block Diagram
Device Operation
READ: The AT49F8192 is accessed like an EPROM.
When CE and OE are low and WE is high, the data stored
at the memory location determined by the address pins is
asserted on the outputs. The outputs are put in the high
impedance state whenever CE or OE is high. This dual-line
control gives designers flexibility in preventing bus conten-
tion.
COMMAND SEQUENCES: When the device is first pow-
ered on it will be reset to the read or standby mode
depending upon the state of the control line inputs. In order
to perform other device functions, a series of command
sequences are entered into the device. The command
sequences are shown in the Command Definitions table
(I/O8 - I/O15 are don't care inputs for the command codes).
The command sequences are written by applying a low
pulse on the WE or CE input with CE or WE low (respec-
tively) and OE high. The address is latched on the falling
2
AT49F8192/8192T
ADDRESS
INPUTS
RESET
GND
V
WE
OE
CE
CC
Y DECODER
X DECODER
CONTROL
LOGIC
DATA INPUTS/OUTPUTS
PROGRAM DATA
INPUT/OUTPUT
MAIN MEMORY
(488K WORDS)
PARAMETER
PARAMETER
BOOT BLOCK
I/O0 - I/O15
8K WORDS
8K WORDS
BUFFERS
LATCHES
Y-GATING
8K WORDS
BLOCK 2
BLOCK 1
AT49F8192
tion. The memory is divided into three blocks for erase
operations. There are two 8K word parameter block sec-
tions and one sector consisting of the boot block and the
main memory array block. The AT49F8192 is programmed
on a word-by-word basis. The device has the capability to
protect the data in the boot block; this feature is enabled by
a command sequence. Once the boot block programming
lockout feature is enabled, the data in the boot block can-
not be changed when input levels of 5.5 volts or less are
used. The typical number of program and erase cycles is in
excess of 10,000 cycles.
The optional 8K word boot block section includes a repro-
gramming 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 permanently
protected from being reprogrammed.
edge of CE or WE, whichever occurs last. The data is
latched by the first rising edge of CE or WE. Standard
microprocessor write timings are used. The address loca-
tions used in the command sequences are not affected by
entering the command sequences.
RESET: A RESET input pin is provided to ease some sys-
tem applications. When RESET is at a logic high level, the
device is in its standard operating mode. A low level on the
RESET input halts the present device operation and puts
the outputs of the device in a high impedance state. When
a high level is reasserted on the RESET pin, the device
returns to the Read or Standby mode, depending upon the
state of the control inputs. By applying a 12V
signal to the RESET pin the boot block array can be repro-
grammed even if the boot block program lockout feature
has been enabled (see Boot Block Programming Lockout
Override section).
7FFFF
05FFF
03FFF
01FFF
00000
06000
04000
02000
DATA INPUTS/OUTPUTS
PROGRAM DATA
INPUT/OUTPUT
MAIN MEMORY
(488K WORDS)
BOOT BLOCK
PARAMETER
PARAMETER
I/O0 - I/O15
8K WORDS
8K WORDS
8K WORDS
BUFFERS
LATCHES
Y-GATING
BLOCK 1
BLOCK 2
AT49F8192T
7FFFF
7DFFF
7BFFF
7E000
7C000
7A000
79FFF
00000
0.5V input