What is the difference between TTL and CMOS?
CMOS stands for Complimentary Metal-oxide Semicodictor while in TTL stand for Transistor-Transistor Logic. CMOS circuit uses a field-effect transistor by connecting NMOS and PMOS, the TTL circuit uses bipolar junction transistor. The design of the CMOS can be considered to be very simpler as compared to the TTL.
Which is faster TTL or CMOS?
TTL chips are generally faster than CMOS gates (but see ACT series), however there are two logic technologies faster than TTL-Emitter-coupled logic (ECL) and gallium arsenide (GaAs). These chips come at considerable cost in power consumption and ease of interface to other logic families.
What is an advantage of TTL over CMOS?
Following points summarize TTL advantages over ECL and CMOS: ➨It is most rugged meaning least sysceptible to electrical damage. ➨It has strong drive capability. ➨It is faster in some versions.
Why TTL logic is used?
TTL is particularly well suited to bipolar integrated circuits because additional inputs to a gate merely required additional emitters on a shared base region of the input transistor. If individually packaged transistors were used, the cost of all the transistors would discourage one from using such an input structure.
What is TTL and CMOS logic family?
The types of logic devices are classified in “families”, of which the most important are TTL and CMOS. The main families are: TTL (Transistor-Transistor Logic), made of bipolar transistors. CMOS (Complementary Metal Oxide Semiconductor) made from MOSFETs. ECL (Emitter Coupled Logic) for extremely high speeds.
Is TTL logic still used?
The term “TTL” is applied to many successive generations of bipolar logic, with gradual improvements in speed and power consumption over about two decades. The most recently introduced family 74Fxx is still sold today (as of 2019), and was widely used into the late 90s.
What is the main disadvantage of TTL devices?
A disadvantage of the “totem-pole” output stage is the decreased voltage level (no more than 3.5 V) of the output logical “1” (even if the output is unloaded).
What is the disadvantage of TTL?
The disadvantages are: limited speed and frequency, noisy, very high power consumption at higher frequencies.
What is the advantages of TTL?
This is the major advantage. As transistor becomes ON and OFF much rapidly than a diode, switching time will be faster. TTL, or Transistor-transistor logic replaced resistor-transistor logic, and used much less power. The TTL family is very fast and reliable, and newer faster, less power-consuming, etc.