SGS Thomson Microelectronics M27512-F6, M27512-F1, M27512-3F6, M27512-3F1, M27512-2F1 Datasheet

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NOT FOR NEW DESIGN

November 2000

This is information on a product still in production but not recommended for new designs.

M27512

NMOS 512 K bit (6 4Kb x 8) UV EPROM

■ FAST ACCESS TIME: 200ns

■ EXTENDED TEMPERATURE RANGE

■ SINGLE 5V SUPPLY VOLTAGE

■ LOW STANDBY CURRENT: 40mA max

■ TTL COMPATIBLE DURING READ and

PROGRAM

■ FAST PROGRAMMING ALGORITHM

■ ELECTRONIC SIGNATURE

■ PROGRAMMING VOLTAGE: 12V

DESCRIPTION

The M27512 is a 524,288 bit UV erasable and
electrically programmable memory EPRO M. It is
organized as 65,536 words by 8 bits.

The M27512 is housed in a 28 Pin Window Ce­ramic Frit-Seal Dual-in-Line package. The trans­parent lid allows the user to expose the chip to
ultraviolet light to erase the bit pattern. A new pat­tern can then be written to the device by following
the programming procedure.

Figure 1. Logic Diagram

AI00765B

16

Q0-Q7

V

CC

M27512

GV

PP

V

SS

8

A0-A15

E

1

28

FDIP28W (F)

A1
A0

Q0

A7

A4
A3
A2

A6
A5

A13

A10

A8
A9

Q7

A14

A11
GV

PP

E

Q5Q1

Q2

Q3V

SS

Q4

Q6

A12

A15 V

CC

AI00766

M27512

8

1
2
3
4
5
6
7

9
10
11
12
13
14

16
15

28
27
26
25
24
23
22
21
20
19
18
17

Figure 2. DIP Pin Co n nect ion s

Symbol Parameter Value Unit

T

A

Ambient Operating T empera ture

Grade 1
Grade 6

0 to 70

–40 to 85

°C

T

BIAS

Temperature Under Bias

Grade 1
Grade 6

–10 to 80
–50 to 95

°C

T

STG

Storage Temperature –65 to 125 °C

V

IO

Input or Output Voltages –0.6 to 6.5 V

V

CC

Supply Voltage –0.6 to 6.5 V

V

A9

A9 Voltage –0.6 to 13.5 V

V

PP

Program Supply –0.6 to 14 V

Note: Except for the rating "Operating Temperature Range", st resses above t hose listed in t he Ta ble "Absolute Max imum R atings" may c ause
permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those
indicated in the Operating sections of this specification is not implied. Exposure to Absolute Maximum Ratin g conditions for extended periods
may affect device reliability. Refer also to the STMicroelectronics SURE Program and other relevant quality document.

Table 2. Absol ute Maxim u m Ratin g s

DEVICE OPERATION

The six modes of operations of the M27512 are
listed in the Operating Modes table. A single 5V
power supply is required in the read mode. All
inputs are TTL levels except for

GVPP and 12V on

A9 for Electronic Signature.

Read Mode

The M27512 has two control functions, both of
which must be logically active in order to obtain
data at the outputs. Chip Enable (

E) is the power
control and should be used for device selection.
Output Enable (

G) is the output control and should
be used to gate data to the output pins, inde­pendent of device selection. Assuming that the
addresses are s table, address access time (t

AVQV

)

is equal to the delay from

E to output (t

ELQV

). Data

is available at the out puts after d elay of t

GLQV

from

the falling edge of

G, assuming that E has been low
and the addresses have been stable for at least
t

AVQ V-tGLQV

.

Stand by Mod e

The M27512 has a standby mode which reduces
the maximum active power current f rom 125m A to
40mA. The M27512 is placed in the standby mod e
by applying a TTL high signal to the

E input. Wh en
in the standby mode, the outputs are in a high
impedance state, independent of the

GVPP input.

Two Line Output Control

Because EPROM s are usually used in larger mem­ory arrays, the product features a 2 line control
function which accommodates the use of multiple
memory connection. The two line control function
allows :

a. the lowest possible memory power dissipation,
b. complete assurance that output bus c ontent io n

will not occur.

M27512

2/11

For the most efficient us e of these two control lines,
E should be decoded and used as the primary
device selecting function, while

GVPP should be
made a common connection to all devices in the
array and connected to the

READ line from the
system control bus. This ensures that all dese­lected memory devices are in their low power
standby mode and that the output pins are only
active when data is r equired from a particular mem­ory device.

System Considerati on s

The power switching characteristics of fast
EPROMs require careful decoupling of the devices.

The supply current, I

CC

, has three segments that
are of interes t to the s ystem designer : the s tandby
current level, the active c urrent level, and t ransient
current peaks that are produced by the falling and
rising edges of

E. The magnitude of the transient
current peaks is dependent on the capacitive and
inductive loading of the device at the output. The
associated transient voltage peaks can be sup­pressed by complying with the two line output
control and by properly selected decoupling ca­pacitors. It is recommenced that a 1µF ceramic
capacitor be used on every device between V

CC

and VSS. This should 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

CC

and VSS for every eight devices. Th e

bulk capacitor should be located near the power
supply connection point. The purpose of the bulk
capacitor is to overcome the voltage drop caused
by the inductive effects of PC B trac es.

Programming

When delivered, and after each erasure, all bits of
the M27512 are in the “1" stat e. Data is intr oduce d
by selectively programming ”0s" into the desired bit
locations. Although only “0s” will be programmed,
both “1s” and “0s” can be present in the dat a word.
The only way to change a “0" to a ”1" is by ultraviolet
light erasure. The M27512 is in the programming
mode when

GVPP input is at 12.5V and E is at
TTL-low. The data to be programmed is applied 8
bits in parallel to the data output pins. The levels
required for the address and data inputs are TTL.
The M27512 can us e PRESTO P rogramming Algo­rithm that drastically reduces the programming
time (typically less than 50 seconds). Never theless
to achieve compatibility with all programming
equipment, the standard Fast Programming Algo­rithm may also be used.

Fast Prog rammi ng Alg or ithm

Fast Programming Algorithm rapidly programs
M27512 EPROMs using an efficient and reliable
method suited to the production programming en­vironment. Programming reliability is also ens ured
as the incremental program margin of each byte is
continually monitored to determine when it has
been successfully program med. A flowc hart of the
M27512 Fast Programming Algorithm is shown in
Figure 8.

Mode E GV

PP

A9 Q0 - Q7

Read V

IL

V

IL

X Data Out

Output Disable V

IL

V

IH

X Hi-Z

Program V

IL

Pulse V

PP

X Data In

Verify V

IH

V

IL

X Data Out

Program Inhibit V

IH

V

PP

X Hi-Z

Standby V

IH

X X Hi-Z

Electronic Signature V

IL

V

IL

V

ID

Codes

Note: X = VIH or VIL, VID = 12V ± 0.5%.

Table 3. Operating Modes

Identifier A0 Q7 Q6 Q5 Q4 Q3 Q2 Q1 Q0 Hex Data

Manufacturer’s Code V

IL

00100000 20h

Device Code V

IH

00001101 0Dh

T a b le 4. Electro ni c Sig n atu r e

DEVICE OPERATION (cont’d)

M27512

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AI00827

2.4V

0.45V

2.0V

0.8V

Figure 3. AC T est ing Input Ou tput Waveform s

Input Rise and Fall Times ≤ 20ns
Input Pulse Voltages 0.45V to 2.4V
Input and Output Timing Ref. Voltages 0.8V to 2.0V

AC MEASUREMENT CONDITIONS

AI00828

1.3V

OUT

CL = 100pF

CL includes JIG capacitance

3.3kΩ

1N914

DEVICE
UNDER

TEST

Figure 4. AC Testing L oad Circui t

Note that Output Hi-Z is defined as the point where data
is no longer driven.

Symbol Parameter Test Condition Min Max Unit

C

IN

Input Capacitance VIN = 0V 6 pF

C

OUT

Output Capacitance V

OUT

= 0V 12 pF

Note: 1. Sampled only, not 100% tested.

T able 5. Capacitance

(1)

(TA = 25 °C, f = 1 MHz )

AI00735

tAXQX

tEHQZ

DATA OUT

A0-A15

E

G

Q0-Q7

tAVQV

tGHQZ

tGLQV

tELQV

VALID

Hi-Z

Figure 5. Read Mode AC Wav efo rm s

M27512

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