参数资料
型号: IS41LV44004-60J
英文描述: x4 EDO Page Mode DRAM
中文描述: x4 EDO公司页面模式的DRAM
文件页数: 3/19页
文件大小: 157K
代理商: IS41LV44004-60J
Integrated Silicon Solution, Inc.
1-800-379-4774
Rev. D
06/24/01
3
IS41C4400
X
IS41LV4400
X
S
ERIES
ISSI
Functional Description
The IS41C4400x and IS41LV4400x are CMOS
DRAMs optimized for high-speed bandwidth, low
power applications. During READ or WRITE cycles, each
bit is uniquely addressed through the 11 or 12 address
bits. These are entered 11 bits (A0-A10) at a time for the
2K refresh device or 12 bits (A0-A11) at a time for the 4K
refresh device. The row address is latched by the Row
Address Strobe (
RAS
). The column address is latched by
the Column Address Strobe (
CAS
).
RAS
is used to latch
the first nine bits and
CAS
is used the latter ten bits.
Memory Cycle
A memory cycle is initiated by bring
RAS
LOW and it is
terminated by returning both
RAS
and
CAS
HIGH. To
ensures proper device operation and data integrity any
memory cycle, once initiated, must not be ended or
aborted before the minimum t
RAS
time has expired. A new
cycle must not be initiated until the minimum precharge
time t
RP
, t
CP
has elapsed.
Read Cycle
A read cycle is initiated by the falling edge of
CAS
or
OE
,
whichever occurs last, while holding
WE
HIGH. The
column address must be held for a minimum time
specified by t
AR
. Data Out becomes valid only when t
RAC
,
t
AA
, t
CAC
and t
OEA
are all satisfied. As a result, the access
time is dependent on the timing relationships between
these parameters.
Write Cycle
A write cycle is initiated by the falling edge of
CAS
and
WE
, whichever occurs last. The input data must be valid
at or before the falling edge of
CAS
or
WE
, whichever
occurs last.
Auto Refresh Cycle
To retain data, 2,048 refresh cycles are required in each
32 ms period, or 4,096 refresh cycles are required in
each 64ms period. There are two ways to refresh the
memory:
1. By clocking each of the 2,048 row addresses (A0
through A10) or 4096 row addresses (A0 through
A11) with RAS at least once every 32 ms or 64ms
respectively. Any read, write, read-modify-write or
RAS-only cycle refreshes the addressed row.
2. Using a
CAS
-before-
RAS
refresh cycle.
CAS
-before-
RAS
refresh is activated by the falling edge of
RAS
, while
holding
CAS
LOW. In
CAS
-before-
RAS
refresh cycle,
an internal 9-bit counter provides the row addresses
and the external address inputs are ignored.
CAS
-before-
RAS
is a refresh-only mode and no data
access or device selection is allowed. Thus, the output
remains in the High-Z state during the cycle.
Power-On
After application of the V
CC
supply, an initial pause of 200
μs is required followed by a minimum of eight initialization
cycles (any combination of cycles containing a
RAS
signal).
During power-on, it is recommended that
RAS
track with
V
CC
or be held at a valid V
IH
to avoid current surges.
相关PDF资料
PDF描述
IS41LV44004-60JI x4 EDO Page Mode DRAM
IS41LV44004-60T x4 EDO Page Mode DRAM
IS41LV44004-60TI x4 EDO Page Mode DRAM
IS41LV44052-50J x4 Fast Page Mode DRAM
IS41LV44052-50JI x4 Fast Page Mode DRAM
相关代理商/技术参数
参数描述
IS41LV44004-60JI 制造商:未知厂家 制造商全称:未知厂家 功能描述:x4 EDO Page Mode DRAM
IS41LV44004-60T 制造商:未知厂家 制造商全称:未知厂家 功能描述:x4 EDO Page Mode DRAM
IS41LV44004-60TI 制造商:未知厂家 制造商全称:未知厂家 功能描述:x4 EDO Page Mode DRAM
IS41LV4400X 制造商:ISSI 制造商全称:Integrated Silicon Solution, Inc 功能描述:4M x 4 (16-MBIT) DYNAMIC RAM WITH EDO PAGE MODE
IS41LV44052 制造商:ISSI 制造商全称:Integrated Silicon Solution, Inc 功能描述:4M x 4 (16-MBIT) DYNAMIC RAM WITH FAST PAGE MODE