LM339 quad op amp IC exploded a hole 0.0

熊鱼~

LM339 quad op amp IC exploded a hole 0.0 [Copy link]

This is a product of our company. There are many such cases returned after sales, and then I was asked to analyze it. I was dumbfounded when I saw it, and it was a pit! Can you experts ask under what circumstances would such a situation occur? PS: This is the circuit board on the motor protector. Could it be related to the impact of the motor starting moment?

wenyangzeng

It must be overpressure.

sacq

LM339, four-way voltage comparator. Check the crime scene (the board in your hand) to see which circuit has a problem, the input or output, or the power supply?

maychang

It is normal to have a pit. The shiny area at the bottom of the pit is the chip, and the rest is the package and leads. The pit is actually the chip overheating and the plastic package cracking.

chunyang

The reasons must be analyzed based on the circuit and specific application.

熊鱼~

sacq posted on 2019-4-13 20:30 LM339, four-way voltage comparator. Check the crime scene (the board in your hand) to see which circuit has a problem, the input or the output, ...

The input power is provided by the induced electromotive force of the coil. Is it because the high current at the moment of motor startup makes the induced electromotive force too large? I see that the electrolytic capacitor here is only 2.2uF. Would it be better to increase the capacitor or add a voltage regulator?