M27V101-90N6TR STMicroelectronics, M27V101-90N6TR Datasheet - Page 9

• Manufacturer Part Number: M27V101-90N6TR
• Description: 1 Mbit 128Kb x 8 Low Voltage UV EPROM and OTP EPROM
• Manufacturer: STMicroelectronics

and G at V
6.25V.
On-Board Programming
The M27V102 can be directly programmed in the
application circuit. See the relevant Application
Note AN620.
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 correspondingprogramming algorithm. The
ES mode is functional in the 25 C
temperature range that is required when program-
ming the M27V102. To activate the ES mode, the
programming equipmentmust force 11.5Vto 12.5V
on address line A9 of the M27V102 with V
= 5V. Two identifier bytes may then be sequenced
from the device outputs by togglingaddress line A0
from V
at V
(A0=V
byte 1 (A0=V
STMicroelectronics M27V102, these two iden-tifier
bytes are given in Table 4 and can be read-out on
outputs Q0 to Q7. Note that the M27V102 and
M27C1024 have the same identifier bytes.
IL
IL
IL
during Electronic Signature mode. Byte 0
) represents the manufacturer code and
to V
IL
IH
, P at V
IH
. All other address lines must be held
) the device identifier code. For the
IH
, V
PP
at 12.75V and V
5 C ambient
PP
= V
CC
CC
at
ERASURE OPERATION (applies to UV EPROM)
Theerasure characteristics of the M27V102is such
that erasure begins when the cells are exposed to
light with wavelengths shorter than approximately
4000 Å. It should be noted that sunlight and some
type of fluorescent lamps have wavelengths in the
3000-4000Å range. Research shows that constant
exposure to room level fluorescent lighting could
erase a typical M27V102 in about 3 years, while it
would take approximately 1 week to cause erasure
when exposed to direct sunlight. If the M27V102
is to be exposed to these types of lighting condi-
tions for extended periods of time, it is suggested
that opaque labels be put over the M27V102 win-
dow to prevent unintentionalerasure. The recom-
mended erasure procedure for the M27V102 is
exposure to short wave ultraviolet light which has
wavelength 2537 Å. The integrated dose (i.e. UV
intensity x exposure time) for erasure should be a
minimum of 15 W-sec/cm
this dosage is approximately 15 to 20 minutes
using an ultravioletlamp with 12000 W/cm
rating. The M27V102 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
. The erasure time with
M27V102
2
power
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