SN74ALS235

64 × 5 ASYNCHRONOUS FIRST IN, FIRST OUT MEMORY

SDAS108A − OCTOBER 1986 − REVISED SEPTEMBER 1993

11

POST OFFICE BOX 655303

POST OFFICE BOX 1443

switching characteristics (see Figure 9)

PARAMETER

FROM

(INPUT)

TO

(OUTPUT)

VCC = 5 V,

CL = 50 pF,

R1 = 500

Ω,

R2 = 500

Ω,

TA = 25°C

VCC = 4.5 V to 5.5 V,

CL = 50 pF,

R1 = 500

Ω,

R2 = 500

Ω,

TA = MIN to MAX†

UNIT

MIN

TYP

MAX

MIN

MAX

fmax

SI

30

25

MHz

fmax

SO

30

25

MHz

tw‡

IR high

15

8

ns

tw§

OR high

19

8

ns

td(QV-ORH)

Q valid before OR

↑

6

9

−5

12

ns

td(SOL-QX)

Q valid after SO

↓

13

4

ns

tpd

SI

↓

Q

600

800

350

1000

ns

tPHL

SI

↑

IR

20

26

8

30

ns

tPLH

SI

↓

IR

16

21

6

25

ns

tPLH¶

SI

↓

OR

600

800

350

1000

ns

tPHL

SI

↓

AF/AE

550

700

290

880

ns

tPLH

SI

↓

AF/AE

85

115

40

150

ns

tPLH

SI

↓

HF

340

410

180

510

ns

tpd

SO

↓

Q

13

17

4

22

ns

tPHL

SO

↑

OR

23

27

7

33

ns

tPLH

SO

↓

OR

20

24

6

30

ns

tPLH¶

SO

↓

IR

600

800

350

1000

ns

tPHL

SO

↓

AF/AE

550

700

290

880

ns

tPLH

SO

↓

AF/AE

85

115

35

150

ns

tPHL

SO

↓

HF

340

410

170

510

ns

tPHL

RST

↓

OR

22

26

10

34

ns

tPLH

RST

↑

IR

12

18

5

22

ns

tPHL

RST

↓

IR

12

18

5

22

ns

tPHL

RST

↓

Q

14

17

5

19

ns

tdis

OE

↑

Q

7

13

2

15

ns

ten

OE

↓

Q

6

12

2

13

ns

† For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.

‡ The IR output pulse occurs when the FIFO is full, SI is high, and SO is pulsed (see Figure 4).

§ The OR output pulse occurs when the FIFO is empty, SO is high, and SI is pulsed (see Figure 3).

¶ Data throughput or fall-through times