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Selection of Current-Limiting Resistor in Voltage-stabilizing Rectifier Diode Circuit

How to select the current limiting resistor of the voltage stabilizing rectifier diode circuit? Recently, the editor often receives the question of the selection of resistors. Today, the editor will popularize what is called the selection of current-limiting resistors for voltage-stabilizing diode circuits:

If R is too large, Ir is very small. When Il increases, the current of the voltage regulator tube may be reduced below the critical value, and the voltage stabilizing effect will be lost;

If R is too small, Ir will be very large. When Rl is large or open circuited, Ir will flow to the voltage regulator tube, which may exceed its allowable rating and cause damage.

Formula:

(Uimin-Uz)/(Izmin+Ilmax)>R>(Uimax-Uz)/(Izmax+Ilmin)

When the two cannot be satisfied at the same time, it means that the working range of the Rectifier Diode has been exceeded under the given conditions, and it is necessary to limit the variation range of the input voltage Ui or the load current Il, or choose a larger capacity Zener tube.

Izmax: the maximum operating current allowed by the Zener tube

Uzmax: rectified output voltage when the grid voltage is the highest

Ilmax: the maximum value of the load current

These are the conversion formulas for the resistance data of the voltage-stabilizing rectifier diode. Have you learned about the selection of the current-limiting resistor of the voltage-stabilizing rectifier diode circuit? If you want to know more knowledge, welcome to call the editor.