Pin definitions – Cypress CY7C1353G User Manual

Page 3

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CY7C1353G

Document #: 38-05515 Rev. *E

Page 3 of 13

Pin Definitions

Name

IO

Description

A

0

, A

1

, A

Input-

Synchronous

Address Inputs used to select one of the 256K address locations. Sampled at the rising edge

of the CLK. A

[1:0]

are fed to the two-bit burst counter.

BW

[A:B]

Input-

Synchronous

Byte Write Inputs, Active LOW. Qualified with WE to conduct writes to the SRAM. Sampled on

the rising edge of CLK.

WE

Input-

Synchronous

Write Enable Input, Active LOW. Sampled on the rising edge of CLK if CEN is active LOW. This

signal must be asserted LOW to initiate a write sequence.

ADV/LD

Input-

Synchronous

Advance/Load Input. Used to advance the on-chip address counter or load a new address. When

HIGH (and CEN is asserted LOW) the internal burst counter is advanced. When LOW, a new

address can be loaded into the device for an access. After being deselected, ADV/LD must be

driven LOW to load a new address.

CLK

Input-Clock

Clock Input. Used to capture all synchronous inputs to the device. CLK is qualified with CEN. CLK

is only recognized if CEN is active LOW.

CE

1

Input-

Synchronous

Chip Enable 1 Input, Active LOW. Sampled on the rising edge of CLK. Used in conjunction with

CE

2

, and CE

3

to select/deselect the device.

CE

2

Input-

Synchronous

Chip Enable 2 Input, Active HIGH. Sampled on the rising edge of CLK. Used in conjunction with

CE

1

and CE

3

to select/deselect the device.

CE

3

Input-

Synchronous

Chip Enable 3 Input, Active LOW. Sampled on the rising edge of CLK. Used in conjunction with

CE

1

and

CE

2

to select/deselect the device.

OE

Input-

Asynchronous

Output Enable, asynchronous input, Active LOW. Combined with the synchronous logic block

inside the device to control the direction of the IO pins. When LOW, the IO pins are allowed to

behave as outputs. When deasserted HIGH, IO pins are tri-stated, and act as input data pins. OE

is masked during the data portion of a write sequence, during the first clock when emerging from

a deselected state, when the device has been deselected.

CEN

Input-

Synchronous

Clock Enable Input, Active LOW. When asserted LOW the Clock signal is recognized by the

SRAM. When deasserted HIGH the Clock signal is masked. While deasserting CEN does not

deselect the device, CEN can be used to extend the previous cycle when required.

ZZ

Input-

Asynchronous

ZZ “sleep” Input. This active HIGH input places the device in a non-time critical “sleep” condition

with data integrity preserved. During normal operation, this pin has to be low or left floating. ZZ pin

has an internal pull down.

DQ

s

IO-

Synchronous

Bidirectional Data IO Lines. As inputs, they feed into an on-chip data register that is triggered by

the rising edge of CLK. As outputs, they deliver the data contained in the memory location specified

by address during the clock rise of the read cycle. The direction of the pins is controlled by OE and

the internal control logic. When OE is asserted LOW, the pins can behave as outputs. When HIGH,

DQ

s

and DQP

[A:B]

are placed in a tri-state condition. The outputs are automatically tri-stated during

the data portion of a write sequence, during the first clock when emerging from a deselected state,

and when the device is deselected, regardless of the state of OE.

DQP

[A:B]

IO-

Synchronous

Bidirectional Data Parity IO Lines. Functionally, these signals are identical to DQ

s

. During write

sequences, DQP

[A:B]

is controlled by BW

x

correspondingly.

MODE

Input

Strap Pin

MODE Input. Selects the burst order of the device.

When tied to Gnd selects linear burst sequence. When tied to V

DD

or left floating selects interleaved

burst sequence.

V

DD

Power Supply Power supply inputs to the core of the device.

V

DDQ

IO Power

Supply

Power supply for the IO circuitry.

V

SS

Ground

Ground for the device.

NC,NC/9M,

NC/18M,

NC/36M

NC/72M,

NC/144M,

NC/288M,

No Connects. Not internally connected to the die. NC/9M, NC/18M, NC/72M, NC/144M, NC/288M,

are address expansion pins are not internally connected to the die.

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