SN74ALS990

8-BIT D-TYPE TRANSPARENT READ-BACK LATCH

SDAS027B – APRIL 1984 – REVISED JANUARY 1995

4

POST OFFICE BOX 655303

switching characteristics (see Figure 1)

PARAMETER

FROM

(INPUT)

TO

(OUTPUT)

VCC = 4.5 V to 5.5 V,

CL = 50 pF,

TA = MIN to MAX†

UNIT

()

()

MIN

MAX

tPLH

D

Q

4

17

ns

tPHL

D

Q

5

24

ns

tPLH

LE

Q

6

26

ns

tPHL

LE

Q

8

26

ns

ten‡

OERB

D

4

21

ns

tdis§

OERB

D

4

19

ns

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

‡ ten = tPZH or tPZL

§ tdis = tPHZ or tPLZ