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KM416C4000C,
KM416C4100C
CMOS DRAM
KM416C40(1)00C Truth Table
RAS
H
LCAS
X
UCAS
X
W
X
OE
X
DQ0 - DQ7
Hi-Z
DQ8-DQ15
Hi-Z
STATE
Standby
L
H
H
X
X
Hi-Z
Hi-Z
Refresh
L
L
L
H
H
L
H
H
L
L
DQ-OUT
Hi-Z
Hi-Z
Byte Read
Byte Read
DQ-OUT
L
L
L
H
L
DQ-OUT
DQ-OUT
Word Read
L
L
H
L
H
DQ-IN
-
Byte Write
L
L
H
L
L
L
L
L
H
H
-
DQ-IN
DQ-IN
Byte Write
Word Write
DQ-IN
L
L
L
H
H
Hi-Z
Hi-Z
-
NOTES
An initial pause of 200
us
is required after power-up followed by any 8 RAS-only refresh or CAS-before-RAS refresh cycles
before proper device operation is achieved.
V
IH
(min) and V
IL
(max) are reference levels for measuring timing of input signals. Transition times are measured between
V
IH
(min) and V
IL
(max) and are assumed to be 5ns for all inputs.
Measured with a load equivalent to 2 TTL load and 100pF.
Operation within the
t
RCD
(max) limit insures that
t
RAC
(max) can be met,
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 exclusively by
t
CAC
.
Assumes that
t
RCD
≥
t
RCD
(max).
t
OFF
(min)and
t
OEZ
(max) define the time at which the output achieves the open circuit condition and are not referenced V
oh
or V
ol
.
t
WCS
,
t
RWD
,
t
CWD
and
t
AWD
are non restrictive operating parameters. They are included in the data sheet as electrical char-
acteristics only. If
t
WCS
≥
t
WCS
(min), the cycle is an early write cycle and the data output will remain high impedance for the
duration of the cycle. If
t
CWD
≥
t
CWD
(min),
t
RWD
≥
t
RWD
(min) and
t
AWD
≥
t
AWD
(min), then the cycle is a read-modify-write cycle
and the data output will contain the data read from the selected address. If neither of the above conditions is satisfied, the
condition of the data out is indeterminate.
Either
t
RCH
or
t
RRH
must be satisfied for a read cycle.
These parameters are referenced to CAS falling edge in early write cycles and to W falling edge in read-modify-write cycles.
Operation within the
t
RAD
(max) limit insures that
t
RAC
(max) can be met.
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
.
These specifications are applied in the test mode.
In test mode read cycle, the value of
t
RAC
,
t
AA
,
t
CAC
is delayed by 2ns to 5ns for the specified values. These parameters
should be specified in test mode cycles by adding the above value to the specified value in this data sheet.
5.
6.
7.
8.
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10.
11.
12.
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