Programming instructions

CMOS
Multisim Component Reference Guide 7-2 ni.com
are greater for CMOS than for TTL, except for the 74 ACT series. These series are designed
to be electrically comparable with TTL, so they must accept the same input voltage levels as
TTL.
7.1.3 Noise Margins
The CMOS devices have greater noise margins than TTL.
7.1.4 Power Dissipation
The power dissipation of a CMOS logic circuit is very low when the circuit is in a static state.
The pwoer dissipation of a CMOS IC increases in proportion to the frequency at which the
circuits are switching states.
7.2 4000 Series ICs
7.2.1 4000 (Dual 3-In NOR and INVERTER)
This device contains dual 3-input NOR and Inverters gates.
Logic function:
NOR gate truth table:
O
1
=I
1
+I
2
+I
3
I1 I2 I3 O1
0001
1000
0100
1100
0010
1010
0110
1110
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