CY62256
256K (32K x 8) Static RAM
Features
• High speed
— 55 ns
• Temperature Ranges
— Commercial: 0°C to 70°C
— Industrial: –40°C to 85°C
— Automotive: –40°C to 125°C
• Voltage range
— 4.5V – 5.5V
• Low active power and standby power
• Easy memory expansion with CE and OE features
• TTL-compatible inputs and outputs
• Automatic power-down when deselected
• CMOS for optimum speed/power
• Available in a Pb-free and non Pb-free standard 28-pin
narrow SOIC, 28-pin TSOP-1, 28-pin Reverse TSOP-1
and 28-pin DIP packages
Functional Description
[1]
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 Tri-state drivers. This device has an
automatic power-down feature, reducing the power
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
0
through I/O
7
) is written into the memory location
addressed by the address present on the address pins (A
0
through A
14
). Reading the device is accomplished by selecting
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.
Logic Block Diagram
INPUTBUFFER
A
10
A
9
A
8
A
7
A
6
A
5
A
4
A
3
A
2
CE
WE
OE
A
14
A
13
A
12
A
11
A
1
A
0
ROW DECODER
I/O
0
I/O
1
SENSE AMPS
I/O
2
I/O
3
I/O
4
I/O
5
32K × 8
ARRAY
COLUMN
DECODER
POWER
DOWN
I/O
6
I/O
7
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. *F
•
198 Champion Court
•
San Jose
,
CA 95134-1709
•
408-943-2600
Revised August 3, 2006
CYPRESS [ CYPRESS SEMICONDUCTOR ]
