Zener Planar Diode ZPD

[gmc]

I have a faulty ZPD 4V3 diode. According to the data sheet it's a zener planar diode which is a term I've not heard of before (planar)

Data sheet here:
https://www.tme.eu/en/details/zpd4.3-dio/tht-zener-diodes/diotec-semiconductor/zpd4-3/

What's the difference between this a normal zener diode. Can I use a BZX55C4V3 for example it's place?

https://www.vishay.com/docs/85604/bzx55.pdf

[T3sl4co1l]

All diodes are planar; it might've been a term of note in the early years, perhaps it's a very old product line?

Looks completely identical to the BZX series yes.

Tim

[gmc]

Thanks. Learnt something new.

It's a diode from the early 80's so that would explain the terminology.

[DavidKo]

The name was used to distinguish them from point contact diodes. Today 99% of diodes are the one produced by planar technology.

[T3sl4co1l]

I would expect it's a lot higher than that... but once you get into the question of "how many nines?", clearly there's a lot, regardless.

Tim

[gamalot]

When I was a kid, the most common one in China was point-contact germanium diode 2AP9.