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A.1.1.3 27512
# -
The 27512 is an EPROM,
which is an ultra-violet erasable and electrically programmable
ROM.
Features:
●
65536 words X 8 bits
28
2
27
●
TTL compatible input/output
3
●
single power
4
2 5
●
Acccess time: 200 ns (max.)
5
24
23 A
I I
‘
●
28 pins (DIP)
7
2 2
8
2 1
Terminal Functions:
20
●
●
●
●
●
AO to Al 5: Address input
Chip enable input
Output enable input/programming power supply
00 to 07: Data output
10
19
00 11
12
17
01
04
1 4
15
Power supply (+5 V)
Figure A-10. 27512 Pin
Ground
Vet
02
04
01
?
?
?
?
?
?
7
?
Circuit
Output
I
I
6
Column
Decoder
Column Gate
A
Z
I
A4
Buffer
10
Row
1 0 2 4
Decoder
Figure A-1 1. 27512 Block Diagram
Table A-4. 27512 Signal Status
Diagram
Vcc
0 0 - 0 7
Mode
(28)
(22)
(20)
(1 1 - 13, 15 - 19)
Power
Read
L
L
Data output
Active
Output disable
5V
I
*
impedance
Standby
*
I
H
High impedance
Standby
—
.
Program
L
Data input
Program inhibit
6 V
VPP
H
H i g h i m p e d a n c e
A c t i v e
P r o g r a m v e r i f y
L
L
D a t a o u t p u t
* :
o r
A-1 2
Summary of Contents for LQ-2550
Page 1: ...L Q 2 5 5 0 TECHNICAL MANUAL EPSON ...
Page 240: ...REV A P r cl Figure 6 3 LQ 2550 Lubrication and Adhesive Application Points Diagram 2 6 3 ...
Page 241: ...REV A 7 i_ Figure 6 4 LQ 2550 Lubrication and Adhesive Application Points Diagram 3 6 4 ...
Page 252: ...REV A I 1 I 7 v m o m x b Figure A 6 PPD781OHG Block Diagram A 7 ...
Page 297: ...REV A 1 L I Irl N I i t 1 I I x Figure A 50 ROPSE Board Circuit Diagram A 52 ...