Cypress CY14B256K Manual De Usuario

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CY14B256K
Document Number: 001-06431  Rev. *H
Page 17 of 28
AC Switching Characteristics 
Parameter
Description
25 ns
35 ns
45 ns
Unit
Min
Max
Min
Max
Min
Max
Cypress
Parameter
Alt.
Parameter
SRAM Read Cycle
t
ACE
t
ELQV
Chip Enable Access Time
25
35
45
ns
t
RC 
t
AVAV, 
t
ELEH
Read Cycle Time
25
35
45
ns
t
AA 
t
AVQV
Address Access Time
25
35
45
ns
t
DOE
t
GLQV
Output Enable to Data Valid
12
15
20
ns
t
OHA 
t
AXQX
Output Hold After Address Change
3
3
3
ns
t
LZCE 
t
ELQX
Chip Enable to Output Active
3
3
3
ns
t
HZCE 
t
EHQZ
Chip Disable to Output Inactive
10
13
15
ns
t
LZOE 
t
GLQX
Output Enable to Output Active
0
0
0
ns
t
HZOE 
t
GHQZ
Output Disable to Output Inactive
10
13
15
ns
t
PU 
t
ELICCH
Chip Enable to Power Active
0
0
0
ns
t
PD 
t
EHICCL
Chip Disable to Power Standby
25
35
45
ns
Figure 8.  SRAM Read Cycle 1: Address Controlled 
Figure 9.  SRAM Read Cycle 2: CE and OE Controlled 
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Notes
10. WE is HIGH during SRAM Read Cycles.
11. Device is continuously selected with CE and OE both Low.
12. Measured ±200 mV from steady state output voltage.
13. These parameters are guaranteed by design and are not tested.
14. HSB must remain HIGH during READ and WRITE cycles.