Preliminary Data Sheet
PC-133 HSDRAM
256MB, 512MB DIMM
256MB DIMM Functional Block Diagram – SM25608BDT-7.5
S0#
Clock Wiring
DQMB0
U1
DQ(7:0)
DQMB4
U5
DQ(39:32)
CK0
CK1
CK2
CK3
4 SDRAM+3.3 pf
Termination
4 SDRAM+3.3 pf
Termination
10
CK0,2
SDRAMs
DQMB1
U2
DQ(15:8)
DQMB5
U6
DQ(47:40)
CK1,3
10 pf
Clock Termination
10
S2#
DQMB2
U3
DQ(23:16)
DQMB6
U7
DQ(55:48)
SCL
SA0-2
SDA
Serial PD
WP
47K
DQMB3
U4
DQ(31:24)
DQMB7
U8
DQ(63:56)
BA0
BA1
A0-A12
Vdd
Vss
BA0 SDRAM U1-8
BA1 SDRAM U1-8
A0-A12 SDRAM U1-8
Vdd SDRAM U1-8
Vss SDRAM U1-8
RAS#
CAS#
WE#
CKE0
RAS# SDRAM U1-8
CAS# SDRAM U1-8
WE# SDRAM U1-8
CKE0 SDRAM U1-8
Note: All DQ resistor values are 10 ohms
All CK resistor values are 10 ohms
U1-U8 are SM3803T
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 3 of 11
RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
