M27C64A-10F6 STMICROELECTRONICS [STMicroelectronics], M27C64A-10F6 Datasheet - Page 9

• Manufacturer Part Number: M27C64A-10F6
• Description: 64 Kbit (8Kb x8) UV EPROM and OTP EPROM
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

M27C64A
2.5
2.6
be a high frequency capacitor of low inherent inductance and should be placed as close to
the device as possible. In addition, a 4.7µF bulk electrolytic capacitor should be used
between V
power supply connection point. The purpose of the bulk capacitor is to overcome the voltage
drop caused by the inductive effects of PCB traces.
Programming
When delivered (and after each erasure for UV EPROM), all bits of the M27C64A are in the
"1" state. Data is introduced by selectively programming "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 exposition to ultraviolet light (UV EPROM).
The M27C64A is in the programming mode when V
pulsed to V
pins. The levels required for the address and data inputs are TTL. V
± 0.25V.
High-speed programming
The high speed programming algorithm, described in
M27C64A using an efficient and reliable method, particularly suited to the production
programming environment. An individual device will take around 1 minute to program.
Figure 4.
CC
IL
. The data to be programmed is applied to 8 bits in parallel to the data output
Programming Flowchart
and V
SS
for every eight devices. The bulk capacitor should be located near the
YES
NO
> 25
FAIL
++n
V CC = 6V, V PP = 12.5V
CHECK ALL BYTES
P = 3ms Pulse by n
NO
2nd: V CC = 4.2V
1st: V CC = 6V
P = 1ms Pulse
VERIFY
n = 1
Addr
Last
YES
YES
NO
PP
Figure
input is at 12.5V, E is at V
++ Addr
AI01167
4, rapidly programs the
CC
is specified to be 6V
Device operation
IL
and P is
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