Topic: Digital Electronics
In CMOS designs, why size of PMOS is kept larger than size of NMOS?
- A. To get higher drive strength
- B. To reduce power dissipation
- C. To get balanced rise/fall time
- D. All of above
Answer: C. To get balanced rise/fall time
Explanation: Hole mobility is lower than electron mobility (typically by a factor of 2 to 3). To achieve symmetric transfer characteristics and balanced rise/fall times, the PMOS transistor is sized appropriately larger (wider) than the NMOS transistor.