Cypress CY7C1360C, CY7C1362C manual Interleaved Burst Address Table Mode = Floating or VDD

Models: CY7C1362C CY7C1360C

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CY7C1360C

CY7C1362C

conducted, the data presented to the DQs is written into the corresponding address location in the memory core. If a Byte Write is conducted, only the selected bytes are written. Bytes not selected during a Byte Write operation will remain unaltered. A synchronous self-timed Write mechanism has been provided to simplify the Write operations.

Because the CY7C1360C/CY7C1362C is a common I/O device, the Output Enable (OE) must be deasserted HIGH before presenting data to the DQs inputs. Doing so will tri-state the output drivers. As a safety precaution, DQs are automati- cally tri-stated whenever a Write cycle is detected, regardless of the state of OE.

Burst Sequences

The CY7C1360C/CY7C1362C provides a two-bit wraparound counter, fed by A1, A0, that implements either an interleaved or linear burst sequence. The interleaved burst sequence is designed specifically to support Intel Pentium applications. The linear burst sequence is designed to support processors that follow a linear burst sequence. The burst sequence is user selectable through the MODE input.

Asserting ADV LOW at clock rise will automatically increment the burst counter to the next address in the burst sequence. Both Read and Write burst operations are supported.

Sleep Mode

The ZZ input pin is an asynchronous input. Asserting ZZ places the SRAM in a power conservation “sleep” mode. Two

clock cycles are required to enter into or exit from this “sleep” mode. While in this mode, data integrity is guaranteed. Accesses pending when entering the “sleep” mode are not considered valid nor is the completion of the operation guaranteed. The device must be deselected prior to entering the “sleep” mode. CE1, CE2, CE3[2], ADSP, and ADSC must remain inactive for the duration of tZZREC after the ZZ input returns LOW.

Interleaved Burst Address Table (MODE = Floating or VDD)

First

Second

Third

Fourth

Address

Address

Address

Address

A1, A0

A1, A0

A1, A0

A1, A0

00

01

10

11

01

00

11

10

10

11

00

01

11

10

01

00

Linear Burst Address Table (MODE = GND)

First

Second

Third

Fourth

Address

Address

Address

Address

A1, A0

A1, A0

A1, A0

A1, A0

00

01

10

11

01

10

11

00

10

11

00

01

11

00

01

10

ZZ Mode Electrical Characteristics

Parameter

 

Description

 

 

 

 

 

 

 

Test Conditions

 

 

 

 

Min.

 

 

 

Max.

Unit

IDDZZ

 

Sleep mode standby current

 

 

 

 

 

ZZ > VDD – 0.2V

 

 

 

 

 

 

 

 

 

50

 

mA

tZZS

 

Device operation to ZZ

 

 

 

 

 

 

 

ZZ > VDD – 0.2V

 

 

 

 

 

 

 

 

 

 

2tCYC

ns

tZZREC

 

ZZ recovery time

 

 

 

 

 

 

 

ZZ < 0.2V

 

 

 

 

 

 

 

2tCYC

 

 

 

 

 

ns

tZZI

 

ZZ Active to sleep current

 

 

 

 

 

 

 

This parameter is sampled

 

 

 

 

 

 

 

 

 

2tCYC

ns

tRZZI

 

ZZ Inactive to exit sleep current

 

 

 

 

 

This parameter is sampled

 

 

0

 

 

 

 

 

 

 

ns

Truth Table[3, 4, 5, 6, 7, 8]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Address

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Operation

Used

 

CE

1

CE2

 

CE

3

 

ZZ

 

ADSP

 

 

ADSC

 

 

ADV

 

 

 

WRITE

 

 

OE

 

CLK

 

DQ

Deselect Cycle, Power Down

None

 

H

X

 

X

 

L

 

X

 

L

 

X

 

 

 

X

 

X

 

L-H

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Deselect Cycle, Power Down

None

 

L

L

 

X

 

L

 

L

 

X

 

X

 

 

 

X

 

X

 

L-H

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Deselect Cycle, Power Down

None

 

L

X

 

H

 

L

 

L

 

X

 

X

 

 

 

X

 

X

 

L-H

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Deselect Cycle, Power Down

None

 

L

L

 

X

 

L

 

H

 

L

 

X

 

 

 

X

 

X

 

L-H

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Deselect Cycle, Power Down

None

 

L

X

 

H

 

L

 

H

 

L

 

X

 

 

 

X

 

X

 

L-H

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sleep Mode, Power Down

None

 

X

X

 

X

 

H

 

X

 

X

 

X

 

 

 

X

 

X

 

X

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

READ Cycle, Begin Burst

External

 

L

H

 

L

 

L

 

L

 

X

 

X

 

 

 

X

 

L

 

L-H

 

Q

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

READ Cycle, Begin Burst

External

 

L

H

 

L

 

L

 

L

 

X

 

X

 

 

 

X

 

H

 

L-H

 

Tri-State

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

WRITE Cycle, Begin Burst

External

 

L

H

 

L

 

L

 

H

 

L

 

X

 

 

 

L

 

X

 

L-H

 

D

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Notes:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.X = “Don't Care.” H = Logic HIGH, L = Logic LOW.

4.WRITE = L when any one or more Byte Write Enable signals and BWE = L or GW = L. WRITE = H when all Byte Write Enable signals, BWE, GW = H.

5.The DQ pins are controlled by the current cycle and the OE signal. OE is asynchronous and is not sampled with the clock.

6.CE1, CE2, and CE3 are available only in the TQFP package. BGA package has only two chip selects CE1 and CE2.

7.The SRAM always initiates a read cycle when ADSP is asserted, regardless of the state of GW, BWE, or BWX. Writes may occur only on subsequent clocks after the ADSP or with the assertion of ADSC. As a result, OE must be driven HIGH prior to the start of the Write cycle to allow the outputs to tri-state. OE is a don't care for the remainder of the Write cycle.

8.OE is asynchronous and is not sampled with the clock rise. It is masked internally during Write cycles. During a Read cycle all data bits are Tri-State when OE is inactive or when the device is deselected, and all data bits behave as output when OE is active (LOW).

Document #: 38-05540 Rev. *H

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Cypress CY7C1360C, CY7C1362C Interleaved Burst Address Table Mode = Floating or VDD, Linear Burst Address Table Mode = GND