Inductor placement

Thread Starter

muslii

Joined May 4, 2022
4
I recently burnt an inductor in the flight controller of my fpv drone. I bought a new one to replace it with, however, I could not find any SMD ones that would fit so I bought a THT one (with the same inductance). But because of its size, it is difficult to find a place for it. The only way I found was to place it like in the picture, and it seems to work. I only have a basic knowledge of electronics, but I was wondering if the long legs could potentially be a problem? I think the inductor is a part of a dc to dc converter used for some peripherals that don't use a lot of power, but there are wires a few centimeters from it that carry 10 to 60A.
Also, the legs are high enough that they can't touch anything on the board.
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DickCappels

Joined Aug 21, 2008
8,710
If it is working now, that’s great. It does not look like an RF inductor. The only problem I see is that the weight of the inductor at the end of those long leads may lead to mechanical damage, such as pulling pads off of the PCB.

I would look for a way of taking stress off the leads and pads.
 

Tonyr1084

Joined Sep 24, 2015
6,887
The only problem I see is that the weight of the inductor at the end of those long leads may lead to mechanical damage, such as pulling pads off of the PCB.
Agree. Use some sort of thin viscosity glue to anchor the coil in place. You may also want to provide some sort of mechanical stress reduction like a stress loop so that with expansion and contraction you don't end up hurting the board.

A secondary concern I have - but it's probably negligible - is the balance of the machine. The physically larger coil being offset so far could cause a control issue where the machine wants to lean to one side and therefore be prone to drifting that way.
 

LowQCab

Joined Nov 6, 2012
2,050
The Tuning of your Accelerometer-Filters will be affected by the increased weight on the Board
and the different vibrations caused by this new weight being mounted to the Board with "springs",

( the long wires will cause the Choke to vibrate at some specific Frequency,
if you're lucky,
the Frequency will be too high to make a noticeable difference in performance ).

The best thing to do is to get a new Flight-Controller, they're cheap,
but first find out were your 5-Volt Regulator is being shorted-out on occasion.
Maybe some Sloppy Soldering that went un-noticed ?
Chokes don't just arbitrarily "burn-up" by chance,
a Short-Circuit caused an over-load at some point.
.
.
.
 

Thread Starter

muslii

Joined May 4, 2022
4
The Tuning of your Accelerometer-Filters will be affected by the increased weight on the Board
and the different vibrations caused by this new weight being mounted to the Board with "springs",

( the long wires will cause the Choke to vibrate at some specific Frequency,
if you're lucky,
the Frequency will be too high to make a noticeable difference in performance ).

The best thing to do is to get a new Flight-Controller, they're cheap,
but first find out were your 5-Volt Regulator is being shorted-out on occasion.
Maybe some Sloppy Soldering that went un-noticed ?
Chokes don't just arbitrarily "burn-up" by chance,
a Short-Circuit caused an over-load at some point.
.
.
.
This happened after a crash, my buzzer was loose and not insulated properly and it got shorted by a part of the frame, so I already dealt with that.
I did a short test flight and it behaved pretty much just as before. I could buy a new board, but if I can get this one to work well then I don't see why.
I could solder wires to it and put it somewhere next to the board so that it does not mess with the sensors.
 

LowQCab

Joined Nov 6, 2012
2,050
Extending wires off the Board, that operate at extremely High-Frequencies,
could cause problems with the stable-operation of the Voltage-Regulator.

"" .......... if I can get this one to work well then I don't see why. ""
I can only assume that You are new to the Hobby, and just "messin'-around",
because no serious Pilot would try to "fix-it".
It will only perform correctly when it's in its standard, factory-supplied, "solid-form".
.
.
.
 

Thread Starter

muslii

Joined May 4, 2022
4
Extending wires off the Board, that operate at extremely High-Frequencies,
could cause problems with the stable-operation of the Voltage-Regulator.

"" .......... if I can get this one to work well then I don't see why. ""
I can only assume that You are new to the Hobby, and just "messin'-around",
because no serious Pilot would try to "fix-it".
It will only perform correctly when it's in its standard, factory-supplied, "solid-form".
.
.
.
I get your point, but what about replacing it with the same SMD one that was there in the first place? I did not do that as I would have to wait 2 months for the part from China, but I am considering it now.
 
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