168-pin Low Profile ESDRAM DIMMs
32MB, 64MB, 128MB
Preliminary Data Sheet
Features
Pin
Symbol
Pin
Symbol
Pin
Symbol
Pin
Symbol
•
•
JEDEC Standard 168-pin SDRAM DIMM
Low Latency 166 MHz Modules (2:2:2)
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 = 2
Precharge Delay = 2
3
87
4
DQMB2
DQMB3
DNU
Vdd
88
DQMB6
DQMB7
RFU
Vdd
5
89
•
Sustained Random Burst Reads (same bank access)
6
90
•
•
1-1-1-1 at 66MHz (CL = 1)
2-1-1-1 at 166MHz (CL = 2)
7
DQ4
DQ5
DQ6
DQ7
DQ8
Vss
91
DQ36
DQ37
DQ38
DQ39
DQ40
Vss
•
•
•
•
•
•
•
Early Auto-Precharge and Pipelined Row Activation
Hidden Auto-Refresh (4K, 64ms)
Fully Synchronous Operation
On-board Serial Presence Detect (SPD)
Unbuffered 168-pin DIMM
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
CB3
95
CB7
Vss
96
Vss
Single 3.3V ± 0.3V Power Supply
Low Profile for IU Rack Mount Systems
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 SDRAM (ESDRAM) DIMMs are low
latency, high performance memory modules of 32, 64, and
128 MByte capacities, and are organized x64 or x72 bits
wide. These DIMMs are 100% pin, function, and timing
compatible with JEDEC standard 168-pin SDRAM DIMMs.
The 32 MByte and 64 MByte DIMMs employ a single
physical bank of memory while the 128 MByte DIMMs are
built as two physical banks. Within each physical bank of
memory are four logical banks, which are accessed through
the use of BA0 and BA1 (pins 122 and 39). All control,
access, and data input signals are registered into each of the
ESDRAM components through use of an external clock,
CK0-CK3.
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
NC
NC
NC
NC
Vdd
Vdd
WE#
DQMB0
DQMB1
S0#
DQ24
DQ25
DQ26
DQ27
Vdd
CAS#
DQMB4
DQMB5
S1#
DQ56
DQ57
DQ58
DQ59
Vdd
ESDRAM DIMMs provide pipeline burst SRAM
performance up to 66 MHz and nearly the same at bus
speeds up to 166 MHz. This performance is achieved using
JEDEC superset features including early auto-precharge and
pipelined row activation. The ESDRAM also supports
hidden auto-refresh.
DNU
Vss
RAS#
Vss
DQ28
DQ29
DQ30
DQ31
Vss
DQ60
DQ61
DQ62
DQ63
Vss
A0
A1
All ESDRAM DIMMs operate from a 3.3V power supply,
and all inputs and outputs are LVTTL compatible. The
DIMM has a low 1.15-inch height to support IU rack mount
system requirements. See the ESDRAM component data
sheet for
specifications and functional operation.
A2
A3
A4
A5
A6
A7
A8
CK2
A9
CK3
a more detailed discussion of ESDRAM
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
2001 Enhanced Memory Systems. All rights reserved.
The information contained herein is subject to change without notice.
Revision 1.0
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