mt47h64m16hw-3 Micron Semiconductor Products, mt47h64m16hw-3 Datasheet - Page 84

• Manufacturer Part Number: mt47h64m16hw-3
• Description: 1gb X4, X8, X16 Ddr2 Sdram
• Manufacturer: Micron Semiconductor Products

Figure 42:
Extended Mode Register 2 (EMR2)
Figure 43:
PDF: 09005aef8117c187/Source: 09005aef821aed36
DDR2_x4x8x16_Core2.fm - 1Gb DDR2: Rev. N; Core DDR2: Rev. C 4/08 EN
DQS, DQS#
Command
CK#
DQ
CK
ACTIVE n
T0
WRITE Latency
Extended Mode Register 2 (EMR2) Definition
Notes:
Notes:
WRITE n
1. BL = 4.
2. CL = 3.
3. WL = AL + CL - 1 = 4.
The extended mode register 2 (EMR2) controls functions beyond those controlled by the
mode register. Currently all bits in EMR2 are reserved, except for E7, which is used in
commercial or high-temperature operations, as shown in Figure 43. The EMR2 is
programmed via the LM command and will retain the stored information until it is
programmed again or until the device loses power. Reprogramming the EMR will not
alter the contents of the memory array, provided it is performed correctly.
Bit E7 (A7) must be programmed as “1” to provide a faster refresh rate on IT and AT
devices if T
EMR2 must be loaded when all banks are idle and no bursts are in progress, and the
controller must wait the specified time
tion. Violating either of these requirements could result in an unspecified operation.
1. E16 (BA2) is only applicable for densities >1Gb, reserved for future use, and must be pro-
2. Mode bits (En) with corresponding address balls (An) greater than E12 (A12) are reserved
T1
E15
0
0
1
1
grammed to “0.”
for future use and must be programmed to “0.”
E14
t RCD (MIN)
BA2
16
0
1
0
1
0
1
Extended mode register (EMR2)
Extended mode register (EMR3)
BA1
Extended mode register (EMR)
15
MRS
BA0
14
C
Mode register (MR)
Mode Register Set
AL = 2
exceeds 85°C.
NOP
0
An
n
T2
2
12
0
A12 A11
0
11
0
10
A10
WL = AL + CL - 1 = 4
0
9
A9
NOP
T3
0 SRT 0
8
A8
84
E7
0
1
7
A7 A6 A5 A4 A3
1X refresh rate (0°C to 85°C)
6
2X refresh rate (>85°C)
0
5
CL - 1 = 2
SRT Enable
Micron Technology, Inc., reserves the right to change products or specifications without notice.
t
0
4
MRD before initiating any subsequent opera-
NOP
T4
0
3
0
2
A2 A1 A0
0
1
1Gb: x4, x8, x16 DDR2 SDRAM
0
0
NOP
T5
DI
n
Extended mode
register (Ex)
Address bus
Transitioning Data
n + 1
DI
©2003 Micron Technology, Inc. All rights reserved.
NOP
n + 2
T6
DI
Operations
n + 3
DI
Don’t Care
NOP
T7