3Pulse Width Modulation a) We will now modulate the 555 output pulse width by applying a voltage level to the control pin of the 555 (at pin 5). Set the

input trigger frequency to 1 kHz and use a 0.1 µF capacitor. Record the width of the output pulse as a function of the control voltage input for the following values. Question 5 What happened between control voltages of 3.33, 4, and 5.00 V? Explain this behavior in terms of the equation you just derived. Question 4 Why is the 555 output pulse width the same for a control voltage of 3.33 V as it is when there is no input control voltage? Explain why and how the output pulse width depends on the control voltage. Derive an equation describing the effect of the control voltage on the pulse width and compare your results to theoretical values from the equation. b) Show the output pulse width from simulations when control voltages are at 3.33, 4 and 5.00V.

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