AMD27C64-120DC AMD [Advanced Micro Devices], AMD27C64-120DC Datasheet - Page 6

• Manufacturer Part Number: AMD27C64-120DC
• Description: 64 Kilobit (8,192 x 8-Bit) CMOS EPROM
• Manufacturer: AMD [Advanced Micro Devices]

Output OR-Tieing
To accommodate multiple memory connections, a two-
line control function is provided to allow for:
It is recommended that CE be decoded and used as the
primary device-selecting function, while OE be made a
common connection to all devices in the array and con-
nected to the READ line from the system control bus.
This assures that all deselected memory devices are in
low-power standby mode and that the output pins are
only active when data is desired from a particular
memory device.
MODE SELECT TABLE
Notes:
1. V
2. X = Either V
3. A1–A8 = A10–A12 = V
4. See DC Programming Characteristics for V
Mode
Read
Output Disable
Standby (TTL)
Standby (CMOS)
Program
Program Verify
Program Inhibit
Low memory power dissipation
Assurance that output bus contention will not occur
Auto Select
H
(Note 3)
= 12.0 V
IH
0.5 V
or V
Manufacturer
Code
Device Code
IL
IL
Pins
V
CC
CE
V
V
V
V
V
V
V
X
IH
IH
IL
IL
IL
IL
IL
0.3 V
PP
voltage during programming.
Am27C64
OE
V
V
V
V
V
X
X
X
X
IH
IL
IL
IL
IL
System Applications
During the switch between active and standby condi-
tions, transient current peaks are produced on the rising
and falling edges of Chip Enable. The magnitude of
these transient current peaks is dependent on the out-
put capacitance loading of the device. At a minimum, a
0.1- F ceramic capacitor (high frequency, low inherent
inductance) should be used on each device between
V
overcome the voltage drop caused by the inductive ef-
fects of the printed circuit board traces on EPROM ar-
rays, a 4.7- F bulk electrolytic capacitor should be used
between V
tion of the capacitor should be close to where the power
supply is connected to the array.
CC
PGM
V
V
X
X
X
X
X
X
X
and V
IH
IL
SS
CC
V
A0
V
to minimize transient effects. In addition, to
X
X
X
X
X
X
X
IH
and V
IL
SS
A9
V
V
for each eight devices. The loca-
X
X
X
X
X
X
X
H
H
V
V
V
VPP
X
X
X
X
X
X
PP
PP
PP
Outputs
High-Z
High-Z
High-Z
High-Z
D
D
01H
15H
D
OUT
OUT
AMD
IN
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