DESCRIPTION
Accutek
Microcircuit
Corporation
AK632256AW
262,144 x 32 Bit CMOS/BiCMOS
Static Random Access Memory
The Accutek AK632256AW SRAM Module consists of eight fast
high performance SRAMs mounted on a low profile, 64 pin SIM
PCB. The module utilizes four 28 pin 256K x 4 SRAMs in 300 mil
SOJ packages and four decoupling capacitor chips mounted on
each side of a printed circuit board.
The SRAMs used have common I/O functions and single output en-
able functions. Also, four separate chip select (CE) connections are
used to independently enable the four bytes. The modules can be
supplied in a variety of access time values from 12 nSEC to 45
nSEC in CMOS or BiCMOS technology.
The Accutek module is designed to have a maximum seated height
of 0.600 inch to provide for the lowest height off the board. By off-
set-mounting the back surface SRAMs the module can be mounted
in either angled or straight-up SIM sockets. The modules conform
to JEDEC standard sizes and pin-out configurations. Using two
pins for module memory density identification, PD
0
and PD
1
, mini-
mizes interchangeability and design considerations when changing
from one module size to another in customer applications.
Top View
64-Pin SIM
1
32
33
64
FEATURES
·
·
·
·
·
262,144 x 32 bit organization
JEDEC Standardized 64 pin SIM format
Available with solder or gold leads
Presence Detect PD
0
and PD
1
for identifying module density
Common I/O, single OE functions with four separate chip
selects (CE)
·
Low height, 0.600 inch maximum seated height
·
Single 5 volt power suppy - AK632256AW
·
Single 3.3 volt power supply - AK632256AW/3.3
·
Downward compatible with 128K x 32 (AK632128), 64K x 32
(AK63264) and 32K x 32 (AK63232)
·
Upward compatible with 512K x 32 (AK632512) and 1 Meg x 32
(AK6321024)
·
Fast access times range from 12 nSEC BiCMOS to 45 nSEC
CMOS
·
TTL-compatible inputs and outputs
·
Operating temperature range in free air, 0
0
C to 70
0
C
ELECTRICAL SPECIFICATIONS
Timing diagrams and basic electrical characteristics are those of
the standard 256K x 4 SRAMs used to construct these modules.
Accutek’s module design allows the flexibility of selecting indus-
try-compatible 256K x 4 SRAMs from several semiconductor manu-
facturers.
PIN NOMENCLATURE
A
0
- A
17
CE
1
- CE
4
DQ
1
- DQ
32
OE
PD
0
- PD
1
Vcc
Vss
WE
Address Inputs
Chip Enable
Data In/Data Out
Output Enable
Presence Detect
Power Supply
Ground
Write Enable
PIN ASSIGNMENT
PIN #
SYMBOL
PIN #
SYMBOL
PIN #
SYMBOL
PIN #
SYMBOL
FUNCTIONAL DIAGRAM
CE4
CE3
A17
A16
OE
Vss
DQ25
DQ17
DQ26
DQ18
DQ27
DQ19
DQ28
DQ20
A3
A10
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
A4
A11
A5
A12
Vcc
A13
A6
DQ21
DQ29
DQ22
DQ30
DQ23
DQ31
DQ24
DQ32
Vss
1
2
3
4
5
6
7
8
9
10
11
Vss
PD0
PD1
DQ1
DQ9
DQ2
DQ10
DQ3
DQ11
DQ4
DQ12
Vcc
A0
A7
A1
A8
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
A2
A9
DQ13
DQ5
DQ14
DQ6
DQ15
DQ7
DQ16
DQ8
Vss
WE
A15
A14
CE2
CE1
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
MODULE OPTIONS
Leadless SIM, Solder Leads: AK632256AW
Leadless SIM, Gold Leads: AK632256AWG
12
13
14
15
16
PD
0
= Vss
PD
1
= Vss
ACCUTEK [ ACCUTEK MICROCIRCUIT CORPORATION ]
