Preliminary Data Sheet
PC-133 HSDRAM
256MB, 512MB DIMM
Features
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JEDEC Standard PC-133 SDRAM DIMM
Highest Density PC-133 SDRAM Unbuffered DIMMs
256 Mbit HSDRAM Chip Components
Fast 4.6 ns Clock Access Time
Ideal for High Performance 133 MHz Bus Speed
Workstations and Servers
On-board Serial Presence Detect (SPD)
Unbuffered 168-pin DIMM
8K Refresh / 64 ms
Single 3.3V
±
0.3V Power Supply
Available on-line at
http://www.pc133memory.com
Pin
1
2
3
4
5
6
7
8
9
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
Symbol
Vss
DQ0
DQ1
DQ2
DQ3
Vdd
DQ4
DQ5
DQ6
DQ7
DQ8
Vss
DQ9
DQ10
DQ11
DQ12
DQ13
Vdd
DQ14
DQ15
CB0
CB1
Vss
NC
NC
Vdd
WE#
DQMB0
DQMB1
S0#
DU
Vss
A0
A2
A4
A6
A8
A10/AP
BA1
Vdd
Vdd
CK0
Pin
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
Symbol
Vss
DU
S2#
DQMB2
DQMB3
DU
Vdd
NC
NC
CB2
CB3
Vss
DQ16
DQ17
DQ18
DQ19
Vdd
DQ20
NC
NC
CKE1
Vss
DQ21
DQ22
DQ23
Vss
DQ24
DQ25
DQ26
DQ27
Vdd
DQ28
DQ29
DQ30
DQ31
Vss
CK2
NC
WP
SDA
SCL
Vdd
Pin
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
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
Symbol
Vss
DQ32
DQ33
DQ34
DQ35
Vdd
DQ36
DQ37
DQ38
DQ39
DQ40
Vss
DQ41
DQ42
DQ43
DQ44
DQ45
Vdd
DQ46
DQ47
CB4
CB5
Vss
NC
NC
Vdd
CAS#
DQMB4
DQMB5
S1#
RAS#
Vss
A1
A3
A5
A7
A9
BA0
A11
Vdd
CK1
A12
Pin
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
Symbol
Vss
CKE0
S3#
DQMB6
DQMB7
RFU
Vdd
NC
NC
CB6
CB7
Vss
DQ48
DQ49
DQ50
DQ51
Vdd
DQ52
NC
NC
NC
Vss
DQ53
DQ54
DQ55
Vss
DQ56
DQ57
DQ58
DQ59
Vdd
DQ60
DQ61
DQ62
DQ63
Vss
CK3
NC
SA0
SA1
SA2
Vdd
Description
The Enhanced Memory Systems 256MB and 512 MB high
performance PC-133 HSDRAM DIMMs are the highest
density unbuffered SDRAM DIMMs available. Higher
density improves performance in high-end desktop
publishing, video production, and graphics applications. The
fast 4.6 ns clock access time allows unbuffered DIMM
operation at 133 MHz for lower memory latency and lower
costs than registered DIMMs.
The 256MB module (SM25608BDT-7.5) is organized as
32Mx64, and the 512MB module (SM51208BDT-7.5) is
organized as 64Mx64. The 256MB ECC module
(SM25609BDT-7.5) is organized as 32Mx72, and the
512MB ECC module (SM51209BDT-7.5) is organized as
64Mx72. 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.
Enhanced Memory Systems Inc., 1850 Ramtron Dr., Colo Spgs, CO 80921
PHONE: (800) 545-DRAM; FAX: (719) 488-9095;
http://www.edram.com
1999 Enhanced Memory Systems. All rights reserved.
The information contained herein is subject to change without notice.
Revision 1.0
Page 1 of 11
RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
