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How to choose a diode? Fast edges, minimal overshooting and ringing during a step inp

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Newbie level 4
Mar 12, 2012
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I want to choose a diode for a circuit where the edges are very fast (1-5ns range), high-ish voltage (+/- 100V) and i want as little overshoot and ringing as possible during a step input, where it settles very fast.

How do i go about choosing the correct diode? I've tried looking at datasheets for diodes and they seem to offer very information. I understand the power and temperature side of it. Obviously i want something with minimal inductance and capacitance, in a perfect world a device that doesn't have a complex impedance would be ideal. The question is, how do i find my perfect device?

My question also goes for zener diodes as well? Pretty much the same as a diode, 1-5ns edges, +/-20V and as little overshoot and ringing as possible during a step input.



a diode on it´s own makes no sense. There will be other parts that give the diode the desired fuction. Only with the surrounding circuit we can calculate the values.
--> Show us your schematic.

Zener diodes usually have a lot of capacitance...


Indeed a circuit with just a diode does not make any sense at all but i didn't think my question requires my circuit since i've specified what i'm looking for and i think that i need to drill down on the parasitics of both the diode and zener diode that i'm already using. In essence the diode is connected to a resistive load in series from the drain of a MOSFET. The zener diode with a resistor is tying the gate to source of the MOSFET. The MOSFET is driven via an AC coupling capacitor from a MOSFET driver.

I used to think that fast and Ultrafast were buzz words that certain manufacturers just used as an advertisement gimmick in an attempt to gain your purchase since i couldn't see any differences in the datasheets. Quite clearly there are things that manufacturers don't know how to accurately characterise or choose to leave out. I saw this image in a book today which makes me think that i'm actually wrong. When i checked the datasheets for all three of these diodes i couldn't see anything that would give me a hint of what to expect.
**broken link removed**

Generally the fastest type general purpose switching diodes are Schottky types although there may not be many that are rated at 100V.

I'm with KlausST. The question is pointless without a specification of connected circuit impedances and driving waveforms.

If you possibly intended to post a schematic, there's no valid link.

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