Does Putting Diodes in Parallel Lower Their Voltage Drop?

Part 1: The Diode.

[An assortment of diodes: 1N4003 on top, 1N4002 in the middle, 1N914 on bottom.]

Intro

I'm going to assume that you (the reader) already have an at least basic understanding of the purpose of regular diodes, how to find the anode and cathode on a real diode, how to use them, and how to read a schematic.
The purpose of this article is to display my test results in a friendly, easy to read format (with extra info on diodes thrown in for free)

It all started when I was wondering if I could use ten or so cheap 1N914 Diodes in parallel to lower their voltage drop to the point that they would be useful for more than just gobbling precious power up.

[1N914/1N4148's are notorious for their voltage drop of 0.20-volts or so. I bought 100 from allelectronics.com here, but those are currently sold out, so get a similar diode here. You could also get a 1N14148, also a generic, cheap diode.]

The reason for this is that I want to save my (relatively) expensive schottky's (good quality. 0.002Vdrop, 1AMP, 40V, AKA 1N5819, gettable here.) for other, more important stuff.

You can also get other kinds of cheap diodes here, but make sure you get the right kind of diode.

Info

But first, Some information about diodes. "What?!?" you say, "Don't turn this into a research paper!"
I'm doing this to keep us all on the same page, so bear with me. It's more trouble to write an HTML document than it is to read one.
Deal with it.

The Wikipedia article on Diodes saves me a lot of trouble.
At the very least, skim it before continuing.
The parts of the article that concerns us are the paragraphs about the regular p-n, power conversion, and the schottky, but the rest of the article is also jam-packed with useful information.

Anyway, here is a list of terminology that will be used at some point or another in this article:

{diode terminolgy wiki...where?}

Forward Voltage Drop:
This is what the article is all about;
how much voltage is lost when the diode is forward biased (power going through it in a forwardly direction). See: Wiki: Voltage drop
Maximum Forward Current:
The maximum amount of current that can go through a diode (forward) without damaging it. Generally, the bigger the diode is physically, the more current it can handle, but be cautious when buying diodes.
When you look at the datasheet (a big table of need-to-know information as to the properties and limits of the diode, see:Wiki-Datasheet.) of diodes, and transisors, don't be fooled by the maximum current limits listed. More often than not, they are assuming that the diode has a large heat sink(chunk of metal that whisks away heat, see: Heatsink), and that the air is a certain temperature (25 degrees Celsius, sic), etc.
Usually, the practical current limit is much lower than what's on the datasheets, unless....
Reverse current leakage:
How much current goes through the diode when the voltage is going backwards. Most diodes leak only a negligible amount (ideal diodes leak none), but David Cook of Robotroom.com said somewhere that 1N5817 schottkys (SHOT-kee) seem to be more leaky than other regular diodes....
EXCEPTION: Photodiodes in reverse bias mode (as opposed to forward bias, see Wiki: Biasing) allow differing amounts of current to leak based on light level.
Maximum Forward voltage:
The maximum amount of (forward) voltage that the diode can handle before being destroyed. Most (cheap) diodes have forward voltage maximums anywhere from 50-to-500 Volts, so this is not usually a problem to worry about.
EXEPTION: Some diodes out there somewhere may have a forward voltage limiting feature, but I have not heard of these... Somebody invent them so I can put it here, making this article more bigger, and impressive!
Maximum Reverse Voltage:
The highest (backward) voltage that the diode can block before it breaks, letting power go through it, destroying the diode(bad), similar to a (water holding) dam.
When shopping for diodes, the maximum Reverse voltage is called PIV, which stands for Peak Inverse Voltage, see: PIV on wikipedia
EXCEPTION: Zener (ZEE-nehr, see: Wiki:Zener) diodes are designed to "break" at a predictable voltage(For higher voltage triggers, use Avalanche diodes). When using these, be careful, as too much power will fry it.
These are extremely useful for Solar Engines (SE's), where a relaxation oscillator requires a specific trip point.
More information on Zener SE's is here,
and, more info on SE's in general is here: here:, and how to build them here.
Zeners are also useful for voltage regulation. Just Google "schematic, Zener voltage regulator", but without the quotation marks. In fact, since I know that most of y'all will be too lazy to do it, I did it for you, so that all you have to do is click on the following link: the following link:
Forward Breakover Voltage:
The minimum amount of voltage required to keep the diode conducting. If the voltage gets below this point, the diode stops conducting. Usually, this threshold is low enough that you don't need to worry about it.
If you need to keep a small signal from getting too high, use a diode with a high forward breakover threshold. The idea is that when the signal is withing safe limits, the diode doesn't conduct, but when it gets too high, the diode conducts, effectively shorting out the signal until it's lower again.
This technique (called voltage clipping, methinks, see: Clipping [signal processing] or Clipping [Audio]) is mostly used when interfacing to a microphone-input port on a computer to keep from frying it.
{Fast recovery diodes not covered here. See the wikipedia article on them.}
Full-wave Bridge Rectifier:
Actually four diodes in one package meant to change AC to DC easily, and cost-effectively.
In fact, using this, you can steal electrical power from the phone company (most likely illegal, but you can see it here. Link provided only for educational purposes only. Not responsible for damages that may occur.)
Also good for other uses, but it does not concern this article (mostly).

Article continued in Part 2.

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