CAS2/150MHz HSDRAM
64MB, 128MB DIMM
Preliminary Data Sheet
Features
Pin
Symbol
Pin
Symbol
Pin
Symbol
Pin
Symbol
•
•
JEDEC PC-133 SDRAM DIMM Compatible
CAS 2 150MHz Modules (2:3:2) @ 150 MHz
1
Vss
DQ0
DQ1
DQ2
DQ3
Vdd
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
Vss
DNU
S2#
85
86
Vss
DQ32
DQ33
DQ34
DQ35
Vdd
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
Vss
CKE0
S3#
2
•
•
•
CAS Latency = 2
RAS to CAS Delay = 3
Precharge Delay = 2
3
87
4
DQMB2
DQMB3
DNU
Vdd
88
DQMB6
DQMB7
RFU
Vdd
5
89
•
•
•
•
•
•
•
•
•
Fast 4.5 ns Clock Access Time
6
90
Overclock Existing PC Systems to 150 MHz +
Ideal for Low Cost 150 MHz Bus Speed Systems
Supports CAS Latency = 2, 3
On-board Serial Presence Detect (SPD)
Unbuffered 168-pin DIMM
7
DQ4
DQ5
DQ6
DQ7
DQ8
Vss
91
DQ36
DQ37
DQ38
DQ39
DQ40
Vss
8
NC
92
NC
9
NC
93
NC
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
CB2
94
CB6
4K Refresh / 64 ms
CB3
95
CB7
Single 3.3V ± 0.3V Power Supply
Available on-line at http://www.pc133memory.com or
http://www.mushkin.com
Vss
96
Vss
DQ9
DQ10
DQ11
DQ12
DQ13
Vdd
DQ16
DQ17
DQ18
DQ19
Vdd
97
DQ41
DQ42
DQ43
DQ44
DQ45
Vdd
DQ48
DQ49
DQ50
DQ51
Vdd
98
99
Description
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
The Enhanced Memory Systems 64MB and 128MB CAS 2
150MHz HSDRAM DIMMs are the fastest unbuffered
SDRAM DIMMs available. Low latency (2:3:2) at 150 MHz
improves performance in high-end desktop publishing and
graphics applications, particularly with UMA system
architectures. The fast 4.5 ns clock access time allows
unbuffered DIMM operation at 150 MHz for lower memory
latency, and lower costs than registered DIMMs.
DQ20
NC
DQ52
NC
DQ14
DQ15
CB0
CB1
Vss
DQ46
DQ47
CB4
NC
NC
CKE1
Vss
NC
CB5
Vss
DQ21
DQ22
DQ23
Vss
Vss
DQ53
DQ54
DQ55
Vss
The 64MB module (SM6408DT-6.6) is organized as 8Mx64,
and the 128MB module (SM12808DT-6.6) is organized as
16Mx64. The 128MB ECC module (SM12809DT-6.6) is
organized as 16Mx72. Each module contains a serial
presence EEPROM programmed by Enhanced Memory
Systems, which contains information on the module type,
module organization, component speed, and other attributes
relevant to the system controller.
NC
NC
NC
NC
Vdd
Vdd
WE#
DQMB0
DQMB1
S0#
DQ24
DQ25
DQ26
DQ27
Vdd
CAS#
DQMB4
DQMB5
S1#
DQ56
DQ57
DQ58
DQ59
Vdd
DNU
Vss
RAS#
Vss
DQ28
DQ29
DQ30
DQ31
Vss
DQ60
DQ61
DQ62
DQ63
Vss
A0
A1
A2
A3
A4
A5
A6
A7
A8
CK2
A9
CK3
A10/AP
BA1
Vdd
NC
BA0
NC
WP
A11
SA0
SDA
SCL
Vdd
SA1
Vdd
CK1
SA2
CK0
Vdd
RFU
Vdd
Enhanced Memory Systems Inc., 1850 Ramtron Dr., Colo Spgs, CO 80921
PHONE: (800) 545-DRAM; FAX: (719) 488-9095; http://www.edram.com
2000 Enhanced Memory Systems. All rights reserved.
The information contained herein is subject to change without notice.
Revision 1.0
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