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How to choose a Zener diode?

Zener diodes are usually used in regulated power supplies as a reference power supply and work in reverse breakdown state. When using, pay attention to the positive and negative connections. The positive pole of the tube is connected to the negative pole of the power source, and the negative pole of the tube is connected to the positive pole of the power source. When choosing the voltage regulator tube, it should be considered according to the specific electronic circuit. For a simple parallel regulated power supply, the output voltage is the stable voltage of the Zener diode. The voltage stabilizing source of the transistor radio can be 2CW54 type voltage stabilizing tube, and the stabilizing voltage can reach 6.5V.
The voltage stabilization value of the Zener diode is very discrete, even if the products of the same manufacturer and the same model have different stable voltage values, attention should be paid to the selection. For circuits with higher requirements, the adjustment value should be tested before selection. For overvoltage protection Zener diodes, the stable voltage should be selected according to the protection voltage. The stable voltage value must not be too large or too small, otherwise it will not play a role in voltage protection.
When using a voltage regulator, it should be noted that the reverse current of the Zener diode cannot increase indefinitely, otherwise the Zener diode will be damaged due to overheating. Therefore, the Zener diode usually needs a series current limiting resistor in the circuit. When choosing a Zener diode, if you need a tube with a larger voltage regulation value, but it is not available at the maintenance site, you can use several tubes with a lower voltage regulation value in series. When a tube with a lower voltage regulation value is needed and cannot be purchased, a normal silicon diode forward connection can be used instead of the Zener diode. For example, two 2CA82A silicon diodes connected in series can be used as a 1.4V voltage regulator. However, it is generally not allowed to use Zener tubes in series.
When choosing a Zener diode, in addition to parameters such as stable voltage and maximum operating current, attention should also be paid to choosing a Zener diode with a smaller dynamic resistance, because the smaller the dynamic resistance, the better the voltage regulation performance. For example, the dynamic resistance of the 2CW53 regulator is less than 500 ohms, and the dynamic resistance of the 2CW55 regulator diode is less than 10 ohms.
The above explanation is the method of choosing Zener diodes. I hope it will be helpful to you after reading it. If you want to know more about Zener diodes, please click on our website to browse!


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