Philips Semiconductors

Product specification

74F381

Arithmetic Logic Unit

1989 Mar 01

5

FUNCTION SELECT TABLE

SELECT

OPERATING

MODE

S0

S1

S2

OPERATING

MODE

L

L

L

Clear

H

L

L

B minus A

L

H

L

A minus B

H

H

L

A Plus B

L

L

H

A

B

H

L

H

A + B

L

H

H

AB

H

H

H

Preset

H = High voltage level

L

= Low voltage level

Table 1. 16-Bit Delay Tabulation

PATH SEGMENT

TOWARD

F

OUTPUT

Cn+4, OVR

Ai or Bi to P

7.2ns

7.2ns

Pi to Cn+i (74F182)

6.2ns

6.2ns

Cn to F

8.1ns

–

Cn to Cn+4, OVR

–

8.0ns

Total Delay

21.5ns

21.4ns

APPLICATION

A

B

Cn

SF00925

S

F

Q

P

74F381

F0–F3

4

4

3

3

A0–A3

B0–B3

G0

P0

Cn+x

A

B

Cn

S

F

Q

P

74F381

F4–F7

4

4

3

A4–A7

B4–B7

G1

P1

Cn+y

A

B

Cn

S

F

Q

P

74F381

F8–F11

4

4

3

A8–A11

B8–B11

G2

P2

Cn+z

A

B

Cn

S

F

74F382

F12–F15

4

4

3

A12–A15

B12–B15

Cn+4

OVR

74F182

OVERFLOW

Cn

SELECT

Figure 1. 16-bit Look-ahead Carry ALU Expansion

ABSOLUTE MAXIMUM RATINGS

(Operation beyond the limit set forth in this table may impair the useful life of the device. Unless otherwise noted these limits are over the

operating free-air temperature range.)

SYMBOL

PARAMETER

RATING

UNIT

Supply voltage

–0.5 to +7.0

V

Input voltage

–0.5 to +7.0

V

Input current

–30 to +1

mA

Voltage applied to output in High output state

V

Current applied to output in Low output state

40

mA

Operating free-air temperature range

0 to +70

Storage temperature range

–65 to +150