168-pin Low Profile Registered SDRAM DIMMs
256MB, 512MB, 1GB
Preliminary Data Sheet
AC Operating Conditions (TA = 0°C to 70°C)
Clock and Clock Enable Parameters
Symbol
Parameter
-7.5
-10
Units
Notes
Min
Max
Min
Max
tCK2
tCK3
Clock Cycle Time, CL = 2
Clock Cycle Time, CL = 3
10.0
7.5
-
-
10.0
10.0
-
-
ns
ns
tCKH2, tCKL2 Clock High & Low Times, CL=2
tCKH3, tCKL3 Clock High & Low Times, CL=3
2.5
2.5
1.5
0.8
1.5
0.3
-
3.0
3.0
2.0
1.0
2.0
0.5
-
ns
ns
ns
ns
ns
ns
1
1
-
-
tCKES
Clock Enable Set-Up Time
-
-
-
-
tCKEH
tCKSP
tT
Clock Enable Hold Time
CKE Set-Up Time (Power down mode)
Transition Time (Rise and Fall)
-
-
1.2
2.0
Notes:
1. Assumes clock rise and fall times are equal to 1ns. If rise or fall time exceeds 1ns, other AC timing parameters must be compensated by an
additional [(trise+tfall)/2-1] ns.
Common Parameters
Symbol
Parameter
-7.5
-10
Units
Notes
Min
Max
Min
Max
tCS
Command and Address Set-Up Time
Command and Address Hold Time
RAS to CAS Delay Time
1.5
0.8
20
-
2.0
1.0
20
70
50
20
20
10
2
-
ns
ns
tCH
-
-
tRCD
tRC
tRAS
tRP
-
-
ns
Bank Cycle Time
67.5
45
-
-
ns
Bank Active Time
100K
100K
ns
Precharge Time
20
-
-
-
-
-
-
-
-
ns
tRRD
tCCD
tMRD
Bank to Bank Delay Time (Alt. Bank)
CAS to CAS Delay Time (Same Bank)
Mode Register Set to Active Delay
15
ns
7.5
2
ns
CLK
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.
Page 10
Revision 1.1
RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
