©1986 Fairchild Semiconductor Corporation

www.fairchildsemi.com

DM74AS257, DM74AS258 Rev. 1.2

5

DM74AS257 Switching Characteristics

Over recommended operating free air temperature range.

DM74AS258 Switching Characteristics

Over recommended operating free air temperature range.

Symbol

Parameter

Conditions

From

To

Min

Max

Units

Propagation Delay Time,

LOW-to-HIGH Level Output

Data

Any Y

1

5.5

ns

Propagation Delay Time,

HIGH-to-LOW Level Output

16

ns

Propagation Delay Time,

LOW-to-HIGH Level Output

Select

Any Y

2

11

ns

Propagation Delay Time,

HIGH-to-LOW Level Output

210

ns

Output Enable Time to HIGH

Level

OUTPUT

Control

Any Y

2

7.5

ns

Output Enable Time to LOW

Level

2

9.5

ns

Output Disable Time from HIGH

Level

OUTPUT

Control

Any Y

1.5

6.5

ns

Output Disable Time from LOW

Level

27

ns

Symbol

Parameter

Conditions

From

To

Min.

Max.

Units

Propagation Delay Time,

LOW-to-HIGH Level Output

Data

Any Y

1

5

ns

Propagation Delay Time,

HIGH-to-LOW Level Output

14

ns

Propagation Delay Time,

LOW-to-HIGH Level Output

Select

Any Y

2

9.5

ns

Propagation Delay Time,

HIGH-to-LOW Level Output

210

ns

Output Enable Time to HIGH

Level

OUTPUT

Control

Any Y

2

8

ns

Output Enable Time to LOW

Level

210

ns

Output Disable Time, from HIGH

Level

OUTPUT

Control

Any Y

1.5

6

ns

Output Disable Time from LOW

Level

2

6.5

ns