DESCRIPTION

The Accutek AK491024 high density memory module is a random

access memory organized in 1 Meg x 9 bit words. The assembly

consists of nine standard 1 Meg x 1 DRAMs in plastic leaded chip

carriers (SOJ) mounted on the front side of a printed circuit board.

The module can be configured as a leadless 30 pad SIM or a leaded

30 pin SIP. This packaging approach provides a 6 to 1 density in-

crease over standard DIP packaging.

The operation of the AK491024 is identical to nine 1 Meg x 1

DRAMs. For the lower eight bits data input is tied to the data output

and brought out separately for each device, with common RAS,

CAS control.

This common I/O feature dictates the use of

early-write cycles to prevent contention of D and Q. Since the

Write-Enable (WE) signal must always go low before CAS in a write

cycle, Read-Write and Read-Modify-Write operation is not possible.

brought out separately and controlled by a separate PCAS for that

bit. Bit nine is generally used for parity.

FEATURES

· 1,048,576 x 9 bit organization

· Optional 30 Pad leadless SIM (Single In-Line Module) or 30

Pin leaded SIP (Single In-Line Package)

· JEDEC standard pinout

· Common CAS and RAS control for the lower eight bits

· CAS-before-RAS refresh

· Power

3.465 Watt Max Active (80 nSEC)

2.97 Watt Max Active (100 nSEC)

2.475 Watt Max Active (120 nSEC)

49.5 mW Max Standby

· Operating free air temperature 0

· Upward compatible with AK594096 and AK5916384

· Downward compatible with AK49256

Accutek

Microcircuit

Corporation

AK491024S / AK491024G

1,048,576 Word x 9 Bit CMOS

Dynamic Random Access Memory

1

30

1

Front View

30-Pin SIM

30-Pin SIP

PIN NOMENCLATURE

Data In / Data Out

Data In 9

Data Out 9

Address Inputs

CAS, PCAS

Column Address Strobe

RAS

Row Address Strobe

WE

Write Enable

Vcc

5v Supply

Vss

Ground

NC

No Connect

MODULE OPTIONS

Leadless SIM: AK491024S

Leaded SIP: AK491024G

PIN ASSIGNMENT

PIN #

SYMBOL

PIN #

SYMBOL

1

Vcc

16

DQ5

2

CAS

17

A8

3

DQ1

18

A9

4A0

19

NC

5

A1

20

DQ6

6

DQ2

21

WE

7

A2

22

Vss

8

A3

23

DQ7

9

Vss

24

NC

10

DQ3

25

DQ8

11

A4

26

Q9

12

A5

27

RAS

13

DQ4

28

PCAS

14

A6

29

D9

15

A7

30

Vcc

FUNCTIONAL DIAGRAM