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Why is it PNP instead of PPN for transistors

ratstar

Aug 20, 2018
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Thanks.
Confusing as heck, but I have to learn it, if I want to learn about parasitic effects, because I want really fast logic.
Reading books can help, but I what I need to do is just get some leds and inductors and check it out myself, I'm really good at capacitors just doing that, just need to do the same with inductors, and then I could poke flaws in all the videos in the internet cause I think they are all WRONG!!
 

Audioguru

Sep 24, 2016
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Coil and magnet speakers are made to play AC sounds. You are probably frying them with DC.
Many You Tube videos about electronics are completely wrong and are made by kids who get paid by You Tube each time somebody views an ad before the video.
 

hevans1944

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Many You Tube videos about electronics are completely wrong
This statement about You Tube videos actually applies to a LOT of stuff posted on the Internet, not just electronics. And it, of course, also applies to other communications media, such as the printed word on paper or as read on a video monitor. It is becoming really hard to determine what to believe, or who to trust, in this century. Okay, it's always been hard to find the truth in any century, but the search for truth is an interesting endeavor in itself.

I have to learn it, if I want to learn about parasitic effects, because I want really fast logic.
If you want to learn about reeeealy faaaast logic, you need to learn about quantum computing and qubits. Folks who are learning how to build computers with qubits probably think it might be able to answer questions even before someone asks them. This could lead to AI smarter than God, unless He got there first. Just kidding. No one has built a practical qubit-based computer yet.

Problem is, currently you need to cool the "circuits" down close to absolute zero Kelvin before anything begins to work. Not exactly a home-brew project, unless you happen to have an ultra-high vacuum system (for heat insulation), a gold-plated whatsis for the electronics, plus a few PhDs to keep everything running. Lots of images of the experimental hardware can be seen here.
Or, just Google "quantum computer images".

Parasitic effects were one of the many reasons that SPICE software modeling was invented during the initial development of integrated circuits. Back in the day, it was very expensive to perform the artwork layouts necessary to produce mass quantities of integrated circuits. Even with the artwork in hand, it could take weeks to process the wafers and build up the integrated circuit, layer by layer. Without some means to simulate the final product with a computer program, it could (and did) take months to go from concept to something that was tested, reliable, and could be sold in million-lot quantities for just of few pennies per device. Of course the "price per chip" didn't come down into the pennies range until late in the 20th century, after almost fifty years of experience and expanding competition.

Logic speed advanced with each generation of new logic devices. Resistor-Transistor-Logic (RTL) was soon replaced by Diode-Transistor-Logic (DTL) which yielded to Transistor-Transistor-Logic (TTL) in the 1960s. Then CMOS came along to sacrifice speed for low power consumption while Emitter-Coupled-Logic (ECL) hung in there as the speed champion for a long time. Eventually CMOS speeds matched TTL speeds, but by then discrete logic circuits were being replaced with chips containing more advanced circuitry, all on a single chip. Initially, there were some "false starts" on the way to the goal of a system-on-a-chip: early processors required a boatload of "glue" integrated circuits before anything useful could be accomplished.

And that brings us to about the beginning of the 21st century. Today, ICs can pack billions of transistors on each chip, and the dimensions of "features" such as transistors, diodes, resistors and conductors has shrunk to sub-micrometer levels, so small that soft x-rays are required to expose the photo-resist masks used to make the ICs. This is where you want to be, now and in the foreseeable future, if you want to get involved with the fastest logic available using electronics. The human brain is still the most complex, and the fastest, "computer" currently available but the input/output channels nature provided are too slow to take advantage of the processing power available. Plus, no one really knows how the human brain works or how to replace or repair a defective one. So, science must get along with the current Mark I model until someone figures out how to build a qubit computer to replace it. When, not if, that day finally comes, the first sentient artificial intelligence computer may appear, or so science fiction authors have long speculated.
 

ratstar

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I didnt think of the fact that "vacuumization" can help with heat transduction loss! thanks.

I have a crazy idea, about "energy retainment" involving vacuum interrupters (for less loss in a spark gap, but I wonder if its soo lossy as hell anyway.) and big low resistance coils where being above 1 milliohm for the whole circuit is not what you need to be, and super cooling could help there to bring the resistance down.

If your transfering energy from capacitor to capacitor, or inductor to capacitor to inductor, theres alot of energy loss just from getting from a to b.

I just went to shop and got 1 milli-henries worth of inductors (4 of them in series), I wired them together and it is 3.6 ohms already!!! and I need to be a milliohm, and that is COPPER, the best conductor you can use!!! So I might have to put a pause on this idea and just do things more resistively/damped for now.

I imagine because the copper must be thick to do it, inductors can get pretty expensive and large sized (low resistance inductors) even just taking it account the raw copper mass required to even just constituate them.

You know how home stereo gear is "8 ohm" thats already 8 ohms too much over the milliohm I need, so I cant even attach a speaker to it, its so frugal.
 
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Audioguru

Sep 24, 2016
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A speaker with an 8 ohms impedance usually has a 6 or 7 ohm resistance.
The leads of your ohm-meter are probably the 1 ohms difference. Short the probes together to measure the resistance of the leads.

Here is a graph of the impedance vs frequency of a speaker. The impedance is a peak at the mechanical resonance and rises as the frequency rises because of its inductance:
 

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hevans1944

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I didnt think of the fact that "vacuumization" can help with heat transduction loss! thanks. ...
Double-walled glass flasks, with a good vacuum between silvered outer and inner walls were invented in the 19th century by James Dewar. Glass encloses one end of the flask, and the other end was usually loosely closed with a cork or rubber stopper. Dewar's invention was globally popularized by the Thermos brand vacuum-insulated bottle.

... If your transfering energy from capacitor to capacitor, or inductor to capacitor to inductor, theres alot of energy loss just from getting from a to b.
Moving electrical energy from "a to b" does result in some loss of energy (as heat) because of wire resistance, but using properly sized conductors minimizes the loss.

... COPPER, the best conductor you can use!!! ...
No, silver is the best conductor... unless you use superconductors, which have zero resistance. Most home experimenters cannot afford to use superconductor technology. For transferring large amounts of power, aluminum-clad steel cable is used because aluminum is so much cheaper than copper or silver. It appears to me that you need to "brush up" on how electricity works. And maybe thermodynamics, too.
 

Ratch

Mar 10, 2013
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It can tolerate some reverse current but
The N (base) of a biased PNP transistor is more negative that the other P terminals.

That is why its labeled that way.

The letters don't mean how to hook it up + or -, it's indicating the junction inside the component.

A BJT works on current flow which is dependant on polarity. Thinking of just polarity can confuse matters.

The PNP allows current to flow from the Emitter to the collector when a small current flows out of the base when its more negative than the emitter.
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Be careful what you are saying Fiber Magee. A BJT is a transconductance device (voltage controls current), not a current controls current device. It works the same as a FET or a vacuum tube. The current present in the base circuits is waste current that does not control the collector current, but happens to be be have a a ratio to the collector current. That ratio is called "beta". In a PNP BJT, a negative signal voltage will control the collector current. The charge flow is from the collector to the emitter.

Semiconductors are labeled N-types because they are doped with elements containing (N)umerous electrons. Other semiconductors are labeled P-types because they are doped with elements containing a (P)aucity of electrons.

Ratch
 

Nanren888

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superconductors
Interesting that those two go together too.

The corridor below me, here, always sees large "dewer"s metal Dewer bottles (Like large grey metal egg-shaped bubbles in cradles to make tipping them easy) of liquid nitrogen used in the HTS High temperature Superconductor work.
Superconductors currents are usually high, so fields build up, so they don't necessarily like the current to change quickly. An dther's all that liquid nitrogen to supply.
Maybe stick with silver, copper or aluminium :)
 

hevans1944

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HTS sorta reminds me of man-made nuclear fusion: widespread commercial application is always just fifty years from now. And my barber shop has a sign that advertises FREE BEER... tomorrow.

There is no doubt that materials exist that exhibit superconductivity at liquid nitrogen boiling temperatures (about 77K) as well as liquid helium boiling temperatures (a few degrees Kelvin), but the HTS holy grail is a superconductor that operates at nearly normal room temperature (about 300K) and does not require cryogenic liquids. Maybe soon, maybe not so soon. Meanwhile, use water-cooled copper or aluminum tubing until a break-through technology appears.

Controlled nuclear fusion for generating electrical power seems even less likely in this century. But, we already have a large gravity-contained nuclear fusion reactor running continuously in orbit a safe 93,000,000 miles above our heads. it provides approximately one kilowatt per square meter of radiant energy over most of the surface of the Earth. Suck on some of that until something better comes along. Or gather some of the solar wind and use that for power. Plenty of energy is available in Outer Space, if we can figure out a way to avoid becoming crispy critters while learning to harvest and put it to use.
 

bertus

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Hello,

@ratstar , A PPN device would not exist. The PP junction can be seen as one, so a PN device is left, wich is a simple diode.

Bertus
 

bertus

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Hello,

Helium ans nitogen are not flamable.
The helium is used to cool the magnet, the nitogen is used as isolation.

Bertus
 

ratstar

Aug 20, 2018
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Shit. Werent the zepplins in world war 2 full of helium? and they explode?
 

Martaine2005

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Shit. Werent the zepplins in world war 2 full of helium? and they explode?
That would be hydrogen. The main reason for the catastrophic meltdown in midair was the ‘dope’ they painted the fuselage material with called Thermite.

Martin
 
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