Philips Semiconductors

Product specification

74F283

4-bit binary full adder with fast carry

2

1989 Mar 03

853-0364 95944

FEATURES

DESCRIPTION

The 74F283 adds two 4-bit binary words (An plus Bn) plus the

incoming carry. The binary sum appears on the sum outputs

(

=

where (+)=plus

Due to the symmetry of the binary add function, the 74F283 can be

used with either all active-High operands (positive logic) or with all

active-Low operands (negative logic). See Function Table. In case of

all active-Low operands (negative logic) the results

should be interpreted also as active-Low. With active-High inputs,

intended. Interchanging inputs of equal weight does not affect the

7, etc.

Due to pin limitations, the intermediate carries of the 74F283 are not

brought out for use as inputs or outputs. However, other means can

be used to effectively insert a carry into, or bring a carry out from, an

intermediate stage.

PIN CONFIGURATION

7

14

13

12

11

10

9

6

5

4

3

2

1

B2

A3

B3

A0

B1

B0

Σ1

GND

A1

Σ0

SF00852

Σ3

Σ2

A2

8

16

15

TYPE

TYPICAL

PROPAGATION

DELAY

TYPICAL

SUPPLY CURRENT

(TOTAL)

74F283

6.5ns

40mA

ORDERING INFORMATION

DESCRIPTION

COMMERCIAL RANGE

PKG DWG #

16-pin plastic DIP

N74F283N

SOT38-4

16-pin plastic SO

N74F283D

SOT109-1

INPUT AND OUTPUT LOADING AND FAN-OUT TABLE

PINS

DESCRIPTION

74F(U.L.)

HIGH/LOW

LOAD VALUE

HIGH/LOW

A0 - A3

A operand inputs

1.0/2.0

20

µA/1.2mA

B0 - B3

B operand inputs

1.0/2.0

20

µA/1.2mA

Carry input

1.0/1.0

20

µA/0.6mA

Carry output

50/33

1.0mA/20mA

Σ0–Σ3

Sum outputs

50/33

1.0mA/20mA

NOTE:

One (1.0) FAST Unit Load is defined as: 20

µA in the High state and 0.6mA in the Low state.

LOGIC SYMBOL

5

6

3

2

14 15 12 11

41

Σ1

Σ0

A0 B0 A1 B1 A2 B2 A3 B3

SF00853

13

10

Σ3

Σ2

9

7

GND=Pin 8

LOGIC SYMBOL (IEEE/IEC)

5

3

14

12

6

2

15

11

7

10

9

Σ

Σ

SF00854

13

1

4

CO

CI

0

3

0

3

P

Q

0

3