NEIEP Mechanics Practice Exam

How are Zener diodes typically connected in a circuit?

1. In reverse biased configuration

2. In parallel with the load

3. In series with the supply

4. In forward biased configuration

The correct answer is: In reverse biased configuration

Zener diodes are specifically designed to operate in reverse bias when they are used for voltage regulation. In this configuration, they can maintain a stable output voltage across the load despite variations in the input or load current. When the reverse voltage applied to the Zener diode exceeds its breakdown voltage, it begins to conduct and maintain a constant voltage output. This characteristic makes Zener diodes ideal for voltage regulation applications. In a circuit, when connected in reverse bias, Zener diodes effectively clamp the voltage to a specified level, protecting downstream components from over-voltage conditions. This is crucial for ensuring that sensitive electronic devices operate within their specified voltage parameters. The other configurations mentioned do not utilize the unique properties of Zener diodes. For instance, connecting them in series with the supply is not effective for voltage regulation, as it would not allow the diode to operate in its breakdown region. Similarly, while they can be connected in parallel with a load, it is the reverse bias connection that primarily defines their role as voltage regulators.