CY62148 Datasheet, PDF (1/7 Pages) Cypress Semiconductor – 512K x 8 Static RAM

1CY 621 48
fax id: 1079
PRELIMINARY
CY62148
Features
• 4.5V−5.5V operation
• CMOS for optimum speed/power
• Low active power
— 660 mW (max.)
• Low standby power (L version)
— 2.75 mW (max.)
• Automatic power-down when deselected
• TTL-compatible inputs and outputs
• Easy memory expansion with CE and OE options
Functional Description
The CY62148 is a high-performance CMOS static RAM orga-
nized as 524,288 words by 8 bits. Easy memory expansion is
provided by an active LOW chip enable (CE), an active LOW
output enable (OE), and three-state drivers. This device has
Logic Block Diagram
512K x 8 Static RAM
an automatic power-down feature that reduces power con-
sumption by more than 99% when deselected.
Writing to the device is accomplished by taking chip enable
one (CE) and write enable (WE) inputs LOW. Data on the eight
I/O pins (I/O₀ through I/O₇) is then written into the location
specified on the address pins (A₀ through A₁₈).
Reading from the device is accomplished by taking chip en-
able one (CE) and output enable (OE) LOW while forcing write
enable (WE). Under these conditions, the contents of the
memory location specified by the address pins will appear on
the I/O pins.
The eight input/output pins (I/O₀ through I/O₇) are placed in a
high-impedance state when the device is deselected (CE
HIGH), the outputs are disabled (OE HIGH), or during a write
operation (CE LOW, and WE LOW).
The CY62148 is available in a standard 450-mil-wide body
width SOIC package.
Pin Configuration
INPUT BUFFER
A₀
A₁
A₂
A₃
A₄
A₅
A₆
512K x 8
A₇
ARRAY
A₈
A₉
A₁₀
CE
COLUMN
DECODER
POWER
DOWN
WE
OE
Selection Guide
Maximum Access Time (ns)
Maximum Operating Current
Maximum CMOS Standby Current
Shaded areas contain advance information
I/O₀
I/O₁
I/O₂
I/O₃
I/O₄
I/O₅
I/O₆
62148-1
I/O₇
Top View
SOIC
A_{17 1}
A_{16 2}
A₁₄ 3
A₁₂ 4
A₇ 5
A₆ 6
A_{5 7}
A₄ 8
A₃ 9
A₂ 10
A_{1 11}
A₀ 12
I/O_{0 13}
I/O_{1 14}
I/O_{2 15}
GND ₁₆
32 VCC
31 A₁₅
30 A₁₈
29 WE
28 _A13
27 _A8
26 _A9
25 _A11
24 _OE
23 A₁₀
22 CE
21 I/O7
20 ^I/O6
19 ^I/O5
18 ^I/O4
17 I/O₃
Commercial
Commercial
CY62148–55 CY62148–70
55
70
120 mA
120 mA
2 mA
2 mA
L
0.5 mA
0.5 mA
Cypress Semiconductor Corporation • 3901 North First Street • San Jose • CA 95134 • 408-943-2600
December 1996 - Revised July 31, 1997