beyond magic smoke has been escapee

[hussamaldean]

Hi
this is not the magic smoke has escaped, this is the mother of the magic smoke has escaped



your opinion

[jmsc_02]

I would have turned off the device instead of filming it to catch some anonymous attention and also breathe toxic fumes, but we are living in strange times...

[hussamaldean]

I would have turned off the device instead of filming it to catch some anonymous attention and also breathe toxic fumes, but we are living in strange times...

well, I was wearing a mask 😷
don't worry and I love blowing my stuff

[schmitt trigger]

Video link appears to be broken or missing

[hussamaldean]

Video link appears to be broken or missing

https://i.imgur.com/QOBrrCu.mp4

[Cyberdragon]

I'm sorry sir, your board...it just caught fire! There was nothing I could do!

[MrMobodies]

It looks to be working after that component caught fire at the end of the video.

[German_EE]

I hate that smell.

[Red Squirrel]

Maybe this is a feature to keep the board at a specific temp for better calibration. 

[hussamaldean]

I'm sorry sir, your board...it just caught fire! There was nothing I could do!

yup exactly

It looks to be working after that component caught fire at the end of the video.

the IC which burnt was mosfet driver but not sure about the model number
it is smart charger  which shows case buying cheap stuff can be really dangerous 

I hate that smell.

I love ❤️ it

Maybe this is a feature to keep the board at a specific temp for better calibration. 

this is how cheap Chinese manufacturers think

[whershey]

I recently had an case of magic smoke escaping on an industrial motor control PCB. The board is powered with 24 and 48VDC and controls 4 DC motors.
It is somewhat sophisticated having some I/O and CAN interface as well as Hall effect motor feedback. There are other identical PCBs on the same power circuit and CAN bus.
After the smoke came out, I measured the motor resistances and they were all around 1.7 ohms. Thinking that this was a case of infant mortality, we  replaced the PCB.
A few days later the replacement PCB also failed in the same way. I took the PCB out of its mount and as with the 1st, all I could see was black burn marks covering the entire board. There was nothing to pinpoint where the short originated. The power transistors were still covered with their SIL pads. Do you have any ideas on how to diagnose a problem like this? Is it likely that the PCB (the board itself and not the components) was poor quality and caught fire due to the normal operational heat?

[OwO]

Is it likely that the PCB (the board itself and not the components) was poor quality and caught fire due to the normal operational heat?

That is extremely implausible because normal reflow goes close to 300C, which your board should not go anywhere near during operation. My guess is the design stresses some part and exceeds maximum ratings (for example exceeding transient SOA). If you suspect the problem is thermal the least you can do is take thermal images of the board after an hour of operation.

[whershey]

thermal image is a good suggestion. What is "SOA"?

[OwO]

thermal image is a good suggestion. What is "SOA"?

Safe operating area. All power transistors will have a SOA vs pulse width graph in the datasheet that will tell you the combinations of voltage and current that are safe. Be careful though that this is usually specified at very low duty cycles.