Please ask.
The above circuit CN2 is followed by a load, and the current is about 40mA. PB1 is connected to MCU IO port, R12 is connected to 1K resistor. When doing high temperature test on this circuit at 85℃, transistor Q1 burned out, BE junction burned out, and the load behind did not work. Various calculations should feel no problem, but It's broken, the attachment is the information of the transistor, please let me analyze the reason, thank you.
Keri Posted on January 27, 2021
Your schematic does not show the voltage from c to ground, so there is no way to find the problem.
Monet Posted on January 27, 2021
What is CN2? Relay?
Cate Posted on January 27, 2021
CN2 is a connector, followed by a load module, the load current is about 40mA.
Herman Posted on January 27, 2021
If I am not wrong, did you design this circuit yourself? There is an error in principle, it is not surprising that it burned.
