CY7C1334H

 

Pin Definitions

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Name

 

I/O

 

Description

 

 

 

 

 

 

 

 

 

A0, A1, A

 

Input-

 

Address Inputs used to select one of the 64K address locations. Sampled at the rising edge

 

 

 

 

 

 

 

 

 

 

Synchronous

 

of the CLK. A[1:0] are fed to the two-bit burst counter.

 

 

 

 

 

[A:D]

 

Input-

 

Byte Write Inputs, active LOW. Qualified with

 

to conduct writes to the SRAM. Sampled

 

 

BW

WE

 

 

 

 

 

 

 

 

 

 

Synchronous

 

on the rising edge of CLK.

 

 

 

 

 

 

 

 

 

 

Input-

 

Write Enable Input, active LOW. Sampled on the rising edge of CLK if

 

is active LOW.

 

 

WE

CEN

 

 

 

 

 

 

 

 

 

 

Synchronous

 

This signal must be asserted LOW to initiate a Write sequence.

 

 

 

 

 

 

 

 

 

 

Input-

 

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

 

 

ADV/LD

 

 

 

 

 

 

 

 

 

 

 

 

 

Synchronous

 

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

 

 

 

 

 

 

 

 

 

 

 

 

 

should be driven LOW in order 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.

 

 

 

1

 

 

Input-

 

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

 

 

CE

 

 

 

 

 

 

 

 

 

 

Synchronous

 

with CE2 and CE3 to select/deselect the device.

 

 

CE2

 

Input-

 

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

 

 

 

 

 

 

 

 

 

 

Synchronous

 

with CE1 and CE3 to select/deselect the device.

 

 

 

3

 

 

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/deselect the device.

 

 

 

 

 

 

 

Input-

 

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

 

 

OE

 

 

 

 

 

 

 

 

 

 

Asynchronous

 

block inside the device to control the direction of the I/O pins. When LOW, the I/O pins are

 

 

 

 

 

 

 

 

 

 

 

 

 

allowed to behave as outputs. When deasserted HIGH, I/O 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.

 

 

 

 

 

 

 

 

Input-

 

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

 

 

CEN

 

 

 

 

 

 

 

 

 

 

Synchronous

 

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

 

 

 

 

 

 

 

 

 

 

 

 

 

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

 

 

ZZ

 

Input-

 

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

 

 

 

 

 

 

 

 

 

 

Asynchronous

 

condition with data integrity preserved. During normal operation, this pin can be connected to

 

 

 

 

 

 

 

 

 

 

 

 

 

VSS or left floating.

 

 

DQs

 

I/O-

 

Bidirectional Data I/O 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 A[16:0] 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, DQs 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.

 

 

MODE

 

Input

 

Mode Input. Selects the burst order of the device.

 

 

 

 

 

 

 

 

 

 

Strap pin

 

When tied to Gnd selects linear burst sequence. When tied to VDD or left floating selects inter-

 

 

 

 

 

 

 

 

 

 

 

 

 

leaved burst sequence.

 

 

VDD

 

Power Supply

 

Power supply inputs to the core of the device.

 

 

VDDQ

 

I/O Power

 

Power supply for the I/O circuitry.

 

 

 

 

 

 

 

 

 

 

Supply

 

 

 

 

 

 

 

 

 

 

VSS

 

Ground

 

Ground for the device.

 

 

VSSQ

 

I/O Ground

 

Ground for the I/O circuitry. Should be connected to the ground of the system

 

 

NC

 

 

 

 

No Connects. Not internally connected to the die. 4M, 9M,18M, 72M, 144M, 288M, 576M and

 

 

 

 

 

 

 

 

 

 

 

 

 

1G are address expansion pins and are not internally connected to the die.

 

Document #: 38-05678 Rev. *B

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Cypress CY7C1334H manual Pin Definitions