Question: what are the basic differences between cmos and ttl signals?
Answer: CMOS has longer rise and fall times thus digital signals are simpler and less expensive with the CMOS chips. There is a substantial difference in the voltage level range for both. For TTL it is 4.75 V to 5.25 V while for CMOS it ranges between 0 to 1/3 VDD at a low level and 2/3VDD to VDD at high levels.