
IBM11N2645H
IBM11N2735H
2M x 64/72 DRAM MODULE
IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
Page 12 of 31
50H7623.E93788
Released 5/98
Read-Modify-Write Cycle
Symbol
Parameter
-50
-60
Unit
Notes
Min
Max
Min
Max
t
RWC
Read-Modify-Write Cycle Time
110
—
135
—
ns
t
RWD
RAS to WE Delay Time
67
—
79
—
ns
1
t
CWD
CAS to WE Delay Time
30
—
34
—
ns
1
t
AWD
Column Address to WE Delay Time
42
—
49
—
ns
1
t
OEH
OE Command Hold Time
7
—
10
—
ns
1. t
WCS
, t
RWD
, t
CWD
, and t
AWD
are not restrictive parameters. They are included in the data sheet as electrical characteristics only. If
t
WCS
≥
t
WCS
(min.), the entire cycle is an early write cycle and the data pin will remain open circuit (high impedance) through the
entire cycle; If t
RWD
≥
t
RWD
(min.), t
CWD
≥
t
CWD
(min.) and t
AWD
≥
t
AWD
(min.), the cycle is a Read-Modify-Write cycle and the data will
contain read from the selected cell: If neither of the above sets of conditions are met, the condition of the data (at access time) is
indeterminate.
EDO Mode Cycle
Symbol
Parameter
-50
-60
Units
Notes
Min.
Max.
Min.
Max.
t
HCAS
CAS Pulse Width (EDO Page Mode)
8
10K
10
10K
ns
t
HPC
EDO Page Mode Cycle Time (Read/Write)
20
—
25
—
ns
t
HPRWC
EDO Page Mode Read Modify Write Cycle Time
51
—
60
—
ns
t
DOH
Data-out Hold Time from CAS
5
—
5
—
ns
t
WHZ
Output buffer Turn-Off Delay from WE
0
10
0
10
ns
t
WPZ
WE Pulse Width to Output Disable at CAS High
7
—
10
—
ns
t
CPRH
RAS Hold Time from CAS Precharge
30
—
35
—
ns
t
CPA
Access Time from CAS Precharge
—
28
—
35
ns
1
t
RASP
EDO Page Mode RAS Pulse Width
50
125K
60
125K
ns
t
OEP
OE High Pulse Width
5
—
10
—
ns
t
OEHC
OE High Hold Time from CAS High
5
—
10
—
ns
1. Measured with the specified current load and 100pF at V
OL
= 0.8V and V
OH
= 2.0V.
Discontinued (9/98 - last order; 3/99 last ship)