Zener Regulator

The constant reverse voltage of the zener diode makes it a valuable component for the regulation of the output voltage against both variations in the input voltage from an unregulated power supply or variations in the load resistance. The current through the zener will change to keep the voltage at within the limits of the threshold of zener action and the maximum power it can dissipate.

Zener Regulator Design

One strategy for designing a Zener regulator circuit is to design for a maximum power dissipated in the zener diode when the regulator is open circuited.

For a zener voltage 对于泽纳电压

= V and a maximum power of P = W, = 电压和最大功率为 P = 焦耳， 中文译文中的待填/计算数值依次对应：1：vz 2：pm。实际数值以上方原输入框为准。

the resistor 电阻

must limit the current to 必须限制电流

= mA . = mA 。 中文译文中的待填/计算数值依次对应：1：iz。实际数值以上方原输入框为准。

If the input voltage is 如果输入电压是

= volts, = 伏特， 中文译文中的待填/计算数值依次对应：1：vin。实际数值以上方原输入框为准。

then you will require a resistor 然后你需要一个电阻

=

to protect the zener in open circuit. 以保护齐纳二极管在开路状态下

This design with a load resistance 这种带有负载电阻的设计

=

will give an output current 将产生输出电流

=

mA

and output power 和输出功率

= W

To do this, it will require input power 这将需要输入功率

= W.

The logic of this design strategy is to protect the zener diode. The designed resistor limits the current so that you don't burn out the zener diode if the load resistor gets disconnected.

Calculation note: You may substitute values for the zener voltage, the maximum power, the input voltage, or the load resistor. The other parameters will be calculated. Default values will be entered for unspecified parameters used in the calculation.

If you experiment with the input values, you will discover some of the practical truths about zener-regulated power supplies. If you start with an unregulated power supply which is closer to, but not less than, the zener voltage, you will be able to get more regulated power out without open-circuit risk to the zener diode. The circuit will also be more efficient in power use.