Calculations

Pulse Width Modulation_741

Calculations & Observations

The width of the pulse can be described in terms of its duty cycle, which is defined as:
d = t_w / t_d × 100 % Where,
t_w = width of pulse
t_d = period of the pulse
Here, t_d is constant and t_w varies.

In Pulse Width Modulation there is a linear relationship between duty cycle (d) and amplitude of message signal (V_in). This relationship is as following:
d ∝ V_in
⇒ d = M_d . V_in
Where, M_d is the modulation index.

Fig.1 Output of Pulse Width Modulation Signal.

Fig.2 Output of Pulse Width Modulation Signal.

Fig.3 Output of Pulse Width Modulation Signal.