If switching frequency doubles, dynamic power ...

If switching frequency doubles, dynamic power ...

• A. Remains the same.
• B. Halves.
• C. Becomes negligible.
• D. Doubles.

Answer: (D)

Dynamic power in digital circuits increases with how often the circuit switches. Each toggle charges and discharges the capacitive loads, dissipating energy roughly proportional to C V^2 per transition. The total energy converted to heat per second depends on how many transitions occur each second, which is the switching frequency f. Putting that together, the dynamic power is P_dyn ≈ α C V^2 f, where α is the activity factor (how often the gate actually switches on average). So, if the switching frequency doubles while voltage and capacitance stay the same, dynamic power doubles. The energy per transition stays about the same, but there are twice as many transitions each second, leading to twice the power.

Dynamic power in digital circuits increases with how often the circuit switches. Each toggle charges and discharges the capacitive loads, dissipating energy roughly proportional to C V^2 per transition. The total energy converted to heat per second depends on how many transitions occur each second, which is the switching frequency f. Putting that together, the dynamic power is P_dyn ≈ α C V^2 f, where α is the activity factor (how often the gate actually switches on average). So, if the switching frequency doubles while voltage and capacitance stay the same, dynamic power doubles. The energy per transition stays about the same, but there are twice as many transitions each second, leading to twice the power.