參數(shù)資料
型號: AT49BV040T-20TI
廠商: ATMEL CORP
元件分類: DRAM
英文描述: 4-Megabit 512K x 8 Single 2.7-volt Battery-Voltage Flash Memory
中文描述: 512K X 8 FLASH 2.7V PROM, 200 ns, PDSO32
封裝: 8 X 20 MM, PLASTIC, MO-142BD, TSOP-32
文件頁數(shù): 2/12頁
文件大?。?/td> 210K
代理商: AT49BV040T-20TI
AT49BV/LV040
2
Block Diagram
OE, CE, AND WE
LOGIC
Y DECODER
X DECODER
INPUT/OUTPUT
BUFFERS
DATA LATCH
Y-GATING
OPTIONAL BOOT
BLOCK (16K BYTES)
MAIN MEMORY
(496K BYTES)
OE
WE
CE
ADDRESS
INPUTS
V
CC
GND
DATA INPUTS/OUTPUTS
I/O7 - I/O0
8
03FFFH
00000H
INPUT/OUTPUT
BUFFERS
DATA LATCH
Y-GATING
OPTIONAL BOOT
BLOCK (16K BYTES)
MAIN MEMORY
(496K BYTES)
7C000H
00000H
AT49BV/LV040T
AT49BV/LV040
DATA INPUTS/OUTPUTS
I/O7 - I/O0
8
7FFFFH
7FFFFH
Device Operation
READ:
The AT49BV/LV040 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 con-
tention.
ERASURE:
Before a byte can be reprogrammed, the
512K bytes memory array (or 496K bytes if the boot block
featured is used) must be erased. The erased state of the
memory bits is a logical “1”. The entire device can be
erased at one time by using a 6-byte software code. The
software chip erase code consists of 6-byte load com-
mands to specific address locations with a specific data
pattern (please refer to the Chip Erase Cycle Waveforms).
After the software chip erase has been initiated, the device
will internally time the erase operation so that no external
clocks are required. The maximum time needed to erase
the whole chip is t
EC
. If the boot block lockout feature has
been enabled, the data in the boot sector will not be
erased.
BYTE PROGRAMMING:
Once the memory array is erased,
the device is programmed (to a logical “0”) on a byte-by-
byte basis. Please note that a data “0” cannot be pro-
grammed back to a “1”; only erase operations can convert
“0”s to “1”s. Programming is accomplished via the internal
device command register and is a 4 bus cycle operation
(please refer to the Command Definitions table). The
device will automatically generate the required internal pro-
gram pulses.
The program cycle has addresses latched on the falling
edge of WE or CE, whichever occurs last, and the data
latched on the rising edge of WE or CE, whichever occurs
first. Programming is completed after the specified t
BP
cycle time. The DATA polling feature may also be used to
indicate the end of a program cycle.
BOOT BLOCK PROGRAMMING LOCKOUT:
The device
has one designated block that has a programming lockout
feature. This feature prevents programming of data in the
designated block once the feature has been enabled. The
size of the block is 16K bytes. This block, referred to as the
boot block, can contain secure code that is used to bring up
the system. Enabling the lockout feature will allow the boot
code to stay in the device while data in the rest of the
device is updated. This feature does not have to be acti-
vated; the boot block's usage as a write protected region is
optional to the user. The address range of the
AT49BV/LV040 boot block is 00000H to 03FFFH while the
address range of the AT49BV/LV040T boot block is
7C000H to 7FFFFH.
To allow for simple in-system reprogrammability, the
AT49BV/LV040 does not require high input voltages for
programming. Three-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.
Reprogramming the AT49BV/LV040 is performed by eras-
ing the entire 4 megabits of memory and then programming
on a byte-by-byte basis. The typical byte programming
time is a fast 30
μ
s. The end of a program cycle can be
optionally detected by the DATA polling feature. Once the
end of a byte program cycle has been detected, a new
access for a read or program can begin. The typical num-
ber of program and erase cycles is in excess of 10,000
cycles.
The optional 16K bytes boot block section includes a repro-
gramming write 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 perma-
nently protected from being reprogrammed.
相關(guān)PDF資料
PDF描述
AT49BV040T-20VC LM4670 Boomer ® Audio Power Amplifier Series Filterless High Efficiency 3W Switching Audio Amplifier; Package: MICRO SMD; No of Pins: 9
AT49BV040T-20VI LM4670 Boomer ® Audio Power Amplifier Series Filterless High Efficiency 3W Switching Audio Amplifier; Package: MICRO SMD; No of Pins: 9
AT49LV040-70JC 4-megabit (512K x 8) Single 2.7-volt Battery-Voltage Flash Memory
AT49LV040-70JI LM4908 Boomer ® Audio Power Amplifier Series 10kV ESD Rated, Dual 120 mW Headphone Amplifier; Package: MINI SOIC; No of Pins: 8
AT49LV040-70TC 4-megabit (512K x 8) Single 2.7-volt Battery-Voltage Flash Memory
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AT49BV040T-20VC 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:4-Megabit 512K x 8 Single 2.7-volt Battery-Voltage Flash Memory
AT49BV040T-20VI 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:4-Megabit 512K x 8 Single 2.7-volt Battery-Voltage Flash Memory
AT49BV040T-90JC 制造商:未知廠家 制造商全稱:未知廠家 功能描述:x8 Flash EEPROM
AT49BV040T-90JI 制造商:未知廠家 制造商全稱:未知廠家 功能描述:x8 Flash EEPROM
AT49BV040T-90TC 制造商:未知廠家 制造商全稱:未知廠家 功能描述:x8 Flash EEPROM