# Bridge rectifier

#### scam313

Joined Jul 19, 2022
44
In a DC circuit With a bridge rectifier how does current to an LED flow both ways.

#### scam313

Joined Jul 19, 2022
44
I know it's a DC pulse but does it allow for LEDs to light up from left to right and then from right to left

#### Dodgydave

Joined Jun 22, 2012
11,318
A bridge rectifier converts AC to DC voltage, so an led will work only one way with the correct polarity ,.

Joined Jul 18, 2013
28,769
..and a 1ph bridge rectifier just provides pulsing DC . IOW all in one direction, it does not reverse .

#### dl324

Joined Mar 30, 2015
17,008
In a DC circuit With a bridge rectifier how does current to an LED flow both ways.
It would be helpful if you posted a schematic.

#### ElectricSpidey

Joined Dec 2, 2017
2,837
In a DC circuit With a bridge rectifier how does current to an LED flow both ways.
It flows one way thru two of the diodes, then the other way thru the other two diodes.

#### scam313

Joined Jul 19, 2022
44
Ignore some of the components and take the IC as a rectifier going to the LEDs and current limit resistor. With a bridge switching at a high frequency won't the LEDs be able to illuminate with the current flowing in either direction?

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#### crutschow

Joined Mar 14, 2008
34,692
In a DC circuit With a bridge rectifier how does current to an LED flow both ways.
It doesn't in the LED.
The bridge converts the two-current to one-way through the LED.

Here's a Falstad simulation that shows the current through a bridge rectifier (replace the 100Ω load with the LED).

#### scam313

Joined Jul 19, 2022
44
It doesn't in the LED.
The bridge converts the two-current to one-way through the LED.

Yes the polarity of the LED does not change and the current will flow only one way. Correct me if I am wrong but when the sine wave goes low or negative the rectifier switches the current flow to the anode thus still allowing the LED to illuminate.

#### crutschow

Joined Mar 14, 2008
34,692
Correct me if I am wrong but when the sine wave goes low or negative the rectifier switches the current flow to the anode thus still allowing the LED to illuminate.
That's an odd way of putting it.
The rectifier simply blocks the flow in the reverse direction, so only the diodes that have forward voltage, conduct, and that means the current is always flowing from anode to cathode in the LED.

#### MisterBill2

Joined Jan 23, 2018
19,009
The TS needs to return to the basic electricity course and learn how a diode functions. A diode function is to conduct current in one direction ONLY, when the voltage in that direction exceeds some small amount. When the voltage is in the opposite direction the current does not flow. It really is that simple.
How is it that one claiming to be an electrical engineer does not have a clear grasp of that basic function???? That is a puzzle to me.

#### scam313

Joined Jul 19, 2022
44
The TS needs to return to the basic electricity course and learn how a diode functions. A diode function is to conduct current in one direction ONLY, when the voltage in that direction exceeds some small amount. When the voltage is in the opposite direction the current does not flow. It really is that simple.
How is it that one claiming to be an electrical engineer does not have a clear grasp of that basic function???? That is a puzzle to me.
Student that works in manufacturing, I just put that thinking that alerts to my email would be geared to the field.

#### MisterBill2

Joined Jan 23, 2018
19,009
Student that works in manufacturing, I just put that thinking that alerts to my email would be geared to the field.
"Information" says electrical engineer. n EE student, possibly???