mt48h8m16lf Micron Semiconductor Products, mt48h8m16lf Datasheet - Page 32

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

Table 18:
Initialization
PDF: 09005aef832ff1ea / Source: 09005aef832ff1ac
sdr_mobile_sdram_cmd_op_timing_dia_fr5.08__4.fm - Rev. B 6/08 EN
CKE
H
H
L
L
n-1
CKE
H
H
Truth Table – CKE
Notes 1–4; notes appear below this table
L
L
n
Notes:
Reading or writing
Deep power-down
Deep power-down
Current State
Clock suspend
Clock suspend
All banks idle
All banks idle
All banks idle
Power-down
Power-down
Self refresh
Self refresh
1. CKE
2. Current state is the state of the SDRAM immediately prior to clock edge n.
3. COMMAND
4. All states and sequences not shown are illegal or reserved.
5. Exiting power-down at clock edge n will put the device in the all banks idle state in time for
6. Exiting self refresh at clock edge n will put the device in the all banks idle state after
7. After exiting clock suspend at clock edge n, the device will resume operation and recognize
8. Deep power-down is a power savings feature of this Mobile SDRAM device. This command
Low-power SDRAMs must be powered up and initialized in a predefined manner. Oper-
ational procedures other than those specified may result in undefined operation. After
the power is applied to V
clock is defined as a signal cycling within timing constraints specified for the clock ball),
the SDRAM requires a 100µs delay prior to issuing any command other than a
COMMAND INHIBIT or NOP. Starting at some point during this 100µs period and
continuing at least through the end of this period, COMMAND INHIBIT or NOP
commands should be applied.
After the 100µs delay is satisfied by applying at least one COMMAND INHIBIT or NOP
command, a PRECHARGE command must be applied. All banks must then be
precharged, which places the device in the all banks idle state.
clock edge.
of COMMAND
clock edge n + 1 (provided that
met. COMMAND INHIBIT or NOP commands should be issued on any clock edges occurring
during the
t
the next command at clock edge n + 1.
is BURST TERMINATE when CKE is HIGH and DEEP POWER-DOWN when CKE is LOW.
XSR period.
n
is the logic state of CKE at clock edge n; CKE
t
n
XSR period. A minimum of two NOP commands must be provided during the
is the command registered at clock edge n, and ACTION
n
.
COMMAND INHIBIT or NOP
COMMAND INHIBIT or NOP
COMMAND INHIBIT or NOP
Table 17 on page 30
BURST TERMINATE
AUTO REFRESH
DD
Command
128Mb: 8 Meg x 16, 4 Meg x 32 Mobile SDRAM
and V
VALID
32
X
X
X
X
X
X
t
CKS is met).
DD
n
Q (simultaneously) and the clock is stable (stable
Micron Technology, Inc., reserves the right to change products or specifications without notice.
n-1
Maintain deep power-down
Deep power-down entry
was the state of CKE at the previous
Maintain clock suspend
Exit deep power-down
Maintain power-down
Maintain self refresh
Clock suspend entry
Power-down entry
Exit clock suspend
Exit power-down
Self refresh entry
Exit self refresh
Action
©2008 Micron Technology, Inc. All rights reserved.
n
n
is a result
Initialization
Preliminary
Notes
t
XSR is
5
6
7
8