M27C64A-10F1 STMicroelectronics, M27C64A-10F1 Datasheet - Page 10

• Manufacturer Part Number: M27C64A-10F1
• Description: IC EPROM 64KBIT 100NS 28CDIP
• Manufacturer: STMicroelectronics

Specifications of M27C64A-10F1

• Format - Memory: EPROMs
• Memory Type: UV EPROM
• Memory Size: 64K (8K x 8)
• Speed: 100ns
• Interface: Parallel
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-CDIP (0.600", 15.24mm) Window
• Memory Configuration: 8K X 8
• Access Time: 100ns
• Supply Voltage Range: 4.5V To 5V
• Memory Case Style: DIP
• No. Of Pins: 28
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-1684-5

M27C64A
Electronic Signature
The Electronic Signature (ES) mode allows the
reading out of a binary code from an EPROM that
will identify its manufacturer and type. This mode
is intended for use by programming equipment to
automatically match the device to be programmed
with its corresponding programming algorithm.
The ES mode is functional in the 25°C ± 5°C am-
bient temperature range that is required when pro-
gramming the M27C64A. To activate the ES
mode, the programming equipment must force
11.5V to 12.5V on address line A9 of the
M27C64A, with V
bytes may then be sequenced from the device out-
puts by toggling address line A0 from V
other address lines must be held at V
Electronic Signature mode.
Byte 0 (A0 = V
code and byte 1 (A0=V
code. For the STMicroelectronics M27C64A,
these two identifier bytes are given in Table 4 and
can be read-out on outputs Q7 to Q0.
10/14
IL
PP
) represents the manufacturer
= V
IH
CC
) the device identifier
= 5V. Two identifier
IL
to V
IL
during
IH
. All
ERASURE OPERATION (applies to UV EPROM)
The erasure characteristics of the M27C64A is
such that erasure begins when the cells are ex-
posed to light with wavelengths shorter than ap-
proximately 4000 Å. It should be noted that
sunlight and some type of fluorescent lamps have
wavelengths in the 3000-4000 Å range. Research
shows that constant exposure to room level fluo-
rescent lighting could erase a typical M27C64A in
about 3 years, while it would take approximately 1
week to cause erasure when exposed to direct
sunlight. If the M27C64A is to be exposed to these
types of lighting conditions for extended periods of
time, it is suggested that opaque labels be put over
the M27C64A window to prevent unintentional
erasure. The recommended erasure procedure for
the M27C64A is exposure to short wave ultraviolet
light which has a wavelength of 2537 Å. The inte-
grated dose (i.e. UV intensity x exposure time) for
erasure should be a minimum of 15 W-sec/cm
The erasure time with this dosage is approximate-
ly 15 to 20 minutes using an ultraviolet lamp with
12000 µW/cm
should be placed within 2.5 cm (1 inch) of the lamp
tubes during the erasure. Some lamps have a filter
on their tubes which should be removed before
erasure.
2
power rating. The M27C64A
2
.