I had a PICaxe microcontroller on a custom printed circuit board catch fire and fry itself and a nearby board. Have you ever seen this happen ever? It doesn't seem like the kind of failure caused by a gradual overheating with a current overload. It seems more like a large failure caused by a high voltage getting in somehere. Here are some details:
-The board powers a small array of 12v DC LEDs, and a 12v DC linear solenoid. The solenoid is protected with a diode to keep back EMF from getting to the board.
-The board is wired to a 12volt DC power supply. The pic is powered by a voltage regulator and capacitor combination as recommended by the PICaxe manuals.
-This morning, the problem was observed as smoke came from the box containing the boards. None of the electronics worked.
-Upon opening the box, two of the boards were chared, appearently originating from one of the PICs and possibly a large power transistor.
-The boards were working fine for a whole week, running 10 hours per day. Then, this problem suddenly happened. Up untill then, no heat or smoke or anything was observed.
-The burn pattern in the box indicated a rapid flare-up and catastrophic failure in a very short amount of time.
There are other details involved in this that might be the cause, but what I want to know is if this has occured to anyone else.
Have you ever seen a board catch fire from an overheated component on a 12v DC board?
Have you ever burned up a PIC and did it ever get to the point of flames?
Have you ever seen this failure caused by a large voltage accidentally being applied to a PCB? (which is one possible scenario I can imgaine... a high voltage potential leaking across a component, such as the solenoid, and making it to the board)
Just please share your experiences. I'll have the boards in a few days to inspect and take pictures of.
Thanks in advance for any help.
Eddie
-The board powers a small array of 12v DC LEDs, and a 12v DC linear solenoid. The solenoid is protected with a diode to keep back EMF from getting to the board.
-The board is wired to a 12volt DC power supply. The pic is powered by a voltage regulator and capacitor combination as recommended by the PICaxe manuals.
-This morning, the problem was observed as smoke came from the box containing the boards. None of the electronics worked.
-Upon opening the box, two of the boards were chared, appearently originating from one of the PICs and possibly a large power transistor.
-The boards were working fine for a whole week, running 10 hours per day. Then, this problem suddenly happened. Up untill then, no heat or smoke or anything was observed.
-The burn pattern in the box indicated a rapid flare-up and catastrophic failure in a very short amount of time.
There are other details involved in this that might be the cause, but what I want to know is if this has occured to anyone else.
Have you ever seen a board catch fire from an overheated component on a 12v DC board?
Have you ever burned up a PIC and did it ever get to the point of flames?
Have you ever seen this failure caused by a large voltage accidentally being applied to a PCB? (which is one possible scenario I can imgaine... a high voltage potential leaking across a component, such as the solenoid, and making it to the board)
Just please share your experiences. I'll have the boards in a few days to inspect and take pictures of.
Thanks in advance for any help.
Eddie