Wikipedia:Reference desk/Archives/Science/2022 January 28

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January 28[edit]

Why characteristics graphs of p–n junction and Zener diode are similiar?[edit]

See characteristics graphs of p–n junction : click here

See characteristics graphs of Zener diode : click here Rizosome (talk) 01:49, 28 January 2022 (UTC)[reply]

Because they are the same! See the first line of Zener diode: "A Zener diode is a special type of diode designed to reliably allow current to flow "backwards" when a certain set reverse voltage, known as the Zener voltage, is reached." You can use any diode as a zenner but: (1) the Zener voltage will not be accurate, and (2) you may well destroy the diode doing so unless you are very careful. The difference is in the fine details of the physical structure. That's why the symbols are nearly identical, but with the two little "wings" which change the bar into a "Z" for Zener (or it is sometimes said it reflects the characteristics). Martin of Sheffield (talk) 09:52, 28 January 2022 (UTC)[reply]
(ec) Their current/voltage chracteristics are similar because P-N junction diodes, whether specified as rectifiers or for a specific reverse breakdown characteristic, are all similarly constructed. There is a wide spread of characteristics in mass produced diodes and individual diodes are selected to meet specification from this continuum. So a diode selected as a rectifier such as 1N4001 must satisfy a published forward current-voltage specification. It will also have a reverse breakdown voltage, but as long as it is more than the guaranteed value (50V) for this diode, its actual value is neither important nor guaranteed. Conversely diodes intended for use as zener diodes are produced with heavier doping of the P-N junction that encourages a low breakdown voltage (especially values below 5.6V) but they must be tightly selected from production for exact reverse voltages e.g. 4.7V for type 1N4624. Philvoids (talk) 10:45, 28 January 2022 (UTC)[reply]

I got the answer: Their current/voltage chracteristics are similar because P-N junction diodes, whether specified as rectifiers or for a specific reverse breakdown characteristic, are all similarly constructed. Rizosome (talk) 07:51, 29 January 2022 (UTC)[reply]

Resolved