G3 5
P3 13
G2 9
P2 12
MC10H179
LOGIC DIAGRAM
3 CN+4
2 GG
CN 11
15 PG
G1 7
P1 10
G0 4
P0 14
PG =
GG =
CN + 2 =
CN + 4 =
P0 + P1 + P2 + P3
(G0 + P1 + P2 + P3) (G1 + P2 + P3) (G2 + P3) G3
(CN + P0 + P1) (G0 + P1) G1
(CN + P0 + P1 + P2 + P3) (G0 + P1 + P2 + P3) (G1 + P2 + P3)
(G2 + P3) G3
6 CN+2
VCC1 = PIN 1
VCC2 = PIN 16
VEE = PIN 8
TYPICAL APPLICATIONS
The MC10H179 is a high−speed, low−power, standard
MECL complex function that is designed to perform the
look−ahead carry function. This device can be used with the
MC10H181 4−bit ALU directly, or with the MC10H180
dual arithmetic unit in any computer, instrumentation or
digital communication application requiring high speed
arithmetic operation on long words.
When used with the MC10H181, the MC10H179
performs a second order or higher look−ahead. Figure 2
shows a 16−bit look−ahead carry arithmetic unit. Second
order carry is valuable for longer binary words. As an
example, addition of two 32−bit words is improved from 30
nanoseconds with ripple−carry techniques. A block diagram
of a 32−bit ALU is shown in Figure 1. The MC10H179 may
also be used in many other applications. It can, for example,
reduce system package count when used to generate
functions of several variables.
FIGURE 1 − 32−BIT ALU WITH CARRY LOOK−AHEAD
Cin
ALU
ALU
Cn
Cn+4
Cn
PG
PG
ALU
Cn Cn+4
PG
ALU
Cn
PG
ALU
Cn Cn+4
PG
ALU
Cn
PG
ALU
Cn Cn+4
PG
ALU
Cn
PG
Add Time =
18 ns typ
Cn
Cn+2
MC10H179
Cn+4
Cn
Cn+2
MC10H179
Cn+4
Cout
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