MT48LC64M4A2 Micron Technology, MT48LC64M4A2 Datasheet - Page 32

• Manufacturer Part Number: MT48LC64M4A2
• Description: (MT48Lxxxx) SYNCHRONOUS DRAM
• Manufacturer: Micron Technology

TRUTH TABLE 3 – CURRENT STATE BANK n, COMMAND TO BANK n
(Notes: 1-6; notes appear below and on next page)
NOTE: 1. This table applies when CKE
256Mb: x4, x8, x16 SDRAM
256MSDRAM_E.p65 – Rev. E; Pub. 3/02
CURRENT STATE CS# RAS# CAS# WE#
Row Active
Precharge
Precharge
Disabled)
Disabled)
(Auto
(Auto
Write
Read
Any
Idle
2. This table is bank-specific, except where noted, i.e., the current state is for a specific bank and the commands shown
3. Current state definitions:
4. The following states must not be interrupted by a command issued to the same bank. COMMAND INHIBIT or NOP
met (if the previous state was self refresh).
are those allowed to be issued to that bank when in that state. Exceptions are covered in the notes below.
commands, or allowable commands to the other bank should be issued on any clock edge occurring during these states.
Allowable commands to the other bank are determined by its current state and Truth Table 3, and according to Truth
Table 4.
Precharge Enabled: Starts with registration of a READ command with auto precharge enabled and ends when
Precharge Enabled: Starts with registration of a WRITE command with auto precharge enabled and ends when
Row Activating: Starts with registration of an ACTIVE command and ends when
Write w/Auto
Precharging: Starts with registration of a PRECHARGE command and ends when
Read w/Auto
H
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
Row Active: A row in the bank has been activated, and
Write: A WRITE burst has been initiated, with auto precharge disabled, and has not yet terminated
H
H
H
H
H
H
H
H
H
X
Read: A READ burst has been initiated, with auto precharge disabled, and has not yet terminated or
L
L
L
L
L
L
L
Idle: The bank has been precharged, and
X
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
register accesses are in progress.
been terminated.
or been terminated.
the bank will be in the idle state.
the bank will be in the row active state.
has been met. Once
has been met. Once
n-1
was HIGH and CKE
H
H
H
H
H
H
X
L
L
L
L
L
L
L
L
L
L
COMMAND (ACTION)
AUTO REFRESH
WRITE (Select column and start WRITE burst)
READ (Select column and start new READ burst)
BURST TERMINATE
READ (Select column and start READ burst)
PRECHARGE (Truncate WRITE burst, start PRECHARGE)
BURST TERMINATE
COMMAND INHIBIT (NOP/Continue previous operation)
NO OPERATION (NOP/Continue previous operation)
ACTIVE (Select and activate row)
LOAD MODE REGISTER
PRECHARGE
READ (Select column and start READ burst)
PRECHARGE (Deactivate row in bank or banks)
WRITE (Select column and start WRITE burst)
PRECHARGE (Truncate READ burst, start PRECHARGE)
WRITE (Select column and start new WRITE burst)
t
t
RP is met, the bank will be in the idle state.
RP is met, the bank will be in the idle state.
n
is HIGH (see Truth Table 2) and after
32
t
RP has been met.
t
RCD has been met. No data bursts/accesses and no
Micron Technology, Inc., reserves the right to change products or specifications without notice.
256Mb: x4, x8, x16
t
XSR has been
t
RCD is met. Once
t
RP is met. Once
©2002, Micron Technology, Inc.
SDRAM
t
RCD is met,
t
RP is met,
NOTES
10
10
10
10
10
10
11
t
7
7
8
8
9
8
9
RP
t
RP