Qxi.xli
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my teacher said that a diode can be used to correct circuits to turn a A.C current to a D.C current, but thinking logically how would that be possible? of course, it would only allow current to flow in one direction, but wouldn't the current be broken up, if that makes sense?

thanks
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Joinedup
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Yeah with a single diode you get pulsating dc... Which is still a type of dc because the current never changes direction.
If you drew a graph with time on the x axis (or used an oscilloscope) it'd look like sinewave with the bottom missing (or the top missing if the diode was pointing the other way)
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Qxi.xli
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(Original post by Joinedup)
Yeah with a single diode you get pulsating dc... Which is still a type of dc because the current never changes direction.
If you drew a graph with time on the x axis (or used an oscilloscope) it'd look like sinewave with the bottom missing (or the top missing if the diode was pointing the other way)
oh i see thanks x
so why is this a use then? if you get a pulsating current :/
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Joinedup
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(Original post by vix.xvi)
oh i see thanks x
so why is this a use then? if you get a pulsating current :/
Well youd typically use it in low power, low cost applications that don't mind pulsations but do need it to be dc...

Small lead acid battery charger
Small electroplating cell
Negative ion generator
50hz strobe light that oldies used to use with a tachymeter disk so they could get their vinyl records playing at the right speed.

Single diode is pretty inefficient so for higher power applications the 4 diode bridge rectifier is preferable.
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username3928322
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This can be done via something called a "full bridge rectifier", also known as a "bridge" and as mentioned the sine wave output with the bottom half missing can be smoothed out using capacitors and the more capacitance you add the smoother it will be. This as mentioned by Joinedup is used for applications that require a constant current rather than pulsations. And down below is quite possibly one of the worst diagrams made by yours truly on paint which took about 30 seconds. But the red line is the output with a capacitor and the pulses are the original output.

Name:  Screenshot 2021-01-20 163758.png
Views: 7
Size:  26.5 KB
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Qxi.xli
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(Original post by AnotherRandom)
This can be done via something called a "full bridge rectifier", also known as a "bridge" and as mentioned the sine wave output with the bottom half missing can be smoothed out using capacitors and the more capacitance you add the smoother it will be. This as mentioned by Joinedup is used for applications that require a constant current rather than pulsations. And down below is quite possibly one of the worst diagrams made by yours truly on paint which took about 30 seconds. But the red line is the output with a capacitor and the pulses are the original output.

Name:  Screenshot 2021-01-20 163758.png
Views: 7
Size:  26.5 KB
Haha tysm.
The diagram looks great btw, very detailed 😂
(Original post by Joinedup)
Well youd typically use it in low power, low cost applications that don't mind pulsations but do need it to be dc...

Small lead acid battery charger
Small electroplating cell
Negative ion generator
50hz strobe light that oldies used to use with a tachymeter disk so they could get their vinyl records playing at the right speed.

Single diode is pretty inefficient so for higher power applications the 4 diode bridge rectifier is preferable.
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Joinedup
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(Original post by AnotherRandom)
"full bridge rectifier"
Do you watch electroboom videos too?

Image
:top:
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username3928322
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(Original post by Joinedup)
Do you watch electroboom videos too?

Image
:top:
As an EE student of course I’d be a fool not too
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