Question

It is required to design a square wave oscillator that generated a clock of 100MHz. Find the number of inverters cascaded if the propagation delay of each inverter is 1 ns.

Answer 1

To design a square wave oscillator with a clock frequency of 100 MHz, we can use a series of inverters. Each inverter introduces a 1 ns propagation delay. The number of inverters needed can be calculated by dividing the number of cycles in one state by the number of cycles in each inverter.

Step-by-step explanation:

To design a square wave oscillator that generates a clock of 100 MHz, we can use a series of inverters connected in a chain. Each inverter introduces a propagation delay of 1 ns. To calculate the number of inverters required, we need to find the number of cycles in one period of the square wave. The period of the clock is the reciprocal of the frequency, which is 1/(100 MHz).

Since the square wave has a 50% duty cycle, the high and low states each occupy half the period. Therefore, the time for one state is half of the period, which is 0.5/(100 MHz). The number of cycles in one state is equal to the propagation delay of each inverter, which is 1 ns.

Using these values, the number of inverters required can be calculated as the number of cycles in one state divided by the number of cycles in each inverter.

Substituting the values, we get:

0.5/(100 MHz) / (1 ns) = 0.5 x 10⁹ / 1 = 0.5 x 10⁹ inverters.