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AS4SD4M16DG-10/XT 参数 Datasheet PDF下载

AS4SD4M16DG-10/XT图片预览
型号: AS4SD4M16DG-10/XT
PDF下载: 下载PDF文件 查看货源
内容描述: 4梅格×16 SDRAM同步动态随机存取存储 [4 Meg x 16 SDRAM Synchronous DRAM Memory]
分类和应用: 存储内存集成电路光电二极管动态存储器时钟
文件页数/大小: 50 页 / 1139 K
品牌: AUSTIN [ AUSTIN SEMICONDUCTOR ]
 浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第16页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第17页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第18页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第19页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第21页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第22页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第23页浏览型号AS4SD4M16DG-10/XT的Datasheet PDF文件第24页  
SDRAM  
AS4SD4M16  
Austin Semiconductor, Inc.  
Data for any WRITE burst may be truncated with a WRITE burst, the DQM signal must be used to mask input data  
subsequent READ command, and data for a fixed-length WRITE for the clock edge prior to, and the clock edge coincident with,  
burst may be immediately followed by a subsequent READ the PRECHARGE command. An example is shown in Figure 18.  
command. Once the READ command is registered, the data Data n + 1 is either the last of a burst of two or the last desired  
inputs will be ignored, and WRITEs will not be executed. An of a longer burst. Following the PRECHARGE command, a  
example is shown in Figure 17. Data n+1 is either the last of a subsequent command to the same bank cannot be issued until  
burst of two or the last desired of a longer burst.  
tRP is met.  
In the case of a fixed-length burst being executed to  
Data for a fixed-length WRITE burst may be followed  
by, or truncated with, a PRECHARGE command to the same  
bank (provided that AUTO PRECHARGE was not activated),  
and a full-page WRITE burst may be truncated with a  
PRECHARGE command to the same bank. The PRECHARGE  
completion, a PRECHARGE command issued at the optimum  
time (as described above) provides the same operation that  
would result from the same fixed-length burst with AUTO  
PRECHARGE. The disadvantage of the PRECHARGE command  
is that it requires that the command and address buses be  
available at the appropriate time to issue the command; the  
advantage of the PRECHARGE command is that it can be used  
t
command should be issued WR after the clock edge at which  
the last desired input data element is registered. The Auto  
Precharge mode requires a tWR of at least one clock plus time  
(8ns), regardless of frequency. In addition, when truncating a to truncate fixed-length or full-page bursts.  
T0  
T1  
T2  
T3  
T0  
T1  
T2  
T3  
T4  
T5  
T6  
CLK  
CLK  
tWR= 2 CLK (“A2 version”)  
WRITE  
WRITE  
WRITE  
COMMAND  
WRITE  
DQM  
t
RP  
BANK,  
COL n  
BANK,  
COL m  
BANK,  
COL a  
BANK,  
COL x  
ADDRESS  
DQ  
NOP  
PRECHARGE  
NOP  
NOP  
ACTIVE  
NOP  
WRITE  
COMMAND  
DIN  
n
DIN a  
DIN  
x
DIN m  
BANK  
a,  
COL n  
BANK  
(a or all)  
BANK  
a,  
ROW  
ADDRESS  
DQ  
t
WR  
NOTE: Each WRITE command may be to any bank. DQM is  
DIN  
n
DIN n+1  
LOW.  
Figure 16  
NOTE: DQM coulc remain LOW in this example if the WRITE burst is a fixed length  
RANDOM WRITE CYCLES  
of 2.  
DON’T CARE  
Figure 18  
WRITE TO PRECHARGE  
T0  
T1  
T2  
T3  
T4  
T5  
CLK  
COMMAND  
WRITE  
NOP  
NOP  
READ  
NOP  
NOP  
BANK,  
COL n  
BANK,  
COL b  
ADDRESS  
DQ  
DOUT  
b
DOUT b+1  
DIN  
n
DIN n+1  
NOTE: The WRITE command may be to any bank, and the READ command may be to  
any bank. DQM is LOW. CAS latency = 2 for illustration.  
Figure 17  
WRITE TO READ  
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.  
AS4SD4M16  
Rev. 1.5 10/01  
20  
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