Programming instructions

 National Instruments Corporation 7-1 Multisim Component Reference Guide
Chapter 7
CMOS
7.1 CMOS Overview
The complementary MOS (CMOS) logic family uses both P- and N-channel MOSFETS in
the same circuit. CMOS is faster and consumes less power than the other MOS families.
CMOS ICs provide not only all of the same logic functions available in TTL, but also several
special functions not provided by TTL.
The 74C series is pin-compatible (pin configuration of the two ICs are the same) with and
functionally equivalent to TTL devices with the same number. Many but not all functions that
are available in TTL are also available in the 74C series. It is possible then to replace some
TTL circuits with an equivalent design.
The 74HC/HCT series is an improved version of the 74C series. It has a tenfold increase in
switching speed compared to the 74LS devies and a higher output current capability than that
of the 74C. The 74HC/HCT ICs are pin-compatible with and functionally equivalent to TTL
ICs with the same number. 74HCT devices are electrically compatible with TTL, but devices
from the 74C series are not.
7.1.1 Power-Supply Voltage
The 4000/14000 series and 74C series devices can operate with V
DD
values ranging from 3 to
15 V. The 74HC/HCT and 74AC/ACT series operate over a range of supply voltages between
2 and 6 V.
7.1.2 Logic Voltage Levels
The input and ouput voltage levels are different for each CMOS series. The V
OL
for the
CMOS devices is close to 0 V and the V
ON
is close to 5 V. The required input voltage levels
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