M27C512 STMicroelectronics, M27C512 Datasheet - Page 6

• Manufacturer Part Number: M27C512
• Description: 512 Kbit 64Kb x8 UV EPROM and OTP EPROM
• Manufacturer: STMicroelectronics

M27C512
Table 8B. Read Mode AC Characteristics
(T
Notes. 1. V
Figure 5. Read Mode AC Waveforms
Programming
When delivered (and after each erasure for UV
EPROM), all bits of the M27C512 are in the ’1’
state. Data is introduced by selectively program-
ming ’0’s into the desired bit locations. Although
only ’0’s will be programmed, both ’1’s and ’0’s can
be present in the data word. The only way to
change a ’0’ to a ’1’ is by die exposure to ultraviolet
light (UV EPROM). The M27C512 is in the pro-
gramming mode when V
6/15
Symbol
t
t
EHQZ
GHQZ
A
t
t
t
t
GLQV
AXQX
AVQV
ELQV
= 0 to 70 C, –40 to 85 C or –40 to 125 C; V
2. Sampled only, not 100% tested.
(2)
(2)
CC
Q0-Q7
A0-A15
E
G
must be applied simultaneously with or before V
t
t
Alt
ACC
t
t
t
t
CE
OE
OH
DF
DF
Address Valid to
Output Valid
Chip Enable Low to
Output Valid
Output Enable Low
to Output Valid
Chip Enable High to
Output Hi-Z
Output Enable High
to Output Hi-Z
Address Transition
to
Output Transition
Parameter
PP
input is at 12.75V and
tAVQV
tELQV
Test Condition
E = V
E = V
tGLQV
VALID
G = V
G = V
E = V
E = V
IL
IL
, G = V
, G = V
(1)
IL
IL
IL
IL
PP
and removed simultaneously or after V
IL
IL
CC
= 5V
Min Max Min Max Min Max
0
0
0
E is pulsed to V
applied to 8 bits in parallel to the data output pins.
The levels required for the address and data inputs
are TTL. V
The M27C512 can use PRESTO IIB Programming
Algorithm that drastically reduces the programming
time (typically less than 6 seconds). Nevertheless
to achieve compatibility with all programming
equipments, PRESTO Programming Algorithm can
be used as well.
-90
90
90
40
30
30
5% or 5V
0
0
0
CC
tAXQX
-10
is specified to be 6.25V
100
100
40
30
30
M27C512
IL
10%; V
. The data to be programmed is
tGHQZ
tEHQZ
VALID
0
0
0
PP
-12
.
PP
120
120
50
40
40
= V
CC
Min
-15/-20/-25
)
0
0
0
AI00735B
Hi-Z
Max
150
150
60
50
50
0.25V.
Unit
ns
ns
ns
ns
ns
ns