m27128a STMicroelectronics, m27128a Datasheet - Page 2

• Manufacturer Part Number: m27128a
• Description: Nmos 128k 16k X 8 Uv Eprom
• Manufacturer: STMicroelectronics

Table 2. Absolute Maximum Ratings
Note: Except for the rating "Operating Temperature Range", stresses above those listed in the Table "Absolute Maximum Ratings" may cause
permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those
indicated in the Operating sections of this specification is not implied. Exposure to Absolute Maximum Rating conditions for extended periods
may affect device reliability. Refer also to the SGS-THOMSON SURE Program and other relevant quality documents.
DEVICE OPERATION
The seven modes of operation of the M27128A are
listed in the Operating Modes table. A single 5V
power supply is required in the read mode. All
inputs are TTL levels except for V
for Electronic Signature.
M27128A
Figure 2. DIP Pin Connections
2/10
Symbol
T
T
V
V
V
V
T
BIAS
STG
CC
PP
A9
IO
A
V PP
V SS
A12
Q0
Q1
Q2
A7
A6
A5
A4
A3
A2
A1
A0
Ambient Operating Temperature
Temperature Under Bias
Storage Temperature
Input or Output Voltages
Supply Voltage
A9 Voltage
Program Supply
1
2
3
4
5
6
7
8
9
10
11
12
13
14
M27128A
AI00770
28
27
26
25
24
23
22
21
20
19
18
17
16
15
PP
Parameter
V CC
P
A13
A8
A9
A11
G
A10
E
Q7
Q6
Q5
Q4
Q3
and 12V on A9
Read Mode
The M27128A has two control functions, both of
which must be logically satisfied in order to obtain
data at the outputs. Chip Enable (E) is the power
control and should be used for device selection.
Output Enable (G) is the output control and should
be used to gate data to the output pins, inde-
pendent of device selection.
Assuming that the addresses are stable, address
access time (t
output (t
the falling edge of G, assuming that E has been low
and the addresses have been stable for at least
t
Standby Mode
The M27128A has a standby mode which reduces
the maximum active power current from 85mA to
40mA. The M27128A is placed in the standby mode
by applying a TTL high signal to the E input. When
in the standby mode, the outputs are in a high
impedance state, independent of the G input.
Two Line Output Control
Because EPROMs are usually used in larger mem-
ory arrays, this product features a 2 line control
function which accommodates the use of multiple
memory connection. The two line control function
allows:
a. the lowest possible memory power dissipation,
b. complete assurance that output bus contention
grade 1
grade 6
grade 1
grade 6
AVQV
will not occur.
-t
GLQV
ELQV
.
). Data is available at the outputs after
AVQV
–0.6 to 6.25
–0.6 to 13.5
–0.6 to 14
–0.6 to 6.25
–40 to 85
–10 to 80
–50 to 95
–65 to 125
) is equal to the delay from E to
0 to 70
Value
Unit
V
V
V
V
C
C
C