Dear customers,
About the change in the name such as "Oki Electric Industry Co. Ltd." and
"OKI" in documents to OKI Semiconductor Co., Ltd.
The semiconductor business of Oki Electric Industry Co., Ltd. was succeeded to OKI
Semiconductor Co., Ltd. on October 1, 2008.
Therefore, please accept that although
the terms and marks of "Oki Electric Industry Co., Ltd.", “Oki Electric”, and "OKI"
remain in the documents, they all have been changed to "OKI Semiconductor Co., Ltd.".
It is a change of the company name, the company trademark, and the logo, etc. , and
NOT a content change in documents.
October 1, 2008
OKI Semiconductor Co., Ltd.
550-1 Higashiasakawa-cho, Hachioji-shi, Tokyo 193-8550, Japan
http://www.okisemi.com/en/
E2G0057-17-41
¡ Semiconductor
MSM51V4256A
¡ Semiconductor
This version: Jan. 1998
MSM51V4256A
Previous version: May 1997
262,144-Word
¥
4-Bit DYNAMIC RAM : FAST PAGE MODE TYPE
DESCRIPTION
The MSM51V4256A is a 262,144-word
¥
4-bit dynamic RAM fabricated in Oki's silicon-gate CMOS
technology. The MSM51V4256A achieves high integration, high-speed operation, and low-power
consumption because Oki manufactures the device in a quadruple-layer polysilicon/single-layer
metal CMOS process. The MSM51V4256A is available in a 20-pin plastic DIP, 26/20-pin plastic SOJ,
or 20-pin plastic ZIP.
FEATURES
• 262,144-word
¥
4-bit configuration
• Single 3.3 V power supply, 0.3 V tolerance
• Input
: LVTTL compatible, low input capacitance
• Output : LVTTL compatible, 3-state
• Refresh : 512 cycles/8 ms
• Fast page mode, read modify write capability
•
CAS
before
RAS
refresh, hidden refresh,
RAS-only
refresh capability
• Package options:
20-pin 300 mil plastic DIP
(DIP20-P-300-2.54-W1) (Product : MSM51V4256A-xxRS)
26/20-pin 300 mil plastic SOJ (SOJ26/20-P-300-1.27) (Product : MSM51V4256A-xxJS)
20-pin 400 mil plastic ZIP
(ZIP20-P-400-1.27)
(Product : MSM51V4256A-xxZS)
xx indicates speed rank.
PRODUCT FAMILY
Family
MSM51V4256A-70
MSM51V4256A-80
MSM51V4256A-10
Access Time (Max.)
t
RAC
t
AA
t
CAC
t
OEA
70 ns 40 ns 25 ns 25 ns
80 ns 45 ns 25 ns 25 ns
100 ns 50 ns 30 ns 30 ns
Cycle Time
Power Dissipation
(Min.)
Operating (Max.) Standby (Max.)
130 ns
150 ns
190 ns
162 mW
144 mW
126 mW
1.8 mW
1/17
¡ Semiconductor
PIN CONFIGURATION (TOP VIEW)
DQ1 1
DQ2 2
WE
3
RAS
4
NC 5
A0 6
A1 7
A2 8
A3 9
V
CC
10
20 V
SS
DQ1 1
19 DQ4
18 DQ3
17
CAS
16
OE
15 A8
14 A7
13 A6
12 A5
11 A4
DQ2 2
WE
3
NC 5
A0 9
RAS
4
A1 10
A2 11
A3 12
V
CC
13
Pin Name
A0 - A8
RAS
CAS
DQ1 - DQ4
OE
WE
V
CC
V
SS
NC
MSM51V4256A
26 V
SS
25 DQ4
24 DQ3
23
CAS
22
OE
18 A8
17 A7
16 A6
15 A5
14 A4
OE
1
DQ3 3
V
SS
5
DQ2 7
RAS
9
A0 11
A2 13
V
CC
15
A5 17
A7 19
2
CAS
4 DQ4
6 DQ1
8
WE
NO LEAD
12 A1
14 A3
16 A4
18 A6
20 A8
20-Pin Plastic ZIP
26/20-Pin Plastic SOJ
20-Pin Plastic DIP
Function
Address Input
Row Address Strobe
Column Address Strobe
Data Input/Data Output
Output Enable
Write Enable
Power Supply (3.3 V)
Ground (0 V)
No Connection
2/17
¡ Semiconductor
MSM51V4256A
BLOCK DIAGRAM
RAS
CAS
Timing
Generator
Timing
Generator
9
Column
Address
Buffers
Internal
Address
Counter
9
Column
Decoders
Write
Clock
Generator
WE
OE
4
Output
Buffers
4
4
A0 - A8
Refresh
Control Clock
Sense
Amplifiers
4
I/O
Selector
4
4
DQ1 - DQ4
Input
Buffers
4
9
Row
Address
Buffers
9
Row
De-
coders
Word
Drivers
Memory
Cells
V
CC
On Chip
V
BB
Generator
V
SS
3/17
¡ Semiconductor
MSM51V4256A
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings
Parameter
Voltage on Any Pin Relative to V
SS
Short Circuit Output Current
Power Dissipation
Operating Temperature
Storage Temperature
Symbol
V
T
I
OS
P
D
*
T
opr
T
stg
Rating
–0.5 to 4.6
50
1
0 to 70
–55 to 150
Unit
V
mA
W
°C
°C
*: Ta = 25°C
Recommended Operating Conditions
Parameter
Power Supply Voltage
Input High Voltage
Input Low Voltage
Symbol
V
CC
V
SS
V
IH
V
IL
Min.
3.0
0
2.0
–0.3
Typ.
3.3
0
—
—
Max.
3.6
0
V
CC
+ 0.3
0.8
(Ta = 0°C to 70°C)
Unit
V
V
V
V
Capacitance
Parameter
Input Capacitance (A0 - A8)
Input Capacitance (RAS,
CAS, WE, OE)
Output Capacitance (DQ1 - DQ4)
Symbol
C
IN1
C
IN2
C
I/O
Typ.
—
—
—
(V
CC
= 3.3 V ±0.3 V, Ta = 25°C, f = 1 MHz)
Max.
5
5
6
Unit
pF
pF
pF
4/17