Motorola CMOS Logic Manual page 480

A1
A1 A2 A3 A4
C
MC14561
C
Z
F1 F2 F3 F4
A1 A2 A3 A4
C in
S1
A1
C
C
Z
F1
A S
1/4 MC14070
B S
B S
ADD/SUB
1/4 MC14070
V DD
B1
A1 A2 A3 A4
C
MC14561
C
Z
F1 F2 F3 F4
B1 B2 B3 B4
C out
MC14560
S2 S3 S4
A2 A3 A4
MC14561
F2 F3 F4
R1
A
B
M 5
C
W
D
E
V DD
MC14530
A
B
W
C
M 5
D
E
A2 B2
MC14561 MC14561
MC14560
MC14561
R2
EAC
C out
1/4 MC14070
Z
Z
SIGN
µ
Typical Add/Subtract Time = 0.6 + 0.4n s
where n = Number of Decades
A n B n
MC14561 MC14561
C out
MC14560
MC14561
R n
OVERFLOW
SIGN OF R S