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May 1999

M27C400

4 Mbit (512Kb x8 or 256Kb x16) UV EPROM and OTP EPROM

s

5V ± 10% SUPPLY VOLTAGE in READ

OPERATION

s

ACCESS TIME: 55ns

s

BYTE-WIDE or WORD-WIDE

CONFIGURABLE

s

4 Mbit MASK ROM REPLACEMENT

s

LOW POWER CONSUMPTION

– Active Current 70mA at 8MHz

– Stand-by Current 100µA

s

PROGRAMMING VOLTAGE: 12.5V ± 0.25V

s

PROGRAMMING TIME: 100µs/word

s

ELECTRONIC SIGNATURE

– Manufacturer Code: 20h

– Device Code: B8h

DESCRIPTION

The M27C400 is an 4 Mbit EPROM offered in the

two ranges UV (ultra violet erase) and OTP (one

time programmable). It is ideally suited for micro-

processor 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 compat-

ible with the most common 8 Mbit Mask ROM.

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 rapidly to the de-

vice by following the programming procedure.

For applications where the content is programmed

only one time and erasure is not required, the

M27C400 is offered in PDIP40 package.

1

40

1

40

FDIP40W (F)

PDIP40 (B)

Figure 1. Logic Diagram

AI01634

18

A0-A17

BYTEVPP

Q0-Q14

VCC

M27C400

G

E

VSS

15

Q15A–1