Question

A signal, as shown in the figure, is applied to a p-n junction diode. Identify the output across the resistance \( R_L \):

Hint:

In a rectifier circuit, a forward-biased diode allows current flow, while a reverse-biased diode blocks current. The output waveform corresponds to the rectified portion of the input signal.

Answer 1

The circuit consists of a p-n junction diode in series with a load resistor \( R_L \). The input signal alternates between \( +5 \, \text{V} \) and \( -5 \, \text{V} \). The behavior of the diode depends on the polarity of the input signal:
1. Positive Half-Cycle (\(+5 \, \text{V}\)): The diode is forward biased during the positive half-cycle. This allows current to flow through the load resistor \( R_L \), and the output voltage across \( R_L \) is equal to the input voltage of \( +5 \, \text{V} \).
2. Negative Half-Cycle (\(-5 \, \text{V}\)): The diode is reverse biased during the negative half-cycle. In this condition, the diode does not conduct, and no current flows through \( R_L \). The output voltage across \( R_L \) is zero during this phase.
The output waveform across \( R_L \) consists only of the positive half-cycles of the input signal, and its amplitude is \( +5 \, \text{V} \).