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Sram read cycle, Ac switching characteristics, Switching waveforms – Cypress CY14E256L User Manual

Page 9

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CY14E256L

Document Number: 001-06968 Rev. *F

Page 9 of 18

AC Switching Characteristics

SRAM Read Cycle

Parameter

Description

25 ns

35 ns

45 ns

Unit

Min

Max

Min

Max

Min

Max

Cypress

Parameter

Alt

t

ACE

t

ELQV

Chip Enable Access Time

25

35

45

ns

t

RC

[9]

t

AVAV,

t

ELEH

Read Cycle Time

25

35

45

ns

t

AA

[10]

t

AVQV

Address Access Time

25

35

45

ns

t

DOE

t

GLQV

Output Enable to Data Valid

10

15

20

ns

t

OHA

[10]

t

AXQX

Output Hold After Address Change

5

5

5

ns

t

LZCE

[11]

t

ELQX

Chip Enable to Output Active

5

5

5

ns

t

HZCE

[11]

t

EHQZ

Chip Disable to Output Inactive

10

13

15

ns

t

LZOE

[11]

t

GLQX

Output Enable to Output Active

0

0

0

ns

t

HZOE

[11]

t

GHQZ

Output Disable to Output Inactive

10

13

15

ns

t

PU

[8]

t

ELICCH

Chip Enable to Power Active

0

0

0

ns

t

PD

[8]

t

EHICCL

Chip Disable to Power Standby

25

35

45

ns

Switching Waveforms

Figure 7. SRAM Read Cycle 1: Address Controlled

[9, 10]

Figure 8. SRAM Read Cycle 2: CE and OE Controlled

[9]

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Notes

9. WE and HSB must be HIGH during SRAM Read cycles.
10. Device is continuously selected with CE and OE both Low.
11. Measured ±200 mV from steady state output voltage.

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