How should a Zener Diode be connected for proper operation?

For proper operation, a Zener diode should be connected in reverse bias. This configuration allows the Zener diode to maintain a stable voltage across its terminals, a critical feature used in voltage regulation applications. When reverse biased beyond its breakdown voltage, the Zener diode starts conducting in the reverse direction, allowing current to flow through it while clamping the voltage to the specified Zener voltage. This property makes it an effective component for ensuring that the output voltage remains stable despite fluctuations in input voltage or load conditions.

In contrast, connecting a Zener diode in forward bias would not utilize its voltage regulation capabilities and would behave like a standard diode, allowing current to flow in only one direction without stabilizing the reverse voltage. Connecting it in series with a resistor does not explicitly describe a complete functional application for voltage regulation; it may limit current but does not address how to properly bias the Zener. Finally, while a Zener diode can be placed in parallel with a load in a functioning circuit (often in conjunction with a current-limiting resistor), the critical operation aspect focuses on reverse bias for voltage regulation. Thus, reverse bias connection is essential for it to function as intended.