
IBM11N4645BB
IBM11N4645CB
IBM11N4735BB
IBM11N4735CB
4M x 64/72 DRAM Module
50H8036.E22441E
Revised 5/98
IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
Page 9 of 31
AC Characteristics
(T
A
= 0 to +70
°
C, V
CC
=
3.3V
±
0.3V)
1. V
IH
(min) and V
IL
(max) are reference levels for measuring timing of input signals. Transition times are measured between V
IH
and
V
IL
.
2. An initial pause of 200
μ
s is required after power-up followed by 8 RAS only refresh cycles before proper device operation is
achieved. In case of using internal refresh counter, a minimum of 8 CAS before RAS refresh cycles instead of 8 RAS only refresh
cycles is required..
3. AC measurements assume t
T
= 2ns.
.
Read, Write, Read-Modify-Write and Refresh Cycles
(Common Parameters)
Symbol
Parameter
-50
-60
Unit
Notes
Min
Max
Min
Max
t
RC
Random Read or Write Cycle Time
84
—
104
—
ns
t
RP
RAS Precharge Time
30
—
40
—
ns
t
CP
CAS Precharge Time
8
—
10
—
ns
t
RAS
RAS Pulse Width
50
10K
60
10K
ns
t
CAS
CAS Pulse Width
8
10K
10
10K
ns
t
ASR
Row Address Setup Time
0
—
0
—
ns
t
RAH
Row Address Hold Time
10
—
10
—
ns
t
ASC
Column Address Setup Time
0
—
0
—
ns
t
CAH
Column Address Hold Time
8
—
10
—
ns
t
RCD
RAS to CAS Delay Time
14
37
14
45
ns
1
t
RAD
RAS to Column Address Delay Time
12
25
12
30
ns
2
t
RSH
RAS Hold Time
8
—
10
—
ns
t
CSH
CAS Hold Time
43
—
50
—
ns
t
CRP
CAS to RAS Precharge Time
5
—
5
—
ns
t
ODD
OE to D
IN
Delay Time
15
—
15
—
ns
3
t
DZO
OE Delay Time from D
IN
0
—
0
—
ns
4
t
DZC
CAS Delay Time from D
IN
0
—
0
—
ns
4
t
T
Transition Time (Rise and Fall)
2
30
2
30
ns
1. Operation within the t
RCD
(max) limit ensures that t
RAC
(max) can be met. The t
RCD
(max) is specified as a reference point only: If t
RCD
is greater than the specified t
RCD
(max) limit, then access time is controlled by t
CAC.
2. Operation within the t
RAD
(max) limit ensures that t
RAC
(max) can be met. The t
RAD
(max) is specified as a reference point only: If t
RAD
is greater than the specified t
RAD
(max) limit, then access time is controlled by t
AA.
3. Either t
CDD
or t
ODD
must be satisfied.
4. Either t
DZC
or t
DZO
must be satisfied.
Discontinued (9/98 - last order; 3/99 last ship)