High noise immunity 3. Low Fan-out 4. Comparatively high logic voltage swing. More Logic Families Questions Q1. Which of the following logic is the fastest? Which one of the following is the most widely used logic family? The noise margins, NMhigh and NMlow, respectively, will be:. Which one of the the following logic family has least propagation delay? Which one of the following logic family comprises of BJTs? The performance parameters of a logic family are required for better understanding.
The following statements explain the characteristics of Digital logic family. Which of these statements are correct? A The operating speed of a logic family is determined from its propagation delay B Power dissipation is inversely proportional to switching frequency and directly proportional to cycle time C Fan-in is defined as maximum number of inputs for a logic gate in a particular logic family D Fan-out is defined as number of dissimilar logic gates driven by a single logic gate Choose the most appropriate answer from the options given below:.
Electronics Engineering. Solid State Physics. See Answer. Best Answer. Study guides. Q: Why Pmos transistor is usually larger than Nmos transistor in layout? Write your answer Related questions. Why a NMOS transistor pass strong 0 but week 1? What is advantage of CMOS setup? What are sleep transistors? What is the difference between cmos and nmos? What is the use of pseudo nMOS gates in digital design?
What type of doping have the drain and the source of a PMOS transistor? What are the differences between nmos and pmos transistors? What is NMOS in electronics? What is the start up memory chip called in a computer? Is cmos a combination of both nmos and pmos? What is the fullform nmos switches in microprocessor? What happens if you interchange pmos and nmos in a cmos inverter? Why p substrate is used in nmos?
What are advantages of transmission gate logic over Cmos logic? What are the Advantages of cmos over pmos and nmos? What happens if you change pmos to nmos and nmos to pmos in cmos? What is baising? What is abbreviation NMOS? This can be achieved only by sizing the pmos 3 times to the nmos sizing.
May I ask: what is the importance of the same voltage rise and fall time in the circuit? SkyHigh Advanced Member level 1. To be exact, PMOS should be 2. Larger is actually not a good one. In fact, it should be longer in Gate Width because only increasing the Width decreases the resistance.
BTW, someone mentioned Noise Margin. CMOS has one undefined voltage band between upper and lower margin for logic 1 and 0 respectively. It is impossible to get an infinite gain that results such undefined voltage band. The actual rise and fall time is still the determined by the logic gates in the digital circuit. Having CMOS inverter nicely tuned is only the tip of an iceberg. By means of Lambda scale to Gate Length, this is easily done in Cadence tools.
Therefore focus should emphasize more on trying to balance the logic gates to ensure fast rise and fall times in various logic conditions so as to elilminate race conditions and static hazards. One has shorter rise time, but longer fall times.
The other has longer rise time, but shorter fall times. So the logic circuit should have fast fall and rise time But I am still wondering what is the importance of symmetrical rise and fall time.
Click to expand If your circuit run at high frequency, and the die size and power consumption must be optimized, it had better that let the rise time is equal to the fall time. This scaling factor varies with the technology. Yes, this is true that we make PMOS 2. Is that still true when we encounter very short channel device and both NMOS and PMOS transistor have movility saturation that means their mobilities are almost same under high electronic field.
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