Cypress manual Pin Definitions, CY7C1381DV25, CY7C1381FV25 CY7C1383DV25, CY7C1383FV25, Name

CY7C1381DV25, CY7C1381FV25

CY7C1383DV25, CY7C1383FV25

Pin Definitions

Name

IO

Description

A0, A1, A

Input-

Address inputs used to select one of the address locations. Sampled at the rising edge

Synchronous

of the CLK if ADSP or

ADSC

is active LOW, and CE

1

, CE

2

, and CE [2] are sampled active.

A[1:0] feed the 2-bit counter.

3

A,

B

Input-

Byte write select inputs, active LOW. Qualified with

to conduct byte writes to the

BW

BW

BWE

BWC, BWD

Synchronous

SRAM. Sampled on the rising edge of CLK.

Input-

Global write enable input, active LOW. When asserted LOW on the rising edge of CLK, a

GW

Synchronous

global write is conducted (all bytes are written, regardless of the values on BW[A:D] and BWE).

CLK

Input-

Clock input. Used to capture all synchronous inputs to the device. Also used to increment

Clock

the burst counter when ADV is asserted LOW, during a burst operation.

1

Input-

Chip enable 1 input, active LOW. Sampled on the rising edge of CLK. Used in conjunction

CE

Synchronous

with CE2 and

3 [2] to select or deselect the device. ADSP is ignored if CE1 is HIGH. CE1

CE

is sampled only when a new external address is loaded.

CE2

Input-

Chip enable 2 input, active HIGH. Sampled on the rising edge of CLK. Used in conjunction

Synchronous

with CE

and

[2] to select or deselect the device. CE

is sampled only when a new

1

CE

3

2

external address is loaded.

3 [2]

Input-

Chip enable 3 input, active LOW. Sampled on the rising edge of CLK. Used in conjunction

CE

Synchronous

with CE1 and CE2 to select or deselect the device. CE3 is sampled only when a new external

address is loaded.

Input-

Output enable, asynchronous input, active LOW. Controls the direction of the IO pins.

OE

Asynchronous

When LOW, the IO pins behave as outputs. When deasserted HIGH, IO pins are tri-stated,

and act as input data pins. OE is masked during the first clock of a read cycle when emerging

from a deselected state.

Input-

Advance input signal. Sampled on the rising edge of CLK. When asserted, it automatically

ADV

Synchronous

increments the address in a burst cycle.

Input-

Address strobe from processor, sampled on the rising edge of CLK, active LOW. When

ADSP

Synchronous

asserted LOW, addresses presented to the device are captured in the address registers.

A[1:0] are also loaded into the burst counter. When ADSP and ADSC are both asserted, only

ADSP is recognized. ASDP is ignored when CE1 is deasserted HIGH.

Input-

Address strobe from controller, sampled on the rising edge of CLK, active LOW. When

ADSC

Synchronous

asserted LOW, addresses presented to the device are captured in the address registers.

A[1:0] are also loaded into the burst counter. When ADSP and ADSC are both asserted, only

ADSP is recognized.

Input-

Byte write enable input, active LOW. Sampled on the rising edge of CLK. This signal must

BWE

Synchronous

be asserted LOW to conduct a byte write.

ZZ

Input-

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

Asynchronous

condition with data integrity preserved. For normal operation, this pin has to be LOW or left

floating. ZZ pin has an internal pull down.

DQs

IO-

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

Synchronous

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

specified by the addresses presented during the previous clock rise of the read cycle. The

direction of the pins is controlled by OE. When OE is asserted LOW, the pins behave as

outputs. When HIGH, DQs and DQPX 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.

DQPX

IO-

Bidirectional data parity IO lines. Functionally, these signals are identical to DQs. During

Synchronous

write sequences, DQPX is controlled by BWX correspondingly.

Document #: 38-05547 Rev. *E

Page 6 of 28

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