CMOS vs TTL

• What are the Basic Differences Between CMOS and TTL Signals?

CMOS compared to TTL:

CMOS components are typically more expensive that TTL equivalents.
However, CMOS technology is usually less expensive on a system level due to CMOS chips being smaller and requiring less regulation.

CMOS circuits do not draw as much power as TTL circuits while at rest.
However, CMOS power consumption increases faster with higher clock speeds than TTL does.  Lower current draw requires less power supply distribution, therefore causing a simpler and cheaper design.

Due to longer rise and fall times, the transmission of digital signals become simpler and less expensive with CMOS chips.

CMOS components are more susceptible to damage from electrostatic discharge than TTL compenents.

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