Cypress CY7C185 specifications Features, Functional Description, Selection Guide1

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CY7C185

Features

High speed

15 ns

Fast t DOE

Low active power

715 mW

Low standby power

220 mW

CMOS for optimum speed/power

Easy memory expansion with CE1, CE2, and OE features

TTL-compatible inputs and outputs

Automatic power-down when deselected

Functional Description

The CY7C185 is a high-performance CMOS static RAM orga- nized as 8192 words by 8 bits. Easy memory expansion is

8K x 8 Static RAM

provided by an active LOW chip enable (CE1), an active HIGH chip enable (CE2), and active LOW output enable (OE) and three-state drivers. This device has an automatic power-down feature (CE1 or CE2), reducing the power consumption by 70% when deselected. The CY7C185 is in a standard 300-mil-wide DIP, SOJ, or SOIC package.

An active LOW write enable signal (WE) controls the writ- ing/reading operation of the memory. When CE1 and WE in- puts are both LOW and CE2 is HIGH, data on the eight data input/output pins (I/O0 through I/O7) is written into the memory location addressed by the address present on the address pins (A0 through A12). Reading the device is accomplished by

selecting the device and enabling the outputs, CE1 and OE active LOW, CE2 active HIGH, while WE remains inactive or HIGH. Under these conditions, the contents of the location ad- dressed 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. A die coat is used to insure alpha immunity.

Logic Block Diagram

Pin Configurations

 

 

 

 

 

 

 

I/O0

 

INPUT BUFFER

 

I/O1

 

 

 

 

 

 

 

A1

ROW DECODER

 

 

 

 

SENSE AMPS

I/O2

A2

 

 

 

 

 

A3

 

 

 

 

I/O3

A4

256 x 32 x 8

 

 

A5

ARRAY

 

I/O4

A6

 

 

 

 

A7

 

 

 

 

I/O5

A

 

 

 

 

 

 

8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I/O6

CE1

 

 

 

 

 

POWER

I/O7

COLUMN DECODER

DOWN

CE2

WE

 

 

 

 

 

 

 

OE

 

 

 

 

 

 

 

 

0

9

10

11

12

 

C185–1

 

A

A

A

A

A

 

 

 

 

DIP/SOJ/SOIC

Top View

NC

1

28

VCC

A4

2

27

WE

A5

3

26

CE2

A6

4

25

A3

A7

5

24

A2

A8

6

23

A1

A9

7

22

OE

A10

8

21

A0

A11

9

20

CE1

A12

10

19

I/O7

I/O0

11

18

I/O6

I/O1

12

17

I/O5

I/O2

13

16

I/O4

GND

14

15

I/O3

C185–2

Selection Guide[1]

 

7C185–15

7C185–20

7C185–25

7C185–35

 

 

 

 

 

Maximum Access Time (ns)

15

20

25

35

 

 

 

 

 

Maximum Operating Current (mA)

130

110

100

100

 

 

 

 

 

Maximum Standby Current (mA)

40/15

20/15

20/15

20/15

 

 

 

 

 

Note:

 

 

 

 

1.For military specifications, see the CY7C185A datasheet.

Cypress Semiconductor Corporation • 3901 North First Street • San Jose • CA 95134 • 408-943-2600 August 12, 1998

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Contents Logic Block Diagram Pin Configurations FeaturesFunctional Description Selection Guide1Maximum Ratings Electrical Characteristics Over the Operating RangeOperating Range Ambient RangeAC Test Loads and Waveforms Capacitance4= GND Parameter Description Test Conditions Max UnitCE2 Switching Characteristics Over the Operating Range5Read Cycle No.19,10 Switching WaveformsWrite Cycle No WE Controlled10,12 Write Cycle No WE Controlled, OE LOW12,13,14,15 Write Cycle No CE Controlled12,13,14Normalized Supply Current Typical DC and AC CharacteristicsAddress Designators Truth TableOrdering Information Lead 300-Mil Molded DIP P21 Package DiagramsLead 300-Mil Molded Soic S21 Lead 300-Mil Molded SOJ