SN74ACT7808

2048

× 9 STROBED FIRST-IN, FIRST-OUT MEMORY

SCAS205E – FEBRUARY 1991 – REVISED NOVEMBER 2001

9

POST OFFICE BOX 655303

timing requirements over recommended operating conditions (unless otherwise noted) (see

Figures 1 through 3)

’ACT7808-20

’ACT7808-25

’ACT7808-30

’ACT7808-40

UNIT

MIN

MAX

MIN

MAX

MIN

MAX

MIN

MAX

UNIT

fclock

Clock frequency

50

40

33.3

25

MHz

LDCK high or low

8

9

11

13

t

Pulse duration

UNCK high or low

8

9

11

13

ns

tw

Pulse duration

PEN low

9

9

11

13

ns

RESET low

10

13

16

19

D0–D8, DP9 before LDCK

↑

5

5

5

5

tsu

Setup time

LDCK inactive

before RESET high

5

5

5

5

ns

PEN before LDCK

↑

5

5

5

5

D0–D8, DP9 after LDCK

↑

0

0

0

0

th

Hold time

LDCK inactive

after RESET high

5

5

5

5

ns

h

PEN low after LDCK

↑

4

4

4

4

PEN high after LDCK low

0

0

0

0

switching characteristics over recommended ranges of supply voltage and operating free-air

PARAMETER

FROM

TO

’ACT7808-20

’ACT7808-25

’ACT7808-30

’ACT7808-40

UNIT

PARAMETER

(INPUT)

(OUTPUT)

MIN

TYP†

MAX

MIN

MAX

MIN

MAX

MIN

MAX

UNIT

fmax

LDCK or UNCK

50

40

33.3

25

MHz

t

LDCK

↑

Any Q

5

20

5

22

5

25

5

28

ns

tpd

UNCK

↑

Any Q

4.5

11

15

4.5

18

4.5

20

4.5

22

ns

tpd‡

UNCK

↑

Any Q

10

ns

tPLH

LDCK

↑

EMPTY

4

15

4

17

4

19

4

21

ns

UNCK

↑

EMPTY

2

15

2

17

2

19

2

21

tPHL

RESET low

EMPTY

2

16

2

18

2

20

2

22

ns

PHL

LDCK

↑

FULL

4

15

4

17

4

19

4

21

tPLH

UNCK

↑

FULL

4

14

4

16

4

18

4

20

ns

tPLH

RESET low

FULL

2

18

2

20

2

22

2

24

ns

t d

LDCK

↑

AF/AE

2

16

2

18

2

20

2

22

ns

tpd

UNCK

↑

AF/AE

2

16

2

18

2

20

2

22

ns

tPLH

RESET low

AF/AE

0

10

0

12

0

14

0

16

ns

tPLH

LDCK

↑

HF

2

19

2

21

2

23

2

25

ns

tPHL

UNCK

↑

HF

2

16

2

18

2

20

2

22

ns

tPHL

RESET low

HF

2

12

2

14

2

16

2

18

ns

tPLH

UNCK

↑

XO

2

11

2

13

2

15

2

17

ns

tPHL

LDCK

↑

XO

2

11

2

13

2

15

2

17

ns

ten

OE

Any Q

1

10

1

12

1

14

1

16

ns

tdis

OE

Any Q

1

9

1

11

1

13

1

15

ns

ten

XI high

Any Q

3

13

3

15

3

17

3

19

ns

tdis

XO high

Any Q

4

4

4

4

ns

† All typical values are at VCC = 5 V, TA = 25°C.

‡ This parameter is measured with CL = 30 pF (see Figure 4).