コンピュータ・ハードウェア Cypress CY62256のPDF 仕様書をオンラインで閲覧またはダウンロードできます。Cypress CY62256 11 ページ。 256k (32k x 8) static ram
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Features
• High speed: 55 ns and 70 ns
• Voltage range: 4.5V–5.5V operation
• Low active power (70 ns, LL version)
— 275 mW (max.)
• Low standby power (70 ns, LL version)
— 28 W (max.)
• Easy memory expansion with CE and OE features
• TTL-compatible inputs and outputs
• Automatic power-down when deselected
• CMOS for optimum speed/power
• Package available in a standard 450-mil-wide (300-mil
body width) 28-lead narrow SOIC, 28-lead TSOP-1,
28-lead reverse TSOP-1, and 600-mil 28-lead PDIP
packages
Logic Block Diagram
Note:
1.
For best practice recommendations, please refer to the Cypress application note "System Design Guidelines" on http://www.cypress.com.
Cypress Semiconductor Corporation
Document #: 38-05248 Rev. *B
INPUTBUFFER
A
10
A
9
A
8
A
7
A
6
512 x 512
A
5
ARRA Y
A
4
A
3
A
2
CE
WE
COLUMN
DECODER
OE
•
3901 North First Street
256K (32K x 8) Static RAM
Functional Description
The CY62256 is a high-performance CMOS static RAM
organized as 32K words by 8 bits. Easy memory expansion is
provided by an active LOW chip enable (CE) and active LOW
output enable (OE) and three-state drivers. This device has an
automatic
power-down
consumption by 99.9% when deselected.
An active LOW write enable signal (WE) controls the
writing/reading operation of the memory. When CE and WE
inputs are both LOW, data on the eight data input/output pins
(I/O
through I/O
) is written into the memory location
0
7
addressed by the address present on the address pins (A
through A
). Reading the device is accomplished by selecting
14
the device and enabling the outputs, CE and OE active LOW,
while WE remains inactive or HIGH. Under these conditions,
the contents of the location addressed by the information on
address pins are present on the eight data input/output pins.
The input/output pins remain in a high-impedance state unless
the chip is selected, outputs are enabled, and write enable
(WE) is HIGH.
POWER
DOWN
•
San Jose
•
CY62256
[1]
feature,
reducing
the
I/O
0
I/O
1
I/O
2
I/O
3
I/O
4
I/O
5
I/O
6
I/O
7
CA 95134
•
408-943-2600
Revised August 27, 2002
power
0