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One problem I see is you are showing a polarized capacitor and applying an AC signal in your drawing. The capacitor will be short lived and with enough AC will explode. "Most electrolytic capacitors are polarized and require one of the electrodes to be positive relative to the other; they may catastrophically fail if voltage is reversed". Yes, you can use an electrolytic capacitor with DC. Polarized electrolytic capacitors can only be used with DC.
Actually I was wrong in a way. Because electrolytic capacitor is in fact used with DC. For AC, there are special kind of electrolytic capacitors.
I have read that 'regular' capacitor can store very little amount of charge in comparison to a electrolytic capacitor and that's the reason they are preferred over 'regular' or 'normal' capacitors. Is this really so? Please let me know. Thank you.
I have read that 'regular' capacitor can store very little amount of charge in comparison to a electrolytic capacitor and that's the reason they are preferred over 'regular' or 'normal' capacitors. Is this really so? Please let me know. Thank you.
All that means is that electrolytics are, generally speaking, much larger than other types of capacitors (ceramic, plastic (polyester, etc.), tantalum, etc.). The larger the capacitor (in farads), the more "charge" it can store. So yes, electrolytics store more charge just because they're bigger. They're not necessarily "preferred" over other types (in fact, the opposite is more true, as electrolytics also tend to fail more than other capacitor types): it's just that if you need a 1000µF capacitor, you're not going to be able to get it with a ceramic cap.
There are AC electrolytics that have the oxide/paste coating on both sides of the aluminum foil. They are used for starting up an induction motor and some used in speaker frequency crossover filters. They will quickly blow out if run with large continuous AC current.
Electrolytics have a large amount of capacitance for a given area (smaller physical size) but have a relatively high equivalent series resistance. Because of the higher ESR they do not tolerate high ripple current (a lot of charging and discharging current) as the high ripple current along with the ESR will cause internal heating that will dry out the fluid paste between the electrodes or cause an expansion bloating of the capacitor container to point of failure.
Large grid frequency transformer based power supplies have given way to modern high frequency switching power supplies which are now cheaper to make and smaller in size. One issue with a lot of the switching power supply designs is their electrolytic filter caps are being subjected to high ripple currents that exceed the capacitors manufacturers rating resulting in high failure rates. LCD TV's and computer monitor power supplies often have this issue.
But isnt that what this forum is all about, electronic and related questions? Why not ask here...
Anyway...
Electrolytic caps are used for coupling AC signals too. Even though it is AC, it works because the DC potential at the positive terminal of the cap is always held at a higher voltage than the negative terminal of the cap. The AC can pass through while the DC requirement of the cap is met.
I offer my thanks for all the help, carbonzit, RCinFLA, MrAl.
Would you please help me a bit more?
1: I think in the linked image, the caps on the left side of the red 'line' are electrolytics, and on the right regular/normal ones, please correct me if I'm wrong: https://img641.imageshack.us/img641/7758/capshn.jpg
I offer my thanks for all the help, carbonzit, RCinFLA, MrAl.
Would you please help me a bit more?
1: I think in the linked image, the caps on the left side of the red 'line' are electrolytics, and on the right regular/normal ones, please correct me if I'm wrong: https://img641.imageshack.us/img641/7758/capshn.jpg
As you might guess, an Integrated Circuit is a lot of components (for the most part just semiconductors--transistors and diodes--and resistors) made in an "integrated" package. ICs are made on a single piece of silicon, called a substrate, with the various components laid down as overlays and etchings of layers of different materials. A fascinating manufacturing process. Tons of information out there on the web; just look it up.
So instead of just a single transistor, an IC might contain dozens, hundreds, thousands and even millions of transistors, plus other parts.
I was watching this video on UTube and thought it might be useful to someone like me who stumble onto this thread:
I didn't know that ICs also contain resistors and capacitors; I thought they contains in themselves only semiconductor components - i.e. diodes and transistors.
I didn't know that ICs also contain resistors and capacitors; I thought they contains in themselves only semiconductor components - i.e. diodes and transistors.
Not so much capacitors: those are seldom incorporated into ICs, and always are low values. Likewise inductors (does anyone know of any chips that actually contain an inductor?) Mostly Qs, Ds and Rs.
Not so much capacitors: those are seldom incorporated into ICs, and always are low values. Likewise inductors (does anyone know of any chips that actually contain an inductor?) Mostly Qs, Ds and Rs[\b].
2: Computer processors are also ICs. In the video in my previous post the presenter compares the size of an IC and its equilant circuit in 'normal' form. How large would an equivalent circuit of a modern day processor (IC), let's say Intel P4, be?
3: Almost every computer processor has its Hz rating. Nowadays processors come in GHz ratings. Wht does this frequency rating mean? A computer works in digital mode, i.e. on and off state. So, does this Hz rating tell how many times an invidual transistor can turn on and off without damaging itself? I don't want to get into technical details of this. So, please it involves some very technical details then you can skip this query. Thanks.
2: Computer processors are also ICs. In the video in my previous post the presenter compares the size of an IC and its equilant circuit in 'normal' form. How large would an equivalent circuit of a modern day processor (IC), let's say Intel P4, be?
The P4 contains about 55 million transistors. (Reference here.)
3: Almost every computer processor has its Hz rating. Nowadays processors come in GHz ratings. Wht does this frequency rating mean? A computer works in digital mode, i.e. on and off state. So, does this Hz rating tell how many times an invidual transistor can turn on and off without damaging itself? I don't want to get into technical details of this. So, please it involves some very technical details then you can skip this query. Thanks.
The frequency rating is just what you'd think it is: the maximum frequency that the chip as a whole can operate at.
It's not so much a matter of safety as it is of the speed limits of the chip's circuitry. At gigahertz frequencies, it's operating in the radio-frequency (RF) band, where electronic devices reach their limit as to how fast they can switch on and off. Unlike RF devices, though, microprocessors operate entirely on square waves (at least ideally), so the gates and other devices in the chip are mostly transitioning between two states, on and off. (Even this isn't strictly true, as some circuits, like Schmitt triggers, have a range of voltages which they operate within.) But for a first-order explanation, you can look at the chip as operating entirely in the digital realm, using only square waves.
When the speed limit of a circuit is exceeded, it starts behaving unreliably, which obviously is unacceptable in a digital computer. So chips like the P4 are specced to operate below their absolute upper speed limit so that there won't be any "lost bits" or other glitches.
The P4 contains about 55 million transistors. (Reference here.)
The frequency rating is just what you'd think it is: the maximum frequency that the chip as a whole can operate at.
It's not so much a matter of safety as it is of the speed limits of the chip's circuitry. At gigahertz frequencies, it's operating in the radio-frequency (RF) band, where electronic devices reach their limit as to how fast they can switch on and off. Unlike RF devices, though, microprocessors operate entirely on square waves (at least ideally), so the gates and other devices in the chip are mostly transitioning between two states, on and off. (Even this isn't strictly true, as some circuits, like Schmitt triggers, have a range of voltages which they operate within.) But for a first-order explanation, you can look at the chip as operating entirely in the digital realm, using only square waves.
When the speed limit of a circuit is exceeded, it starts behaving unreliably, which obviously is unacceptable in a digital computer. So chips like the P4 are specced to operate below their absolute upper speed limit so that there won't be any "lost bits" or other glitches.
Suppose a modern day processor (IC) takes an area of 3 sq. inch, then how much area or space an equivalent circuit of that processor had taken if it were made before IC evolution? A room? Please watch the video in the post #11 from 3.00 onward.
2: I think I should also rephrase the query about the frequency rating, MHz, GHz, etc. In my practical life I have never seen a square wave. I'm very naive with this technical stuff. These days I'm trying to grasp the bigger picture of how these things work without getting into very technical details. What I understand so far is that the frequency rating only tell the maximum rate at which transistors in the chip can work. If the frequency is 20 Hz then that would mean that a transistor could turn on and off 20 times a second. And if we try to run transistor at a frequency larger than the specified then it would get damaged. Do I make any sense? I don't know any exact search terms to search this topic on UTube, could you please help?
3: In the linked diagram I have tried to show that how, in my opinion, an IC is made. It's only a very, very 'rough' attempt. Please let me know if I have it right. Thanks.
My bad; I missed that question (which is a good one). The answer? I don't know; huge, for sure. Just picture a machine made of 55 million discrete transistors, plus all the other stuff needed. Now, it probably wouldn't be as big as the really early computers that used relays or vacuum tubes--those would be monstrously large--but it could easily fill a room.
Another consequence of discrete construction is that it would use enormous amounts of power compared to the chip.
2: I think I should also rephrase the query about the frequency rating, MHz, GHz, etc. In my practical life I have never seen a square wave.
Well, neither have I, nor has anybody else. I have, however, seen representations of square waves, like on an oscilloscope CRT.
I'm curious, though: why do you say you've never seen a square wave? Are you not very experienced with electronics? or have you only dealt with so-called analog circuits? (some of which may also use square waves)
And if we try to run transistor at a frequency larger than the specified then it would get damaged.
Where do you get this idea from? I suppose it's faintly possible that a transistor could be damaged at a higher frequency than what it's spec'ed for, but it would take a lot of power, probably over its maximum power rating.
It's not that circuits get damaged at frequencies higher than they're designed for: it's just that they cannot respond quickly enough to things like short pulses and repetitive pulses. They just don't work right at too high a frequency.
3: In the linked diagram I have tried to show that how, in my opinion, an IC is made. It's only a very, very 'rough' attempt. Please let me know if I have it right.
Can't read what you wrote in that picture, but in any case, why guess? There plenty of explanations of how ICs are made out there in web-land, like this one.
I'm very inexperienced in this stuff. I believe just two months ago you were helping me to learn mesh analysis etc. I have played around with o-scope sometimes but not very often. In my previous post what I really meant was that I don't understand how square wave works because I haven't even seen on an o-scope in real life and I'm sure in nature no such thing exists as a square wave. Well you can have sinusoidal wave in real life; water ripples roughly correspond to sinusoidal waves.
I have increased the resolution of the image. Please have a look again. Thank you.
In my previous post what I really meant was that I don't understand how square wave works because I haven't even seen on an o-scope in real life and I'm sure in nature no such thing exists as a square wave.
You'd be surprised: lots of wave phenomena exist in nature. The cricket emits a sawtooth wave, much like a violin string being bowed. Systems that oscillate between two extreme states may well exhibit square-wave response. Lots of stuff in nature is non-sinusoidal.
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