Question

If a centre tap transformer is used with two p-n junction diodes for full wave rectification then output voltage of rectifier with respect to each diode is (secondary voltage of transformer $= V_s$ )

• A. $2 V_s$
• B. $\left( \frac{2}{3} \right) V_s$
• C. $\left( \frac{1}{2} \right) V_s$
• D. $\left( \frac{3}{2} \right) V_s$

Hint:

A centre tap divides the secondary winding into two equal halves, so each side gives half of the total secondary voltage.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
A center-tapped full-wave rectifier works by splitting the secondary winding of the transformer into two equal halves. Each half serves one diode in alternate half-cycles.
Step 2: Key Formula or Approach:
Output voltage per diode phase $= \frac{\text{Secondary Total Voltage}}{2}$.
Step 3: Detailed Explanation:
The secondary of the transformer has a total voltage $V_s$. The center tap connection effectively makes two sources from one secondary winding.
During the positive half-cycle, one diode conducts, and it sees half of the secondary voltage.
During the negative half-cycle, the other diode conducts, seeing the other half of the secondary voltage.
Since each diode only handles one-half of the winding, the peak voltage relative to each diode path is $\frac{1}{2} V_s$.
Step 4: Final Answer:
The output voltage relative to each diode is $\left( \frac{1}{2} \right) V_s$.