Can anyone help me identify a part of an electronic board?

[Dan3345]

This is a fan controller built into my case. There is a copper circle thing. Kind of reminds me of a ferrite core but I know that's not it. I want to know because I'm worried about cable's being exposed to it.

 

If someone could just tell me what it is that would be great. https://sta3-nzxtcorporation.netdna-ssl.com/uploads/product_image/image/193/large_06a374d8aefd13bd.jpg

[Reynard131]

This is a fan controller built into my case. There is a copper circle thing. Kind of reminds me of a ferrite core but I know that's not it. I want to know because I'm worried about cable's being exposed to it.

 

If someone could just tell me what it is that would be great. https://sta3-nzxtcorporation.netdna-ssl.com/uploads/product_image/image/193/large_06a374d8aefd13bd.jpg

 

 

 

It is a fan controller

[Dan3345]

Yeah I knew that.

 

Did you read my post? I asked about a specific part of the fan controller. Sorry, maybe I should have highlighted the copper circle in the top right corner of the fan controller.

Edited April 3, 2016 by Dan3345

[Reynard131]

Yeah I knew that.

 

Did you read my post? I asked about a specific part of the fan controller. Sorry, maybe I should have highlighted the copper circle in the top right corner of the fan controller.

 

 

It is a Ferrite choke that is there to minimize voltage drift for the controller chips.

[Dan3345]

Thank you, that's what I thought it was.

[obobski]

It's an inductor (https://en.wikipedia.org/wiki/Inductor - specifically a toroidal core inductor) - the "L1" gives it away ("L" is standard for labeling inductors in a circuit). It has a thin layer of insulation over the copper windings (https://en.wikipedia.org/wiki/Magnet_wire) but I still wouldn't suggest touching bare wires to it, but it is designed/capable of operating just as-is in the picture. It is part of the circuit that allows the PWM controller to run the 3-pin fans. You can read more about it here:

http://powerelectronics.com/site-files/powerelectronics.com/files/archive/powerelectronics.com/mag/611PET23.pdf

and here:

https://pdfserv.maximintegrated.com/en/an/AN4332.pdf

 

There is no AC filtering going on - the board is taking in DC from your SMPS (which has already rectified the voltage to DC) and then performing DC-DC with an IC (this is how you're varying fan speed). The inductor allows the PWM pulse from the DC-DC to drive the 3-pin fans.

 

As with any inductor (or transformer), it may exhibit "coil whine" which can be really annoying. I know SPCR has some articles on helping to mitigate that but I can't seem to find one to link off-handedly; if its something that's happening for you that'd be where I'd start searching though.

Edited April 4, 2016 by obobski

[Dan3345]

It's an inductor (https://en.wikipedia.org/wiki/Inductor - specifically a toroidal core inductor) - the "L1" gives it away ("L" is standard for labeling inductors in a circuit). It has a thin layer of insulation over the copper windings (https://en.wikipedia.org/wiki/Magnet_wire) but I still wouldn't suggest touching bare wires to it, but it is designed/capable of operating just as-is in the picture. It is part of the circuit that allows the PWM controller to run the 3-pin fans. You can read more about it here:

http://powerelectronics.com/site-files/powerelectronics.com/files/archive/powerelectronics.com/mag/611PET23.pdf

and here:

https://pdfserv.maximintegrated.com/en/an/AN4332.pdf

Wow thanks man! Really helpful information, this was exactly what I was looking for. I thought a ferrite core would usually be insulated, and even if it isn't would actually need to be surrounding an incoming signal, or current.

 

Anyways thanks for the accurate information and schematics. Very useful!

 

Edit: upon reading it sounds like an inductor might be very similar to ferrite core? They both act as chokes, or am I reading that wrong. I know a ferrite core blocks any excess noise on the wire, but it sounds like the inductor blocks AC. So it doesn't block noise?

Edited April 4, 2016 by Dan3345

[obobski]

 

It's an inductor (https://en.wikipedia.org/wiki/Inductor - specifically a toroidal core inductor) - the "L1" gives it away ("L" is standard for labeling inductors in a circuit). It has a thin layer of insulation over the copper windings (https://en.wikipedia.org/wiki/Magnet_wire) but I still wouldn't suggest touching bare wires to it, but it is designed/capable of operating just as-is in the picture. It is part of the circuit that allows the PWM controller to run the 3-pin fans. You can read more about it here:

http://powerelectronics.com/site-files/powerelectronics.com/files/archive/powerelectronics.com/mag/611PET23.pdf

and here:

https://pdfserv.maximintegrated.com/en/an/AN4332.pdf

Wow thanks man! Really helpful information, this was exactly what I was looking for. I thought a ferrite core would usually be insulated, and even if it isn't would actually need to be surrounding an incoming signal, or current.

 

Anyways thanks for the accurate information and schematics. Very useful!

 

 

"Ferrite" gets thrown around a lot (the word comes from the Latin word for iron, ferrum, and it is generally used to describe (unsurprisingly) iron - https://en.wikipedia.org/wiki/Ferrite) - it isn't a "ferrite bead" however (https://en.wikipedia.org/wiki/Ferrite_bead) which are used to filter/reject high frequency noise (usually in/on wiring - you see them a lot on things like laptop power supplies' cords).

 

EDIT to your EDIT:

Ferrite cores/beads are a specific type of inductor, used to suppress or reject high frequency AC noise. The inductor here isn't being used for "noise filtering" but for connecting/bridging the PWM output of the DC-DC controller to the 3-pin fan (which won't work with the PWM pulse).

Edited April 4, 2016 by obobski

[Dan3345]

 

 

It's an inductor (https://en.wikipedia.org/wiki/Inductor - specifically a toroidal core inductor) - the "L1" gives it away ("L" is standard for labeling inductors in a circuit). It has a thin layer of insulation over the copper windings (https://en.wikipedia.org/wiki/Magnet_wire) but I still wouldn't suggest touching bare wires to it, but it is designed/capable of operating just as-is in the picture. It is part of the circuit that allows the PWM controller to run the 3-pin fans. You can read more about it here:

http://powerelectronics.com/site-files/powerelectronics.com/files/archive/powerelectronics.com/mag/611PET23.pdf

and here:

https://pdfserv.maximintegrated.com/en/an/AN4332.pdf

Wow thanks man! Really helpful information, this was exactly what I was looking for. I thought a ferrite core would usually be insulated, and even if it isn't would actually need to be surrounding an incoming signal, or current.

 

Anyways thanks for the accurate information and schematics. Very useful!

 

 

"Ferrite" gets thrown around a lot (the word comes from the Latin word for iron, ferrum, and it is generally used to describe (unsurprisingly) iron - https://en.wikipedia.org/wiki/Ferrite) - it isn't a "ferrite bead" however (https://en.wikipedia.org/wiki/Ferrite_bead) which are used to filter/reject high frequency noise (usually in/on wiring - you see them a lot on things like laptop power supplies' cords).

 

Ah ok, gotcha. Well thanks for clearing that up.

Edited April 4, 2016 by Dan3345