CAT28C256
MODE SELECTION
Mode
Read
Byte Write (WE Controlled)
Byte Write (CE Controlled)
Standby, and Write Inhibit
Read and Write Inhibit
H
X
CE
L
L
L
X
H
WE
H
OE
L
H
H
X
H
I/O
D
OUT
D
IN
D
IN
High-Z
High-Z
Power
ACTIVE
ACTIVE
ACTIVE
STANDBY
ACTIVE
CAPACITANCE
T
A
= 25°C, f = 1.0 MHz, V
CC
= 5V
Symbol
C
I/O(1)
C
IN(1)
Test
Input/Output Capacitance
Input Capacitance
Max.
10
6
Units
pF
pF
Conditions
V
I/O
= 0V
V
IN
= 0V
A.C. CHARACTERISTICS, Read Cycle
V
CC
=5V + 10%, Unless otherwise specified
28C256-12
Min. Max.
120
120
120
50
0
0
50
50
0
0
0
0
50
50
28C256-15
Min. Max.
150
150
150
70
Symbol
t
RC
t
CE
t
AA
t
OE
t
LZ(1)
t
OLZ(1)
t
HZ(1)(2)
t
OHZ(1)(2)
t
OH(1)
Parameter
Read Cycle Time
CE
Access Time
Address Access Time
OE
Access Time
CE
Low to Active Output
OE
Low to Active Output
CE
High to High-Z Output
OE
High to High-Z Output
Output Hold from Address Change
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
Note:
(1) This parameter is tested initially and after a design or process change that affects the parameter.
(2) Output floating (High-Z) is defined as the state when the external data line is no longer driven by the output buffer.
Doc. No. 25020-0A 2/98
4