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CY27C256
4
AC Test Loads and Waveforms
27c256–6
27c256–7
90%
10%
3.0V
GND
90%
10%
ALL INPUT PULSES
5V
OUTPUT
30 pF
INCLUDING
JIG AND
SCOPE
5V
OUTPUT
5 pF
INCLUDING
JIG AND
SCOPE
(a) Normal Load
(b) High Z Load
5ns
5 ns
OUTPUT
R1 250
Ω (329Ω MIL)
R2 167
Ω
(202
Ω MIL)
100
Ω
Equivalent to:
THÉVENIN EQUIVALENT
2.00V
R2 167
Ω
(202
Ω MIL)
R1 250
Ω (329Ω MIL)
OUTPUT
125
Ω
1.9V
Commercial
Military
≤
≤
Switching Characteristics Over the Operating Range[4,7 ]
27C256-45
27C256-
55
27C256-70
27C256-90
Parameter
Description
Min.
Max.
Min.
Max.
Min.
Max.
Min.
Max.
Unit
tAA
Address to Output Valid
45
55
70
90
ns
tHZOE
Outpout Enable Inactive to High Z
15
20
25
25
ns
tOE
Output Enable Active to Output Valid
15
20
25
30
ns
tHZCE
Chip Enable Inactive to High Z
20
25
25
25
ns
tACE
Chip Enable Active to Output Valid
45
55
70
90
ns
tPU
Chip Enable Active to Power Up
0
0
0
0
ns
tPD
Chip Enable Inactive to Power Down
45
55
70
90
ns
tOH
Output Hold from Address Change
0
0
0
0
ns
Switching Characteristics Over the Operating Range[4, 7]
27C256-120
27C256-150
27C256-200
Parameter
Description
Min.
Max.
Min.
Max.
Min.
Max.
Unit
tAA
Address to Output Valid
120
150
200
ns
tHZOE
Outpout Enable Inactive to High Z
30
30
30
ns
tOE
Output Enable Active to Output Valid
30
40
40
ns
tHZCE
Chip Enable Inactive to High Z
30
30
30
ns
tACE
Chip Enable Active to Output Valid
120
150
200
ns
tPU
Chip Enable Active to Power Up
0
0
0
ns
tPD
Chip Enable Inactive to Power Down
120
150
200
ns
tOH
Output Hold from Address Change
0
0
0
ns