Common Base Configuration of a Transistor

In a common base configuration of a transistor, the base terminal is common to both the input and output circuits, while the emitter terminal is the input and the collector terminal is the output. This configuration is commonly used for applications that require high voltage gain and low output resistance.

Explanation of the Correct Answer: Option D

The correct answer for a common base configuration of a transistor is option D, which states "high voltage gain, low output resistance."

High Voltage Gain:
In a common base configuration, the input signal is applied to the emitter terminal and the output signal is taken from the collector terminal. The voltage gain in this configuration is typically high. This is because the input current is amplified by the transistor, and the output voltage is a function of this amplified current. As a result, a small input voltage can produce a large output voltage, resulting in high voltage gain.

Low Output Resistance:
In a common base configuration, the output resistance is typically low. This means that the transistor can deliver a relatively large amount of current to the load without significant voltage drop. The low output resistance allows the transistor to drive low impedance loads effectively.

Other Options:
Let's briefly discuss why the other options are incorrect:

- Option A: low input resistance, high output resistance
This is not correct for a common base configuration. The input resistance is typically low, while the output resistance is typically high.

- Option B: low current gain, low input resistance
This is not correct for a common base configuration. The current gain, also known as the current transfer ratio, is typically high in this configuration.

- Option C: low voltage gain, high current gain
This is not correct for a common base configuration. The voltage gain is typically high, while the current gain is typically lower compared to other configurations like common emitter or common collector.

Therefore, the correct answer for a common base configuration of a transistor is option D, which states "high voltage gain, low output resistance."