M27W400
4 Mbit (512Kb x8 or 256Kb x16)
Low Voltage UV EPROM and OTP EPROM
s
2.7 to 3.6V LOW VOLTAGE in READ
OPERATION
READ ACCESS TIME:
鈥?80ns at V
CC
= 3.0 to 3.6V
鈥?100ns at V
CC
= 2.7 to 3.6V
40
40
s
s
BYTE-WIDE or WORD-WIDE
CONFIGURABLE
4 Mbit MASK ROM REPLACEMENT
LOW POWER CONSUMPTION
鈥?Active Current 20mA at 8MHz
鈥?Stand-by Current 15碌A(chǔ)
1
1
FDIP40W (F)
PDIP40 (B)
s
s
s
s
s
PROGRAMMING VOLTAGE: 12.5V 鹵 0.25V
PROGRAMMING TIME: 50碌s/word
ELECTRONIC SIGNATURE
鈥?Manufacturer Code: 20h
鈥?Device Code: B8h
Figure 1. Logic Diagram
PLCC44 (K)
DESCRIPTION
The M27W400 is a low voltage 4 Mbit EPROM of-
fered in the two range UV (Ultra Violet Erase) and
OTP (one time programmable). It is ideally suited
for microprocessor systems requiring large data or
program storage. It is organised as either 512
Kwords of 8 bit or 256 Kwords of 16 bit. The pin-
out is compatible with the most common 4 Mbit
Mask ROM.
The M27W400 operates in the read mode with a
supply voltage as low as 2.7V at 鈥?0 to 85擄C tem-
perature range. The decrease in operating power
allows either a reduction of the size of the battery
or an increase in the time between battery re-
charges.
The FDIP40W (window ceramic frit-seal package)
has a transparent lid which allows the user to ex-
pose the chip to ultraviolet light to erase the bit pat-
tern. A new pattern can then be written to the
device by following the programming procedure.
For application where the content is programmed
only one time and erasure is not required, the
M27W400 is offered in PDIP40 and PLCC44 pack-
ages.
VCC
18
A0-A17
15
Q15A鈥?
Q0-Q14
E
G
BYTEVPP
M27W400
VSS
AI03096
January 2000
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