MT48H8M32LF Datasheet, PDF (34/71 Pages) Micron Technology – 256Mb: 16 Meg x 16, 8 Meg x 32 Mobile SDRAM

256Mb: 16 Meg x 16, 8 Meg x 32 Mobile SDRAM
Operations
Fixed-length or WRITE bursts can be truncated with the BURST TERMINATE command.
When truncating a WRITE burst, the input data applied coincident with the BURST
TERMINATE command will be ignored. The last data written (provided that DQM is
LOW at that time) will be the input data applied one clock previous to the BURST
TERMINATE command. This is shown in Figure 22 on page 32, where data n is the last
desired data element of a longer burst.
PRECHARGE
The PRECHARGE command (see Figure 25) is used to deactivate the open row in a
particular bank or the open row in all banks. The bank(s) will be available for a subse-
quent row access some specified time (^tRP) after the precharge command is issued.
Input A10 determines whether one or all banks are to be precharged, and in the case
where only one bank is to be precharged, inputs BA0, BA1 select the bank. When all
banks are to be precharged, inputs BA0, BA1 are treated as “Don’t Care.” Once a bank has
been precharged, it is in the idle state and must be activated prior to any READ or WRITE
commands being issued to that bank.
Figure 25: PRECHARGE Command
CLK
CKE HIGH
CS#
RAS#
CAS#
WE#
Power-Down
A0–A9, A11, A12
A10
BA0, BA1
All Banks
Bank Selected
BANK
ADDRESS
VALID ADDRESS
DON’T CARE
Power-down occurs if CKE is registered LOW coincident with a NOP or COMMAND
INHIBIT when no accesses are in progress. If power-down occurs when all banks are
idle, this mode is referred to as precharge power-down; if power-down occurs when
there is a row active in any bank, this mode is referred to as active power-down. Entering
power-down deactivates the input and output buffers, excluding CKE, for maximum
power savings while in standby. The device may not remain in the power-down state
longer than the refresh period (64ms) since no REFRESH operations are performed in
this mode.
PDF:09005aef8219eeeb/Source: 09005aef8219eedd
MT48H16M16LF_2.fm - Rev F 4/07 EN
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