These are part of AC to DC conversion. A half-wave rectifier keeps only the positive part of the signal. A full-wave rectifier also keeps the negative part, but flips it to make it positive too.
Questions tagged [rectifier]
902 questions
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What are the advantages of full wave bridge rectifier with capacitors parallel to diodes?
I found a circuit where in the classical Graetz rectifier capacitors were added in parallel to each diode.
It looked something like this:
After the rectifier itself, there was the usual huge capacitor and regulator and so on.
So why the smaller…
AndrejaKo
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How to convert AC to DC
I am designing a circuit that needs to output 5VDC @ 1A. I'm trying to use a wall transformer to step the voltage down to 12VAC. The next step is the diode bridge and ripple capacitor.
The ripple voltage equation is:
$$V_{ripple} =…
Robert Deml
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AC to DC without transformer. How does this thing work?
I disassembled a Chinese-made flashlight and found they use just capacitors to bring down the voltage instead of a transformer. They are using it to charge small lead-acid battery.
My question is how a capacitor alone can be used to bring 220 V down…
Ryu_hayabusa
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Half-wave diode rectifier - is textbook wrong?
I've noticed that in all resources on diodes and rectifiers, they show the output voltage as the positive half-wave of the input signal. However, that seems wrong.
I understand that there's a voltage drop across the diode, and if the total voltage…
MightyPork
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Power supply - purpose of the capacitor on the side of the transformer before full bridge rectifier
I was wondering if someone can explain the purpose of the capacitor C1141 from the attached picture. I know that C1142 is a filter cap: that much is obvious to me. However, I can't seem to grasp the purpose of C1141. I observed that it is obviously…
Ivan Indir
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Is full wave rectifier better than half wave one?
I am curious if there are practical differences between a DC power supply based on a half wave rectifier or a full wave rectifier.
I mean I have a few small DC power supply units which should give 12V 0.1A each. They all have a transformer…
Al Kepp
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Full-bridge converter rectifier kicks
I'm in the process of building an 8kW isolated DC/DC converter, full-bridge topology.
I'm seeing some interesting phenomena on the diodes. When each diode becomes reverse-biased, a voltage spike appears across the diode, before settling down to the…
Stephen Collings
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Why are rectifiers-inverters used to drive AC motors instead of using the rectified current to drive DC motors?
I understand the advantages of using a rectifier-inverter system to drive an AC motor instead of simply plugging it into mains power, as it allows much better control of its speed and performance; but what I don't understand is: since the original…
Massimo
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Why don't more devices incorporate full-wave rectifiers as reverse polarity protection?
Recently, I was introduced to the idea of using a full-wave rectifier, in order to protect against reverse polarity damage in DC devices.
I hadn't even considered using a rectifier in an already DC circuit, but now that I think about it, why…
Jay Greco
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Is a half-wave rectifier particularly hard on a transformer?
In the book Practical Electronics for Inventors, 3rd Ed., the authors recommend against using half-wave rectifiers because they're inefficient and cause "...the core to become polarized and to saturate in one direction." (Page 395.) Is this a valid…
Phil
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if a standard three-phase 400V AC connection is rectified what DC voltage comes out of it?
If a standard (in Europe and a large part of the world except North America and Japan) three-phase 400V AC (three lines having 230V RMS voltage if measured to neutral each) mains supply is rectified with a standard 6-diode rectifier like this:
What…
ria
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Will Stressing a Lamp Filament with AC, DC and/or Relay chatter change its lifespan?
I am building a device that shortens the lifespan of an old style "edison" bulb with an extra long filament as a kind of arbitrary timer.
I am planning to "stress" it (not immediately explode it or anything) by rectifying the current using an…
Oliver Kellow
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Serial capacitors in electronic ballast of a fluorescent lamp
Recently I repaired one broken electronic ballast of a linear 30W fluorescent lamp. Now it seems to be working as expected, but I had to make some changes to it and I'd like to ask if you see any hidden problems I can get into due to those…
Al Kepp
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Why does this bridge rectifier claim to have no diode forward voltage drop?
I was, "OK, this is feasible," but then I traced how it worked and it simply blocked current through drain and source when a P and N pair are reverse biased. When the other P and N pair are forward biased current flows through forward fiodes, then…
kozner
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How does this rectifier work?
In a car battery charger, I found a strange rectifier. Can someone explain to me how does it work?
Here I have a transformer which is unmarked. By measuring resistance between its output terminals, I determined that the plus cable is connected to…
AndrejaKo
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