# VLSI Questions and Answers – MOS Circuit Scaling – 2

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This set of VLSI Multiple Choice Questions & Answers (MCQs) focuses on “MOS Circuit Scaling – 2”.

1. The gate delay is proportional to:
a) Ron .Cg
b) Rs.Cds
c) Rd.Cgs
d) Ron.Cox

Explanation: The gate delay is proportional to channel resistance and gate capacitance

2. The maximum operating frequency is scaled by:
a) 1/α2
b) β/α2
c) α2
d) 1

Explanation: Maximum operating frequency s inversely proportional to the gate delay. It is scaled by α2

3. The saturation current is scaled by the factor of:
a) 1
b) 1/α2
c) 1/β
d) 1/α

Explanation: The saturation current is scaled by the factor of 1/β

4. The scaling factor of current density in constant voltage model is:
a) 1/α2
b) 1
c) α2
d) α2

Explanation: Current density is scaled by a factor of α2/β and since it is in Constant voltage model, β = 1, therefore α2 is correct answer

5. Switching energy per gate is scaled by the factor of:
a) 1
b) α2
c) 1/ β.α2
d) α2

Explanation: Switching energy per gate is scaled by a factor of 1/ β.α2

6. In Constant field model, the scaling factor of switching energy per gate would be:
a) 1/ β.α2
b) 1/ α3
c) 1/ α2
d) All of the mentioned

Explanation: Since in constant field model α = β

7. The power dissipation per gate is scaled as:
a) 1
b) 1/ β.α2
c) α2
d) 1/ β2

Explanation: Power dissipation per gate is scaled by the factor of 1/β2

8. The dynamic component of power dissipation is given by:
a) P = I2.Rd
b) P = Vdd2/Rd
c) P = Eg.fo
d) All of the mentioned

Explanation: The dynamic component is the product of energy per gate and maximum operating frequency.

9. The static component of power dsssipation is given by:
a) P = I2.Rd
b) P = Vdd2/Ron
c) P = Eg.fo
d) All of the mentioned

Explanation: The static component is the power dissipated across transistor when it is in ON state

10. The scaling factor of power dissipation per unit area is:
a) 1
b) 1/α2
c) 1/ β.α2
d) α22

Explanation: The scaling factor of power dissipation per unit area is α22

11. The power speed product has the scaling factor of:
a) 1
b) 1/α2
c) 1/ β.α2
d) None of the mentioned

Explanation: The power speed product has the scaling factor of 1/ β.α2

12. The scaling factor of power dissipation per unit area in constant field model is:
a) 1
b) 1/α2
c) 1/ β.α2
d) α22

Explanation: In constant field model α = β

13. The scaling factor of Logic Level 1 in constant field model is:
a) 1
b) 1/β
c) 1/α
d) α/β

Explanation: The logic level 1 is scaled as 1/β. Since we are using constant field model, the scaling factor will be 1/α

14. The scaling factor similar to scaling factor of power speed product is:
a) Power dissipation per unit area
b) Switching Energy
c) Power dissipation per gate
d) All of the mentioned

Explanation: Switching energy has the same scaling factor as that of power speed products.

15. The parameter which is not scaled to any factor is:
a) Power speed product
b) Switching energy
c) Channel resistance
d) All of the mentioned 