mt47h128m16hg-3-it Micron Semiconductor Products, mt47h128m16hg-3-it Datasheet - Page 16

• Manufacturer Part Number: mt47h128m16hg-3-it
• Description: 2gb X4, X8, X16 Ddr2 Sdram
• Manufacturer: Micron Semiconductor Products

State Diagram
Figure 7:
PDF: 09005aef824f87b6/Source: 09005aef824f1182
2gb_ddr2.fm - Rev. A 9/06 EN
Simplified State Diagram
calibration
Setting
EMRS
MRS
OCD
WRITE
Precharge
Writing
Writing
(E)MRS
WR_A
Auto
with
Figure 7 shows a simplified state diagram to provide the basic command flow. It is not
comprehensive and does not identify all timing requirements or possible command
restrictions.
Power-
Active
Down
Automatic Sequence
Command Sequence
WR_A
PRE
Initialization
Precharged
Precharging
Sequence
PRE, PRE_A
All banks
Activating
Active
Bank
Idle
ACT
16
READ
ACT = Activate
CKE_H = CKE HIGH, exit power-down or self refresh
CKE_L = CKE LOW, enter power-down
(E)MRS = (Extended) mode register set
PRE = PRECHARGE
PRE_A = PRECHARGE ALL
READ = READ
RD_A = READ with auto precharge
REFRESH = REFRESH
SR = SELF REFRESH
WRITE = WRITE
WR_A = WRITE with auto precharge
Micron Technology, Inc., reserves the right to change products or specifications without notice.
Precharge
Power-
Down
Precharge
Reading
Reading
RD_A
with
Auto
REFRESH
Refreshing
2Gb: x4, x8, x16 DDR2 SDRAM
CKE_L
Self
READ
CKE_L
Refreshing
©2006 Micron Technology, Inc. All rights reserved.
State Diagram