Zenerdiodisäätö

Zenerdiodisäätö, also known as Zener diode regulation, is a simple and widely used electronic circuit technique for voltage stabilization. It utilizes the unique characteristic of a Zener diode, which is designed to conduct current in the reverse direction when a specific voltage, known as the Zener voltage (Vz), is reached. This property makes it ideal for maintaining a constant output voltage even when the input voltage or the load current varies.

A typical Zener diode regulator circuit consists of a Zener diode, a current-limiting resistor, and the load connected in parallel with the Zener diode. The input voltage is applied across the series combination of the resistor and the parallel Zener diode/load. When the input voltage is below the Zener voltage, the diode is in its breakdown region and does not conduct significantly, so the output voltage follows the input voltage. However, once the input voltage exceeds the Zener voltage, the diode starts to conduct in reverse, clamping the voltage across itself and the load to its Zener voltage.

The current-limiting resistor is crucial for protecting the Zener diode from excessive current. It drops the excess voltage and ensures that the diode operates within its safe power dissipation limits. If the input voltage increases, the Zener diode draws more current, and the resistor drops more voltage, keeping the output voltage constant. Conversely, if the load current increases, the Zener diode draws less current, and the total current through the resistor remains relatively constant, again maintaining the output voltage. Zener diode regulators are commonly employed in low-power applications where a stable voltage reference is required, such as in power supplies for sensitive electronic components or as a voltage reference in measurement circuits.