Switching waveforms, Switching characteristics – Cypress CY7C138 User Manual
Page 6
CY7C138, CY7C139
Document #: 38-06037 Rev. *D
Page 6 of 17
t
HD
Data Hold From Write End
0
0
0
0
ns
t
HZWE
R/W LOW to High Z
10
15
20
25
ns
t
LZWE
R/W HIGH to Low Z
3
3
3
3
ns
t
WDD
Write Pulse to Data Delay
30
50
60
70
ns
t
DDD
Write Data Valid to Read Data Valid
25
30
35
40
ns
BUSY TIMING
t
BLA
BUSY LOW from Address Match
15
20
20
45
ns
t
BHA
BUSY HIGH from Address Mismatch
15
20
20
40
ns
t
BLC
BUSY LOW from CE LOW
15
20
20
40
ns
t
BHC
BUSY HIGH from CE HIGH
15
20
20
35
ns
t
PS
Port Set-Up for Priority
5
5
5
5
ns
t
WB
R/W LOW after BUSY LOW
0
0
0
0
ns
t
WH
R/W HIGH after BUSY HIGH
13
20
30
40
ns
t
BDD
BUSY HIGH to Data Valid
Note 15
ns
INTERRUPT TIMING
t
INS
INT Set Time
15
25
25
30
ns
t
INR
INT Reset Time
15
25
25
30
ns
SEMAPHORE TIMING
t
SOP
SEM Flag Update Pulse (OE or SEM)
10
10
15
20
ns
t
SWRD
SEM Flag Write to Read Time
5
5
5
5
ns
t
SPS
SEM Flag Contention Window
5
5
5
5
ns
Switching Characteristics
Over the Operating Range
[9]
(continued)
Parameter
Description
7C138-15
7C139-15
7C138-25
7C139-25
7C138-35
7C139-35
7C138-55
7C139-55
Unit
Min
Max
Min
Max
Min
Max
Min
Max
Notes
9. Test conditions assume signal transition time of 3 ns or less, timing reference levels of 1.5V, input pulse levels of 0 to 3.0V, and output loading of the specified
I
OI
/I
OH
and 30-pF load capacitance.
10. At any given temperature and voltage condition for any given device, t
HZCE
is less than t
LZCE
and t
HZOE
is less than t
LZOE
.
11. Test conditions used are Load 3.
12. This parameter is guaranteed but not tested.
13. For information on part-to-part delay through RAM cells from writing port to reading port, refer to Read Timing with Port-to-Port Delay waveform.
14. Test conditions used are Load 2.
15. t
BDD
is a calculated parameter and is the greater of t
WDD
– t
PWE
(actual) or t
DDD
– t
SD
(actual).
Switching Waveforms
Figure 3. Read Cycle No. 1 (Either Port Address Access)
Figure 4. Read Cycle No. 2 (Either Port CE/OE Access)
t
RC
t
AA
t
OHA
DATA VALID
PREVIOUS DATA VALID
DATA OUT
ADDRESS