Experiment: Simple Half-Wave Rectifier:

1.

Set up the circuit in Fig. 1.1. For this circuit and all others in this lab, use the 1N4007 diodes that are in your lab kit.

  

Figure 1.1: Positive Half-Wave Rectifier

Set the signal generator to 1kHz with and amplitude of approximately 5V. (Make sure the DC offset on your signal generator is zero.) Sketch the input versus the output as a function of time. Note the difference in voltage between the input and output You should see that only current flowing in the positive direction with respect to the voltage of the signal generator. That is, during the positive half of the cycle, the diode is forward biased, thereby letting current through. During the negative half, the diode is reverse biased and no current can pass.

2.

Reverse the polarity of the diode (turn it around). Now repeat the above exercise. What's the difference in output versus input signals with the diode reversed.

3.

Increase the frequency of your signal generator from 1kHz to 10kHz, 100kHz and 1MHz. What happens, can you think of a reason why?

4.

Set the signal generator back to 1kHz. Calculate the average power being dissipated in the resistor. Recall that average power is given by:

$$P_{avg} = \frac{1}{T}\int^T_0 v(t)i(t)dt$$ (2)

Where T is one period of the signal.