mt48h8m16lf Micron Semiconductor Products, mt48h8m16lf Datasheet - Page 50

• Manufacturer Part Number: mt48h8m16lf
• Description: 128mb 8 Meg X 16, 4 Meg X 32 Mobile Sdram
• Manufacturer: Micron Semiconductor Products

Figure 27:
PDF: 09005aef832ff1ea / Source: 09005aef832ff1ac
sdr_mobile_sdram_cmd_op_timing_dia_fr5.08__4.fm - Rev. B 6/08 EN
WRITE-to-WRITE
Notes:
1. DQM is LOW. Each WRITE command may be to any bank.
Data for any WRITE burst may be truncated with a subsequent READ command, and
data for a fixed-length WRITE burst may be immediately followed by a READ command.
After the READ command is registered, the data inputs is ignored, and WRITEs will not
be executed. An example is shown in Figure 29 on page 51. Data n + 1 is either the last of
a burst of two or the last desired of a longer burst.
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 acti-
vated) and a continuous-page WRITE burst may be truncated with a PRECHARGE
command to the same bank. The PRECHARGE command should be issued
clock edge at which the last desired input data element is registered. The auto precharge
mode requires a
In addition, when truncating a WRITE burst at high clock frequencies (
DQM signal must be used to mask input data for the clock edge prior to, and the clock
edge coincident with, the PRECHARGE command. An example is shown in Figure 30 on
page 52. Data n + 1 is either the last of a burst of two or the last desired of a longer burst.
Following the PRECHARGE command, a subsequent command to the same bank
cannot be issued until
In the case of a fixed-length burst being executed to 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 disadvan-
tage 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 to truncate fixed-length bursts or
continuous page bursts.
Command
Address
CLK
DQ
WRITE
Bank,
Col n
D
T0
n
IN
t
WR of at least one clock plus time, regardless of frequency.
n + 1
NOP
T1
D
t
IN
RP is met.
Don’t Care
128Mb: 8 Meg x 16, 4 Meg x 32 Mobile SDRAM
50
WRITE
Bank,
Col b
T2
D
b
IN
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2008 Micron Technology, Inc. All rights reserved.
Timing Diagrams
t
CK < 15ns), the
t
WR after the
Preliminary