AK48256S Datasheet, PDF (1/2 Pages) ACCUTEK MICROCIRCUIT CORPORATION – 262,144 X 8 Bit MOS Dynamic Random Access Memory

Accutek
Microcircuit
Corporation
DESCRIPTION
The Accutek AK48256 high density memory modules is a random
access memory organized in 256K x 8 bit words. The assembly
consists of eight standard 256K x 1 DRAMs in plastic leaded chip
carriers (PLCC) 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 AK48256 is identical to eight 256K x 1 DRAMs.
The data input is tied to the data output and brought out separately
for each device, with common RAS, CAS and WE 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 al-
ways go low before CAS in a write cycle, Read-Write and
Read-Modify-Write operation is not possible.
FEATURES
· 262,144 by 8 bit organization
· Optional 30 Pad leadless SIM (Single In-Line Module) or 30
Pin leaded SIP (Single In-Line Package)
· JEDEC standard pinout
· Each device has common D and Q lines with common RAS,
CAS and WE control
· 2.8 Watt active and 180 mW standby (max)
· Operating free air temperature 0⁰C to 70⁰C
· Upward compatible with AK481024, AK581024, AK584096 and
AK5816384
· Functionally and Pin compatible with AK58256A
AK48256S / AK48256G
262,144 X 8 Bit MOS
Dynamic Random Access Memory
Front View
30-Pin SIM
1
30
30-Pin SIP
1
PIN NOMENCLATURE
PIN ASSIGNMENT
FUNCTIONAL DIAGRAM
A0 - A8
DQ1 - DQ8
Address Inputs
Data In / Data Out
PIN #
1
2
SYMBOL
Vcc
CAS
PIN #
16
17
SYMBOL
DQ5
A8
CAS
RAS
WE
Column Address Strobe ³
4
Row Address Strobe
5
Write Enable
6
DQ!
18
NC
A0
19
NC
A1
20
DQ6
DQ2
21
WE
Vcc
5v Supply
Vss
Ground
NC
No Connect
7
A2
22
Vss
8
A3
23
DQ7
9
Vss
24
NC
10
DQ3
25
DQ8
11
A4
26
NC
MODULE OPTIONS
12
A5
27
RAS
13
DQ4
28
NC
Leadless SIM: AK48256S
Leaded SIP: AK48256G
14
A6
29
NC
15
A7
30
Vcc