DESCRIPTION
The Accutek AK536256W high density memory module is a CMOS
dynamic RAM organized in 256K x 36 bit words. The module con-
sists of eight standard 256K x 4 DRAMs in plastic SOJ packages
and four 256K x 1 DRAMs in PLCC packages. The assembly has
12 drams mounted on the front side of a printed circuit board in a 72
pad leadless SIM configuration.
The operation of the AK536256W is identical to eight 256K x 4 plus
four 256K x 1 DRAMs. There are four CAS lines and two RAS lines.
Independent byte control is accomplished by four CAS lines. Each
separate CAS line controls two 256K x 4 DRAMs, along with one
256K x 1 DRAM with data in tied to data out to form a 9 bit byte. The
bank of 36 bits is controlled by the two RAS lines. An eighteen bit
data path can be produced by connecting DQ0to DQ18,DQ
1to
DQ19, etc. and alternately strobing RAS0and RAS2.
FEATURES
·262,144 x 36 bit organization
·72 pad Single In-Line Module
·Multiple CAS and RAS lines allow x18 or x36 bit widths
·CAS-before-RAS refresh
·Operating free air temperature 0oCto70
oC
·Single 5 Volt Power Supply
·Power
2.705 Watt Max Active (70nS)
2.375 Watt Max Active (80 nS)
2.045 Watt Max Active (100 nS)
66 mW Max Standby
·512 Refresh Cycles, 8 mSEC
·Available in Fast Page Mode and Static Column Mode ver-
sions
·Upward compatible with AK536512W, AK5361024W,
AK5362048W, AK5364096W and AK5368192W
Accutek
Microcircuit
Corporation
AK536256W
262,144 Word by 36 Bit CMOS
Dynamic Random Access Memory
+
+
PIN NOMENCLATURE
DQ0-DQ
35 Data In/Data Out
A0-A
8Address Inputs
CAS0- CAS3Column Address Strobe
RAS0, RAS2Row Address Strobe
WE Write Enable
PD Presence Detect
Vcc 5v Supply
Vss Ground
NC No Connect
MODULE OPTIONS
Leadless SIM: AK536256W
Leaded ZIP: AK536256Z
PIN ASSIGNMENT
PIN # SYMBOL PIN # SYMBOL PIN # SYMBOL PIN # SYMBOL
1 Vss 19 NC 37 DQ17 55 DQ12
2 DQ0 20 DQ4 38 DQ35 56 DQ30
3 DQ18 21 DQ22 39 Vss 57 DQ13
4 DQ1 22 DQ5 40 CAS0 58 DQ31
5 DQ19 23 DQ23 41 CAS2 59 Vcc
6 DQ2 24 DQ6 42 CAS3 60 DQ32
7 DQ20 25 DQ24 43 CAS1 61 DQ14
8 DQ3 26 DQ7 44 RAS0 62 DQ33
9 DQ21 27 DQ25 45 NC 63 DQ15
10 Vcc 28 A7 46 NC 64 DQ34
11 NC 29 NC 47 WE 65 DQ16
12 A0 30 Vcc 48 NC 66 NC
13 A1 31 A8 49 DQ9 67 PD1
14 A2 32 NC 50 DQ27 68 PD2
15 A3 33 NC 51 DQ10 69 PD3
16 A4 34 RAS2 52 DQ28 70 PD4
17 A5 35 DQ26 53 DQ11 71 NC
18 A6 36 DQ8 54 DQ29 72 Vss
Presence Detect -
-60 -70 -80
PD1 Vss Vss Vss
PD2 NC NC NC
PD3 NC Vss NC
PD4 NC NC Vss
FUNCTIONAL DIAGRAM
MECHANICAL DIMENSIONS
ACCUTEK MICROCIRCUIT CORPORATION
BUSINESS CENTER at NEWBURYPORT
2 NEW PASTURE ROAD, SUITE 1
NEWBURYPORT, MA 01950-4054
PHONE: 978-465-6200 FAX: 978-462-3396
E-Mail: sales@accutekmicro.com
Internet: www.accutekmicro.com
Accutek reserves the right to make changes in specifications at any time and without notice.
Accutek does not assume any responsibility for the use of any circuitry described; no circuit
patent licenses are implied. Preliminary data sheets contain minimum and maximum limits
based upon design objectives, which are subject to change upon full characterization over
the specific operating conditions.
C
LC
L
C
L
+
+
4.240"
4.260"
1.000"
MAX
0.200"
MAX
0.425"
0.375" 0.250"
C
L
0.080"
3.979"
3.989"
0.125" 0.050"
TYP
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
DQ1
DQ2
DQ3
DQ4
RAS
CAS
WE
OE
A0 - A8
RAS
CAS
WE
A0 - A8
RAS
CAS
WE
A0 - A8
RAS
CAS
WE
A0 - A8
RAS
CAS
WE
D
Q
D
Q
D
Q
D
Q
DQ0
DQ1
DQ2
DQ3
DQ18
DQ19
DQ20
DQ21
DQ9
DQ10
DQ11
DQ12
DQ27
DQ28
DQ29
DQ30
DQ4
DQ5
DQ6
DQ7
DQ22
DQ23
DQ24
DQ25
DQ13
DQ14
DQ15
DQ16
DQ31
DQ32
DQ33
DQ34
DQ8 DQ26
DQ17 DQ35
CAS
RAS
0
0
CAS
RAS
2
2
CAS1 CAS3
A0
A1
A2
A3
A4
A5
A6
A7
A8
WE
